Palais du Pharo, Marseille 16-18 Nov. 2011

Transcription

Palais du Pharo, Marseille
16-18 Nov. 2011
Organizing Committee
Congress and Scientific Committee President: Renaud MAILLARD
Organizing Committee President: Hervé NAVETAT
General Organization / PCO: Franck LAFARGUE (B-Beyond Network)
Congress General Secretariat: Claire ESPINASSE
Scientific Committee
BARRETT David C. (University of Glasgow Vet School, Scotland)
CANNAS DA SILVA João (Vaqca-International, Portugal)
CHASTANT-MAILLARD Sylvie (ENV Toulouse, France)
DORCHIES Philippe (ENV Toulouse, France)
GELFERT Carl Christian (University of Veterinary Medicine Vienna, Austria)
GENTILE Arcangelo (Università di Bologna, Italy)
KLEE Wolfgang (LMU München, Germany)
NOORDHUIZEN Jos (Vaqca-International, France/Portugal)
ORTEGA MORA Luis Miguel (Universidad Complutense de Madrid, Spain)
SCHELCHER François (ENV Toulouse, France)
STEINER Adrian (University of Bern, Switzerland)
VALARCHER Jean François (Statens Veterinärmedicinska Anstalt / Swedish University of
Agricultural Sciences, Uppsala, Sweden)
Editors
R. MAILLARD & H. NAVETAT
Société Française de Buiatrie
Siège social : ENVT F-31076 Toulouse - Secrétariat : 240 ch. du Clos de Jeanou – F-82370 Labastide St Pierre
Tel (33) 9 62 09 67 43 – [email protected] - www.buiatricsforum.com
©Société Française de Buiatrie 2011 - ISBN 2-903623439
TOUS DROITS DE REPRODUCTION, D’ADAPTATION ET DE TRADUCTION RESERVES POUR TOUS PAYS
MISE EN PAGE ET COUVERTURE :
Claire Espinasse
EBF 2011 – Marseille, 16-18 Nov. 2011 – p. 1
TABLE OF CONTENTS
KKeeyynnootteess aanndd oorraall ccoom
mm
muunniiccaattiioonnss
Neospora and toxoplasma ................................................................................................................................................................................... 7
Results of a French multicentric epidemiological survey on coccidiosis and worms in dairy and beef calves....................................................... 17
Evaluation of botanic active compounds on the coccidian excretion and the growth performance of dairy calves............................................... 19
Additional feeding of herbs in lambs: influence on shedding of Eimeria spp. and on weight gain........................................................................ 21
Dictyocaulus viviparus: a field study of parasite dynamics in regularly infested herds......................................................................................... 23
New data on kinetics of infection by Besnoitiosis in cattle herds from endemic and non-endemic french areas.................................................. 25
Speaking about genital inflammation rather than uterine infection ..................................................................................................................... 27
Establishment of a standard operating procedure for prediction of the time of calving in cattle ......................................................................... 33
Pregnancy-associated glycoprotein ELISA as sensitive and specific laboratory based pregnancy test in cattle................................................... 35
Managing heat stress in dairy cattle: occurrence & control ................................................................................................................................ 37
Identification of the transmission model of S. uberis in a dairy herd: are dynamic measurement and genotyping useful techniques?................. 39
Current concepts and future developments in surgery, anaesthesia and pain management ............................................................................... 41
Evaluation of three different methods for anaesthesia of calves in umbilical surgery.......................................................................................... 45
Blood composition parameters in calf from birth to 60 days .............................................................................................................................. 47
Surgical treatment of severe udder infection by vascular ligature in cow............................................................................................................ 49
Long term epidemiologic survey of sensitivity to antimicrobials of pathogens involved in mastitis, respiratory or digestive disorders ................ 51
Is Mannheimia haemolytica highly contagious among newly-received bulls at fattening operations? .................................................................. 53
Forced oscillation technique measurements of pulmonary function: an objective tool to assess the respiratory function in cattle ...................... 55
The prevalence of rib fractures and association with lameness in 13 dairy herds............................................................................................... 57
Recent epidemiological insights on control of Q fever and paratuberculosis....................................................................................................... 59
BTV and EHDV epidemiological situation in the French Martinique and la Réunion Island .................................................................................. 61
BRSV-ISCOMs induce clinical and virological protection in young calves with maternal antibodies ...................................................................... 63
Outbreaks of jaundice in young calves - a novel disease?.................................................................................................................................. 65
Assessment of the curative and preventive effectiveness of different practical modalities of collective treatment of digital dermatitis ................ 67
Dairy calf mortality in France in 2005 and 2006................................................................................................................................................ 69
Lung auscultation recordings and sonographic images from normal cattle and those with respiratory tract pathology ...................................... 71
BRSV- infections in Norwegian dairy cattle......................................................................................................................................................... 73
Genetic loci associated with digital dermatitis in UK Holsteins ............................................................................................................................ 75
Sub-acute ruminal acidosis: what to do ‘in the field’ .......................................................................................................................................... 77
Effect of dietary potassium content and anionic salts on the mineral balance in periparturient dairy cows ......................................................... 83
Long-term measurement of rumen pH in dairy cows by an indwelling and wireless data transmitting unit.......................................................... 85
Herd audit for bovine parasitology: an effective tool to customize anthelmintic treatments to the real risk......................................................... 87
Neonatal diarrhea: calves from vaccinated flocks against rotavirus, coronavirus and E. coli excrete less of Cryptosporidium parvum................. 89
Emerging resistance to carbapenems in Gram negatives recovered from dairy cows ......................................................................................... 91
News about mastitis-causing staphylococci........................................................................................................................................................ 93
Practical application of a tool to evaluate mastitis risk factors and costs in 25 Italian dairy herds.................................................................... 105
Relationship between teat end shape and callosity ring and mastitis bacteria isolated in quarters of Norwegian Red cows .............................. 107
Acute Mastitis with SIRS: the impact of different treatment regimes on acute phase proteins and milk quality .................................................. 109
Follow-up study of the use and the effects of a vaccine against staphylococcal and coliform mastitis (Startvac®, Hipra) in French dairy farms 111
Detection of Staphylococcus aureus Genotype B in samples of routine milk recording and bulk tank milk with PCR .......................................... 113
Analysing dairy health through farmer’s competencies and advice makers: examples of dairy cow mortality and udder health ........................ 115
FFrreenncchh BBuuiiaattrriiccss AAssssoocciiaattiioonn SSyym
mppoossiiuum
m
PPoosstteerrss
Keynotes and oral communications
Neosporosis and toxoplasmosis in farmed livestock: options for control
L. INNES - The Moredun Group, Penicuik, Midlothian, Scotland
[email protected]
Introduction
Neospora caninum and Toxoplasma gondii are two of the most important causes of infectious abortion in livestock
worldwide. Both are protozoan parasites and are genetically very closely related although there are distinct differences
in their biology and respective host-pathogen relationship. The definitive host for Neospora caninum is the dog and
clinical disease manifests mainly in cattle and dogs. There is no convincing evidence to date that Neospora is a zoonotic
pathogen. Cats and members of the cat family are the definitive hosts for T. gondii and all warm blooded animals
including humans can be infected with the parasite with a wide range of disease consequences across different animal
species.
This paper will review the current challenges involved in devising strategies to help prevent and control neosporosis and
toxoplasmosis in farmed livestock.
Bovine neosporosis: background and context
Bovine neosporosis is an important cause of reproductive failure in both dairy and beef cattle worldwide. The disease
may be transmitted to cattle through consumption of infective oocysts present in contaminated feed and/or water or via
vertical transmission from dam to calf in utero (Dubey et al., 2007). Clinical disease is seen in the developing fetus
where common signs include, abortion, mummification and re-absorbtion following foetal death. Where infection of the
foetus occurs later in gestation, during the final trimester, the calf is likely to be born congenitally infected and may
show neurological signs at birth or appear clinically normal (Buxton et al., 2002). Factors that are likely to affect
disease severity and outcome include: the timing and duration of parasitaemia in the pregnant dam, where several
studies have shown that the earlier in gestation that infection of the placenta and hence the foetus occurs the more
severe the consequences; the dynamics of the maternal immune response in the pregnant dam and the relative maturity
of the foetal immune responses. These factors have been studied using controlled experimental infections of pregnant
cattle and have provided important insights into the pathogenesis of bovine neosporosis and how cattle may resist
disease (Innes et al., 2005). With new tools available to distinguish parasite isolates and strains it may now be possible
to determine whether there may be differences in virulence and cross protection between different Neospora isolates
(Regidor-Cerrillo et al., 2006, 2008).
Understanding the relative risk posed: following a primary infection prior to or during pregnancy; following a
recrudescence of a previous infection; comparing congenitally infected versus exogenously infected animals and the
likelihood of repeated abortions occurring in the same animal are highly desirable in determining the most effective
control strategies to apply against bovine neosporosis.
Reports from the literature emphasise the high rate of vertical transmission associated with N. caninum infection which
can occur over several generations and in successive pregnancies (Dubey et al., 2006). The relative likelihood of
N. caninum infected animals to abort is a subject of great debate and of significant relevance. N. caninum infected
animals are 3- 7 times more likely to abort than un-infected animals with congenitally infected heifers in their first
pregnancy thought to be particularly at risk (Pare et al., 1997). A study conducted in the USA followed a group of
congenitally infected heifer calves through pregnancy and showed that this group had a 7.4 fold higher risk of aborting
during their first pregnancy compared to an uninfected control group (Thurmond & Hietala, 1997a).
Studies looking at the rates of congenital transmission over consecutive pregnancies have shown a decreased rate of
transmission over time (Romero et al., 2003; Dijkstra et al., 2003) suggesting that dams develop some immunity to help
reduce vertical transmission of the parasite. There are also reports that neosporosis may cause repeat abortions in cattle
although the reported rates vary from <5% (Anderson et al., 1995) to 51% (Pabon et al., 2007). These variations
reported in the literature make it difficult to draw definitive conclusions concerning the disease risk posed by N.
caninum infected animals and the conditions leading to the development of protective immunity against disease.
The complex host-pathogen interaction with bovine neosporosis suggests the value of taking into consideration whether
the original infection in cattle occurred in-utero or post-natally as this may have a profound effect on the priming of the
immune system in particular to the endogenous infection (Innes & Vermeulen, 2006; Innes et al., 2007).
Epidemiological studies following disease outbreaks (ie predominantly exogenous infection sources) may provide
important clues about disease risk and the ability of cattle to develop effective immunity against the parasite following
post natal acquisition of infection. A recent longitudinal study conducted in the Netherlands followed a dairy herd that
had experienced a point source outbreak of infection (Dijkstra et al., 2008). Most post-natally infected dams remained
sero-positive over the three year study and 58% of the offspring from these dams were found to be sero-positive
indicating that vertical transmission of the endogenous infection had occurred (Dijkstra et al., 2008) although the
percentage of animals affected was lower than other published studies, >90% (Davison et al., 1999) in which the seropositive cohort group was not grouped into congenitally infected or post-natally infected animals. A further serological
study in New Zealand using dam-daughter pairs from a herd that had experienced a Neospora outbreak showed that
12.5% of the offspring were sero-positive (Schares et al., 1999) showing that the risk of vertical transmission occurring
may be related to whether the dam was infected congenitally or post-natally.
Another factor that is likely to affect disease risk and pathogenesis is genetic and biological variation between different
Neospora isolates. Molecular tools are being developed to distinguish isolates (Regidor-Cerrillo et al., 2006) which will
be very valuable tools for epidemiological studies. There is very little work published comparing differences in
virulence and pathogenicity between isolates although differences have been shown using mouse models of infection
(Atkinson et al., 1999; Schock et al., 2001, Regidor-Cerrillo et al., 2008)
Production losses associated with neosporosis
Economic losses associated with bovine neosporosis include reproductive failure and replacement costs associated with
culling of infected stock (Dubey et al., 2007). There are also indirect costs associated with diagnostic investigations and
re-breeding. Some studies report loss of milk yields associated with Neospora prevalence within herds (Thurmond and
Hietala, 1997b; Hernandez et al., 2001)), whereas other studies report little effect on milk yields (VanLeeuwen et al.,
2002). In devising a control strategy for bovine neosporosis it is important to understand as much as possible about the
epidemiology of disease which will vary between, countries, regions and even on different farms. A cost-benefit
analysis of different strategies should be undertaken to look at the costs involved in applying diagnostic, biosecurity and
preventative methods compared with the benefit of reducing production losses associated with disease. This analysis
should take into account the herd sero-prevalence, the likely risk of abortions, the cost of replacement animals and the
milk and meat prices the farmer might expect at current market rates (Reichel & Ellis, 2006; 2008). If the epidemiology
results suggest that the in-herd prevalence is low, farmers may be advised to apply a test and cull approach (Hall et al.,
2005) or simply do nothing (Reichel & Ellis, 2006). However these approaches may not be cost-effective in herds with
a high prevalence of Neospora.
The majority of work on the epidemiology of bovine neosporosis has taken place in dairy herds and less is known about
the economic consequences of neosporosis in beef herds. A study of eight beef herds in Canada showed a higher cull
rate in Neospora sero-positive animals (Waldner et al., 1998) and a further study reported an association between seropositivity and reduced weight in beef calves (Barling et al., 2000).
Control options
Accurate diagnosis of Neospora infection is an important tool in understanding the extent of the problem in the field
and in devising effective control strategies against the disease. Application of histopathology and immunocytochemistry techniques along with molecular tools are useful to detect lesions and evidence of the parasite in aborted
foetal tissues, which will aid diagnosis and provide molecular information on parasite strains and source tracking.
Various methods exist to detect quantity, specificity and avidity of Neospora-specific antibodies in either serum or milk
samples from affected herds. These techniques can be useful to look at herd sero-prevalence, testing of replacement and
breeding stock and for use in a test and cull control policy. However, serological tests may be difficult to interpret as
there are reports in the literature of Neospora infected cattle showing fluctuating titres of specific antibodies which may
result in a sero-negative result depending on the cut-off value of the test being used (Conrad et al., 1993; QuintanillaGozalo et al., 2000).
There is a real need for standardized diagnostics to be applied in national or regional reference laboratories to help with
setting up and evaluating control programmes for bovine neosporosis. A recent initiative in Europe produced a book on
Guidelines for diagnosis and control of protozoal abortion in farm ruminants (Ortega-Mora et al., 2007).
Test and cull
As Neospora infected cattle are thought to be an important reservoir of infection and the rates of vertical transmission
within herds are significant, a test and cull approach may be adopted. This approach is dependant on the numbers of
animals affected within the herd and whether the infection pattern in the herd is predominantly as a result of
endogenous transmission, as this approach may not always be the most feasible economic solution. Approaches used
are to test and cull sero-positive/aborting dams (Hall et al., 2005); test and inseminate sero-positive dams with beef bull
semen (Lopez-Gatius et al., 2005) test and exclude sero-positive dams from breeding.
While this approach may prove beneficial in certain situations there is always a danger that naïve animals may pick up
infection from consumption of oocysts, shed by infected dogs, in the environment. Point source outbreaks of infection
are usually associated with a group of naïve animals becoming infected by consuming feed or water contaminated with
environmentally resistant infectious oocysts as these animals have no immunity to N. caninum through prior exposure to
the parasite (Dubey et al., 2006.
Biosecurity
Along with quarantine and testing replacement cattle coming onto the farm, biosecurity measures should also include
prevention of dogs coming in contact with feed and water sources for cattle. In addition, dogs should be prevented from
eating aborted foetuses, placental material or other tissues of potentially infected cattle to reduce the chances of dogs
becoming infected and then shedding N. caninum oocysts in their faeces, contaminating the farm environment. Regular
rodent control should be applied to minimize the potential of rodents acting as intermediate hosts of the parasite.
Embryo transfer
This technique may be useful with high value sero-positive breeding cattle as transfer of embryos from such cattle to
uninfected recipient cattle will result in the offspring being born clear of the infection as endogenous transmission in
utero has been prevented (Baillargeon et al., 2001; Landmann et al., 2002).
Therapeutics
There are currently no therapeutics available that will cure cattle infected with N. caninum and there are concerns about
using therapeutic agents in food animals due to the risk associated with residues being present in meat or milk products
in treated animals. Promising data has been reported using toltrazil to reduce the impact of N. caninum infection in
calves (Kritzner et al., 2002). Effective therapeutics may be useful in association with information concerning the hostpathogen relationship in pregnant cattle to help minimize the consequences of N. caninum infection.
Vaccination
There is much interest in the prospect of developing an effective vaccine against Neospora caninum in cattle and a
realistic target would be to prevent abortion/disease (Innes et al., 2002; Innes and Vermeulen, 2006). As discussed
above, development of protective immunity may be significantly affected by whether cattle first encounter the parasite
in utero when their immune systems are still developing or whether they encounter the parasite post-natally (Innes et
al., 2002). It has been postulated that cattle may develop some form of immuno-tolerance to the endogenous infection
they acquired in utero and that this may compromise their ability to respond effectively to this endogenous infection
later in life. Studies have shown that it is possible to induce protective immunity in cattle by immunizing naïve animals
prior to mating with live parasite preparations (Innes et al., 2001; Williams et al., 2007) showing that it is possible to
induce protective immunity in cattle to protect against abortion and exogenous vertical transmission. Live vaccine
preparations are more likely to be successful than killed approaches as N. caninum is an obligate intracellular parasite
and cell-mediated immune mechanisms are thought to be critical components of a protective immune response (Innes
and Vermeulen, 2006). Live vaccines are more likely to result in effective processing and presentation of Neospora
antigens in the appropriate MHC background to enable induction of T-cell immune responses (Innes et al., 2011).
Various killed vaccine approaches have been tested in cattle with limited efficacy reported (Andrianarivo et al., 2000;
Williams et al., 2007). The only commercial vaccine available to protect against disease comprises killed Neospora
tachyzoites formulated with an adjuvant (Havlogen). Bovilis Neoguard.™ The vaccine is available in USA, New
Zealand and some other countries worldwide and there have been mixed reports as to its ability to protect against
disease in the field (Schetters et al., 2004).
Clearly the development of an effective vaccine would be highly desirable with prevention of disease as a realistic
target. Current evidence would suggest that the vaccine would be most effective if administered to naïve cattle prior to
mating and a live vaccine is likely to be more effective in inducing protective T-cell-mediated immune responses.
Vaccination is unlikely to be effective against an endogenous infection acquired in-utero due to issues associated with
ontogeny and priming of the immune response.
Ideally, a candidate vaccine should induce effective and long lived protective immunity; be safe to use; be cost effective
to produce and should contain a marker to allow discrimination between vaccinated and naturally infected animals
(DIVA vaccine).
Ovine toxoplasmosis: background and context
The protozoan parasite Toxoplasma gondii (T. gondii) is one of the most successful parasites worldwide and is able to
infect all warm blooded animals including people. There is a wide spectrum of disease associated with T. gondii
infection which is dependant on: the host species; the immune status of the host and the virulence of the particular strain
of Toxoplasma (Innes, 2010).
T. gondii is a major cause of infectious abortion in sheep in many temperate areas of the world which have favourable
climatic conditions to allow sporulation and long term survival of T. gondii oocysts in the environment (Innes et al.,
2009a). Cats and members of the cat family are definitive hosts of the parasite and following a primary infection, the
parasite undergoes sexual development in the gut of the cat resulting in the production of oocysts which are shed in
large numbers in the faeces (Dubey & Beattie, 1988). The oocysts are not infective when they are shed and sporulation
takes place in the environment a few days after shedding resulting in the oocysts being infective for intermediate hosts
such as grazing animals. An infected cat may shed millions of oocysts into the environment and it only requires 20
oocysts to cause infection and disease in naïve sheep (McColgan et al., 1988).
Several studies have emphasized the importance of oocysts as the major source of infection for sheep (reviewed by
Innes et al., 2009a). Sero-prevalence studies have shown an increased prevalence with age suggesting that most
infections in sheep occur following exposure to the parasite after birth and that there is a widespread environmental
contamination with T. gondii oocysts (Dabritz et al., 2007).
The disease in sheep mainly occurs following a primary infection in a pregnant ewe which can result in abortion, a
mummified foetus, still birth or birth of a weak congenitally infected lamb (Buxton, 1990). A significant factor in
determining disease severity is the stage of gestation when the ewe becomes infected, the earlier in gestation the more
severe the consequences for the developing foetus (Buxton and Rodger, 2008). Unlike the situation with N. caninum,
following an abortion due to T. gondii, sheep develop good immunity to protect against disease in a subsequent
pregnancy (Innes and Vermeulen, 2006). The protective immune response induced following a primary infection in
sheep involves induction of CD4+, CD8+ and interferon gamma (IFN!), (Innes & Wastling, 1995). These results
suggested that vaccination would be a feasible approach to control toxoplasmosis in sheep.
Unlike neosporosis, toxoplasmosis is a zoonotic disease and infection in people may result in severe disease in the
developing foetus and in immuno-compromised individuals. There are also increasing reports of eye disease in
immuno-competent individuals following infection with T. gondii (Glasner et al., 1992).
Infection may be transmitted to people through the consumption of oocysts contaminating food or water or though
eating undercooked meat containing tissue cysts of T. gondii (Tenter et al., 2000). Therefore there is also a need to look
at control of disease and persistent infection in food animals to help protect public health (Innes, 2010).
Economic impact and disease losses
Although the incidence of ovine toxoplasmosis will vary between countries and regions, a conservative estimate by
Blewett & Trees (1987) suggested losses of around 0.5 million lambs annually in the UK and this would extrapolate to
1.5 million lambs lost in Europe based on current flock numbers.
The incidence of congenitally infected children also varies when comparing reported rates from different countries in
Europe. In UK Toxoplasmosis is estimated to occur in 1:1000/10 000 births. Congenitally infected children may present
with neurological, visual and auditory disorders which require full time care for life. Applying methods to estimate
disease impact such as Disability Adjusted Life Years (DALYS) has shown toxoplasmosis to be one of the most
significant food borne pathogens across the world (Kortbeek et al., 2009).
Control options
As T. gondii oocysts are so widespread in the environment and the minimum infectious dose for sheep is relatively
small it would be difficult to control exposure of grazing animals to oocysts. However, it is sensible to restrict access of
cats to feedbins to help prevent contamination with infected cat faecal material which could be very efficiently spread
around the sheep flock through distribution of feed (Buxton & Rodger, 2008). Education programmes to encourage
people, in particular vulnerable risk groups, to wash vegetables thoroughly, wear gloves when gardening, cook meat
thoroughly and to wash hands prior to food preparation and consumption are used to help prevent transmission of T.
gondii to people (Innes, 2010). Serological screening is used in some European countries eg: France to help manage the
disease in pregnant women (Tenter et al., 2000), although the use of serological screening has not been widely adopted
elsewhere due largely to concerns about treatment options available to patients. Serology based tests can be useful aids
to diagnosis in sheep flocks and to provide epidemiological information (Katzer et al., In Press).
Therapeutics
The mainstay of treatments used to limit acute infection with the tachyzoite stage of T. gondii include, sulphadiazine,
pyrimethamine and spiramycine. The search for new therapeutics has looked at identifying biochemical differences
between parasites and hosts (Coombs and Muller, 2002). There are still no treatments available that will act against the
cyst stage of T. gondii and that will cure animals or people persistently infected with the parasite.
The effects of monensin and decoquinate were tested in pregnant sheep experimentally challenged with T. gondii
oocysts. Both compounds were found to reduce the risk of toxoplasmosis in pregnant ewes (Buxton et al., 1988, 1996).
Similar to the situation with bovine neosporosis there is concern about drug residues in food animals so any treatment of
livestock would have to take withdrawal times into consideration.
Vaccination
As sheep develop protective immunity against further disease, following a primary infection with T. gondii, the prospect
for disease prevention through vaccination is a realistic prospect (Innes et al., 2009a). Current knowledge of protective
immune responses in sheep to T. gondii and the fact that the parasite multiplies within host cells suggests that a live
vaccination approach is likely to be more successful that a killed vaccine (Innes et al., 2011).
The only commercial vaccine available to protect sheep against congenital toxoplasmosis (Ovilis Toxovax™)
comprises a live incomplete strain of T. gondii (Innes & Vermeulen, 2006). The S48 strain of T. gondii was originally
isolated from a case of ovine toxoplasmosis in New Zealand, where it was maintained in the laboratory by continuous
passage for many years. Over time researchers noticed that the strain had lost the ability to differentiate into bradyzoites
or oocysts and it would only undergo limited multiplication in vivo making it an attractive live vaccine candidate
(Wilkins et al., 1988). The vaccine, which is administered prior to mating will successfully protect ewes against
congenital toxoplasmosis (O’Connell et al., 1988) and this protection will last for at least 18 months in the absence of
further external challenge (Buxton et al., 1993).
As undercooked meat from T. gondii infected food animals may be an important source of infection for people (Tenter
et al., 2000, Cook et al., 2000, Dubey et al., 2005), vaccines to protect against T. gondii cyst development would be
desirable. In experiments looking at this, live vaccines have proved to be more efficacious than killed preparations
(Innes et al., 2009b), with most work in this area focusing on reducing T. gondii cyst development in pigs (Garcia et al.,
2005; Jongert et al., 2008).
There is also interest in developing a vaccine in cats to reduce/prevent oocyst shedding and thus reduce a major source
of infection for intermediate hosts and minimize contamination of the environment. The most effective vaccine
candidate is a live mutant strain of T. gondii T263 which will only undergo partial development in the gut of the cat and
induce protective immunity preventing oocyst shedding (Frenkel et al., 1991). A field trial to test this vaccine found that
it reduced shedding of oocysts in cats and as a result also protected intermediate hosts in the vicinity from become
infected through consumption of oocysts in the environment (Mateus-Pinilla et al., 1999, 2002).
Considerable success has been achieved in developing vaccines to protect against T. gondii infections using live vaccine
approaches compared to killed preparations (Innes et al., 2011). Although live vaccines are effective in inducing
protective immunity they do have drawbacks of safety issues, short shelf life and storage and delivery limitations.
However, live vaccines do have a major advantage over their killed counterparts as they do induce highly effective
protective immunity.
Concluding remarks
Neosporosis and Toxoplasmosis are important causes of reproductive failure in farm livestock resulting in significant
economic losses to producers. Advances in research have improved our understanding of the epidemiology,
transmission routes and the often complex host-pathogen interaction in the ruminant intermediate host. This knowledge
is being applied to improve diagnostic capability and application, the strategic use of therapeutics to minimize disease
severity and the design and production of effective vaccines to prevent disease. Vaccination is an attractive control
option as it works by preventing disease through stimulating the host’s own immune defences, thus providing a
sustainable control option, improving production efficiency and reducing waste. Food security is one of the major
global challenges we face going forward and work to reduce the impact of disease in livestock will be vital to improve
production efficiency and reduce waste.
Acknowledgements
The author would like to acknowledge the support of the Scottish Government and the Creative Science Company.
References
Anderson et al. - Evaluation of abortions in cattle attributable to neosporosis in selected dairy herds in California.
JAVMA, 1995, 207:1206-1210.
Andrianarivo AG et al. - A POLYGEN-adjuvanted killed Neospora caninum tachyzoite preparation failed to prevent
foetal infection in pregnant cattle following i.v/i.m. experimental tachyzoite challenge. Int J Parasitol, 2000, 30:985990.
Atkinson R et al. - Comparison of the biological characteristics of two isolates of Neospora caninum. Parasitol, 1999,
118:363-370.
Baillargeon P et al. - Evaluation of the embryo transfer procedure proposed by the International Embryo Transfer
Society as a method of controlling vertical transmission of Neospora caninum in cattle. JAVMA, 2001, 218:1803-1806.
Barling KS et al. - Association of serological status for Neospora caninum with post weaning weight gain and carcass
measurements in beef calves. JAVMA, 2000, 217:1356-1360.
Blewett DA & Trees AJ - The epidemiology of ovine toxoplasmosis with special respect to control. Br Vet J, 1987,
143:128-135.
Buxton D - Ovine toxoplasmosis: a review. J Roy Soc Med, 1990, 83:509-511.
Buxton D et al. - Further studies in the use of monensin in the control of ovine toxoplasmosis. J Comp Pathol, 1988,
98:225-236.
Buxton D et al. - Decoquinate and the control of experimental ovine toxoplasmosis. Vet Rec, 1996, 138:434-436.
Buxton D, McAllister MM, Dubey JP - The comparative pathogenesis of neosporosis. Trends Parasitol, 2002, 18:546552.
Buxton D, Rodger SM - Toxoplasmosis and neosporosis. In Diseases of Sheep. 4th Ed (ed Aitken, I.D.) WileyBlackwell, Hoboken. 2008:112-118.
Buxton D et al. - Experimental challenge of sheep 18 months after vaccination with a live (S48) Toxoplasma gondii
vaccine. Vet Rec, 1993, 133:310-312.
Conrad PA et al. - Detection of serum antibody responses in cattle with natural or experimental Neospora infections. J
Vet Diag Invest, 1993, 5:572-578.
Cook AJ et al. - Sources of of toxoplasma infection in pregnant women: European multi centre case-control study,
European Research Network on Congenital Toxoplasmosis. BMJ, 2000, 15:142-147.
Coombs GH & Muller S - Recent advances in the search for new anti-coccidial drugs. Int J Parasitol, 2002, 32:497-508.
Dabritz HA et al. - Detection of Toxoplasma gondii like oocysts in cat faeces and estimates of the environmental oocyst
burden. JAVMA, 2007, 231:1676-1684.
Davison HC, Otter A, Trees AJ - Estimation of vertical and horizontal transmission parameters of Neospora caninum
infections in dairy cattle. Int J Parasitol, 1999, 29:1683-1689.
Dijkstra T et al. - Evaluation of a single serological screening of dairy herds for Neospora caninum antibodies. Vet
Parasitol, 2003, 110:161-169.
Dijkstra T et al. - Natural postnatal Neospora caninum infection in cattle can persist and lead to endogenous
transplacental transmission. Vet Parasitol, 2008, 152:220-225.
Dubey JP & Beattie CP - Toxoplasmosis of Animals and Man. Boca Raton, Florida: CRC Press, 1988.
Dubey JP, Buxton D, Wouda W - Pathogenesis of Bovine Neosporosis. J Comp Path, 2006, 134:267-289.
Dubey JP et al. - Prevalence of viable Toxoplasma gondii in beef, chicken, and pork from retail meat stores in the
United States: Risk assessment to consumers. J Parasitol, 2005, 91:1082-1093.
Dubey JP, Schares G, Ortega-Mora LM - Epidemiology and Control of Neosporosis and Neospora caninum. Clin Micro
Rev, 2007, 20:323-367.
Frenkel JK et al. - Prospective vaccine prepared from a new mutant of Toxoplasma gondii for use in cats. Am J Vet Res,
1991, 52:759-763.
Garcia JL et al. - Partial Protection against tissue cyst formation in pigs vaccinated with crude rhoptery proteins of
Toxoplasma gondii. Vet Parasitol, 2005, 129:209-217.
Glasner PD et al. - An unusually high seroprevalence of ocular toxoplasmosis in southern Brazil. Am J Opthamol, 1992,
114:136-144.
Hall CA, Reichel MP, Elllis JT - Neospora abortions in dairy cattle: diagnosis, mode of transmission and control. Vet
Parasitol, 2005, 128:231-241.
Hernandez J, Risco C, Donovan A - Risk of abortion associated with Neospora caninum and milk production in dairy
cows. JAVMA, 2002, 219:632-635.
Innes EA - Vaccination against Toxoplasma gondii: an increasing priority for collaborative research? Expert Rev
Vaccines, 2010, 9:1117-1119.
Innes EA et al. - Immune responses to Neospora caninum and prospects for vaccination. Trends Parasitol, 2002,
18:497-504.
Innes EA et al. - Ovine toxoplasmosis. Parasitol, 2009a, 136:1887-1894.
Innes EA et al. - Veterinary vaccines against Toxoplasma gondii. Mem Inst Oswaldo Cruz, 2009b, 104:246-251.
Innes EA et al. - Comparative host-parasite relationship s in ovine toxoplasmosis and bovine neosporosis and strategies
for vaccination. Vaccine, 2007, 25:5495-5503.
Innes EA et al. - Developing vaccines to control protozoan parasites in ruminants: Dead or alive? Vet Parasitol, 2011,
180:155-163.
Innes EA, Vermeulen AN - Vaccination as a control strategy against the coccidial parasites Eimeria, Toxoplasma and
Neospora. Parasitol, 2006, 133:145-168.
Innes EA, Wastling JM - Analysis of in vivo immune responses during Toxoplasma gondii infection using the technique
of lymphatic cannulation. Parasitol Today, 1995, 11:268-271.
Innes EA et al. - The host-parasite relationship in bovine neosporosis. Vet Imm Immunopathol, 2005, 108:29-36.
Innes EA et al. - Protection against vertical transmission in bovine neosporosis. Int J Parasitol, 2001, 31:1523-1534.
Jongert E et al. - An enhanced GRA1-GRA7 cocktail DNA vaccine primes anti-Toxoplasma immune responses in pigs.
Vaccine, 2008, 26:1025-1031.
Katzer F et al. - Toxoplasma gondii seroprevalence in 125 sheep flocks in Scotland: Increased positivity relative to age.
Vet Res (2011, in Press)
Kortbeek LM et al. - Congenital toxoplasmosis and DALYs in the Netherlands. Mem Inst Oswaldo Cruz, 2009,
104:370-373.
Kritzner S et al. - An explorative study to assess the efficacy of toltrazuril-sulfone (Ponazuril) in calves experimentally
infected with Neospora caninum. Ann Clin Microbiol, 2002, 1:1-4
Landmann JK et al. - Confirmation of the prevention of vertical transmission of Neospora caninum in cattle by the use
of embryo transfer. Aust Vet J, 2002, 80:502-503.
Lopez-Gatius F et al. - The use of beef bull semen reduced the risk of abortion in Neospora seropositive dairy cows. J
Vet Med, 2005, 52:88-92.
Mateus-Pinilla NE et al. - A field trial of the effectiveness of a feline Toxoplasma gondii vaccine in reducing T. gondii
exposure for swine. J Parasitol, 1999, 85:855-860.
Mateus-Pinilla NE, Hannon B, Weigel RM - A computer simulation of the prevention of the transmission of
Toxoplasma gondii on swine farms using a feline T. gondii vaccine. Prev Vet Med, 2002, 55:17-36.
McColgan C, Buxton D, Blewett D - Titration of Toxoplasma gondii oocysts in non-pregnant sheep and the effects of
subsequent challenge during pregnancy. Vet Rec, 1988, 123:467-470.
O’Connell E, Wilkins MF, Te Punga WA - Toxoplasmosis in sheep. II. The ability of a live vaccine to prevent lamb
losses after an intravenous challenge with Toxoplasma gondii. NZ Vet, 188, J. 36:1-4.
Ortega-Mora LM et al. - Protozoal abortion in farm ruminants. Guidelinesfor diagnosis and control. CAB International,
Oxfordshire, UK, 2007.
Pabon M et al. - Chronic Neospora caninum infection and repeat abortion in dairy cows: A three year study. Vet
Parasitol, 2007, 147:40-46.
Pare J, Thurmond MC, Hietala SK - Neospora caninum antibodies in cows during pregnancy as a predictor of
congenital infection and abortion. J Parasitol, 1997, 83:82-87.
Quintanilla-Gozalo A et al. - Observational studies in Neospora caninum infected dairy cattle: relationship infectionabortion and gestational antibody fluctuations. Int J Parasitol, 2000, 30:900-906.
Regidor-Cerillo J et al. - Multilocus microsatellite analysis reveals extensive genetic diversity in Neospora caninum . J
Parasitol, 2006, 92:517-524.
Regidor-Cerrillo J et al. - Isolation and genetic characterization of Neospora caninum from asymptomatic calves in
Spain. Parasitol, 2008, 135:1651-1659.
Reichel MP, Ellis JT - If control of Neospora caninum infection is technically feasible does it make economic sense?
Vet Parasitol, 2006, 142:23-34.
Reichel MP, Ellis JT - Re-evaluating the economics of neosporosis control. Vet Parasitol, 2008, 156:361-362.
Romero JJ, Frankena K - The effect of the dam-calf relationship on serostatus to Neospora caninum on 20 Costa Rican
dairy farms. Vet Parasitol, 2003, 114:159-171.
Schares G, Conraths FJ, Reichel MP - Bovine neosporosis: comparison of serological methods using outbreak sera from
a dairy herd in New Zealand. Int J Parasitol, 1999, 29:1659-1667.
Schetters T et al. - Intervet Symposium: Bovine Neosporosis. Vet Parasitol, 2004, 125:137-146.
Schock A et al. - Genetic and biological diversity among isolates of Neospora caninum. Parasitol, 2001, 123:13-23.
Tenter AM, Heckeroth AR, Weiss LM - Toxoplasma gondii: from animals to humans. Int J Parasitol, 2000, 30:12171258.
Thurmond MC, Hietala SC - Effect of congenitally acquired Neospora caninum infections on risk of abortion and
subsequent abortions in dairy cattle. Am J Vet Res, 1997a, 58:1381-1385.
Thurmond MC, Hietala SC - Effect of Neospora caninum infection on milk production in first lactation dairy cows.
JAVMA, 1997b, 210:672-674.
VanLeewen JA, Keefe GP, Tiwari A - Seroprevalence and productivity effects on infection with bovine leukemia virus,
Mycobacterium avium subspecies paratuberculosis and Neospora caninum in maritime Canadian dairy cattle. Bov
Pract, 2002, 36:86-91.
Waldner CL, Janzen ED, Ribble CS - Determination of the association between Neospora caninum infection and
reproductive performance in beef herds. JAVMA, 1998, 213:685-690.
Wilkins MF, O’Connell E, Te Punga WA - Toxoplasmosis in sheep III. Further evaluation of the ability of a live
Toxoplasma gondii vaccine to prevent lamb losses and reduce congenital infection following experimental oral
challenge. NZ Vet J, 1988, 36:86-89.
Williams DJ et al. - Immunisation of cattle with live tachyzoites of Neospora caninum confers protection against fetal
death. Infect Immun, 2007, 75:1343-1348.
Results of a French multicentric epidemiological survey on coccidiosis
and worms in dairy and beef calves
J.P. ALZIEU - Laboratoire Départemental Ariège, Foix, France
[email protected]
M. BOUTET, W. PETERS - Janssen SA, Issy les Moulineaux, France
P. DORCHIES - ENV Toulouse, France
Protocol
Individual faecal samples of groups of 5 calves, similarly aged, are sampled twice a week, from 2 weeks of age, with a
timing depending of the type of livestock. So 12 individual faecal samples are collected for each calf until 6th or 7th
week of age. Counting and identification of worms and coccidian species by coprologic examination are registered. The
identification, on pooled samples (5 calves together), of the specific presence of Eimeria bovis, E. zuernii and E.
alabamensis is of a major interest in aetiologic diagnosis. Associated nematodes parasitism, very underestimated risk
factor by immune deviation, are also researched. So 6 vet clinics in 14 dairy and beef cattle farms have collected
samples in 53 groups of 5 calves under monitoring.
Results
39 groups reveal coccidiosis: so the herd prevalence is 83%. 88% of the 39 groups are infected with E. bovis, 75% with
E. zuernii and E. alabamensis; mixed infections by these 3 pathogen species have been described. In both types of cattle
production, the mean of the first significative E. oocysts excretion appears between Weeks 4 and 5, with a peak between
Weeks 5 and 6. The only nematode diagnosed in 25% of the groups is Strongyloides papillosus. Its presence depends of
the farm group and seems to be highly dependant of herd management.
Discussion
This survey clearly shows thay, even if occurrence of clinical coccidiosis may be possible precociously from Week 3,
the mean of significant oocyst excretion appears between Weeks 4 and 6. The early onset of coccidia shedding in field
conditions seems challenged by these results: the peak of oocystal excretion is not observed before the 5th Week. So the
rational control of coccidiosis involves not treating too early, to encourage initial contact between host and the
coccidian species. With 25% of prevalence, S. papillosus seems to be more frequent than expected. It can appear from
Week 2 (probably following colostral infection) but quite always before coccidian excretion, mainly between Week 4
and 5. Strongyloidosis must be diagnosed by coprology and controlled if results are positive. Because of its early
infection of the calves, S. papillosus could probably impact the immunity building against coccidiosis by immune
deviation (Th2/Th1).
Evaluation of botanic active compounds on the coccidian excretion and the
growth performance of dairy calves fattened under Spanish conditions
B. MEDINA - Phytosynthèse, Riom, France
[email protected]
M. LLORDELLA - Agropecuaria de Guissona, Spain
F. COTS - ITPSA, Barcelona, Spain
Introduction
In beef specific fattening farms, a recent study carried out in France (Assié et al., 2007), showed that 19.9% of justbought fattening steers had diseases. The problem which affected mainly respiratory tract, appeared during the first two
weeks (13.5 days in average) after the allotment of the young animals. Therefore, the aim of this study was to evaluate a
preventing feeding program based on a plant extracts based feed additive (EMX®, 89600 ppm of terpens,
Phytosynthèse, France) on the health status and the performance of growth of young fattening dairy steers compared to
sulfamids based prophylaxis program.
Protocol
2 groups of 16 frison young dairy calves were involved from 2 weeks till 3 months of age. In the CTL group, calves
received a sulfamids (0.75%) supplemented milk-replacer. In the EMX group, the milk-replacer was supplemented with
7 kg/T of EMX®, and the starter feed supplemented with 2.4 kg/T of EMX®. Live weight (LW), dry matter
consumption, and faecal excretion were recorded every 3 weeks.
Results
At the end of the trial, the difference of LW is different (P<0.05), with an increase of 10.3 kg (+9%) in EMX® group
compared to CTL (125 vs 114.7 kg). The EMX® group of Holstein calves presented (P<0.05) higher performance of
growth, over the trial + 124.3 g/d (+15.8%). Both the supplementation of EMX® in the milk -replacer (7 g/kg), and in
the feed (2.4 kg/T) enhanced the total feed consumption by 18.1 kg (+12,1%). Over the trial, the Feed conversion rate
decreased by 3% in the EMX® group compared to CTL one. The supplementation of EMX® allowed decreasing from
20 to 41% the average coccidian excretion.
Conclusions
Considering the conditions of this trial, young dairy calves animals supplemented with plant extracts based feed
additive showed better performance and lower (NS) coccidian excretion count.
Additional feeding of herbs in lambs:
influence on shedding of Eimeria spp. and on weight gain
L. PODSTATZKY - AREC Raumberg-Gumpenstein, Wels, Austria
[email protected]
V. KRENN - Landesverband für Schafzucht und Haltung, Linz, Austria
Especially in organic farming the use of medicine is restricted and associated with a longer withdrawal time for milk
and meat. In this trial a complement feeding based on herbs was tested on a sheep farm for its efficacy against shedding
of Eimeria spp. and weight gain in lambs. The herbs were mixed into the pelletized lamb feed concentrate for the trial
group, the control group received the pelletized lamb feed concentrate without these herbs. Lambs with an age of one
week were included in the trial. Faecal samples were taken 4 weeks after starting, at weaning and 4 weeks after
weaning. Weight control was done in the first week, at weaning and 4 weeks after weaning. Lambs that did not reach
20 kg body weight at weaning (8 weeks of age) were weaned with 12 weeks of age. No difference could be observed in
oocyst output between the trial groups. The output decreased until weaning, after weaning the output decreased in the
trial group and increased significantly in the control group. In the trial group weight gain was always higher than in the
control group, although the differences were not significant. A significant higher body weight in the trial group could be
observed at 4 weeks after weaning especially in lambs weaned with 12 weeks.
Dictyocaulus viviparus:
a field study of parasite dynamics in regularly infested herds
P. CAMUSET - Yvetot, France
[email protected]
The causes of clinical dictyocaulosis in herds of adult dairy cows are poorly understood.
The parasite can be introduced into a naive herd from the surrounding environment via the Pilobolus fungus or through
the introduction of sub-clinical infected carrier animals. Previous investigations in France and the Netherlands
demonstrated the importance of the role of sub-clinical carriers in herds in which clinical episodes occur regularly.
In 2009, a field study was performed with monthly ELISA tests for Dictyocaulus antibodies between April and
December on bulk milk samples from ten herds previously investigated in 2008 following clinical outbreak.
In two herds, clinical episodes occurred. The optical density ratio (ODR) of the milk samples was greater than 0.6
during these outbreaks. However, the samples collected one month prior to those outbreaks were below the threshold
value to recommend anthelmintic treatment. The other herds with low ODRs did not show any clinical signs of
dictyocaulosis.
Monthly serological testing of 25 cows was performed in one herd. Faeces samples were collected from these cattle
during the first sampling visit and examined for the presence of first stage Dictyocaulus larvae using a McKenna device.
Six cows tested positive prior to turn out. Subsequently, faeces samples from these cows were examined monthly for
larvae using the same method.
The proportion of cows testing positive prior to turnout is much higher than that reported by Eysker (1994). The number
of larvae per gram (lpg) of faeces was mainly low (1 to 2 lpg) but could reach 20 lpg. Larval excretion ceased during
spring and summer but resumed for some cows between September and October. The ODRs of individual sera
generally remained low, lower for the sub-clinical carriers. This herd experienced no clinical episode despite the high
level of initial pasture contamination.
This preliminary study provides an initial step in the understanding of parasitic dynamics in an intensively grazed herd
in which dictyocaulosis is becoming endemic. Further investigations are warranted to determine the schedule of the
pasture contamination by sub-clinical carrier cows and the features of the pasture and environment which induce the
occurrence of a clinical episode.
New data on kinetics of infection by Besnoitiosis in cattle herds
from endemic and non-endemic french areas
J.P. ALZIEU - Laboratoire Départemental Ariège, Foix, France
[email protected]
P. JACQUIET, E. LIENARD, M. FRANC - ENV, Toulouse, France
Context and purpose of the survey
Bovine besnoitiosis, disease caused by the protozoan parasite Besnoitia besnoiti, shows an increased number of cases
and geographic expansion in cattle herds from France, Spain, Portugal, Italy and also new outbreaks in South Germany.
So the disease is spreading within the countries and to the north. Bovine besnoitiosis cause substantial losses among
cattle breeds due to decreased body conditions, infertility of bulls and death of heavy infected animals. The emergence
of Besnoitia is due to more intensive cattle trade and buy-in of the disease as a result of asymptomatic carriers, main
part of infected animals in the herds. Vectorial transmission by insects is thought to be the essential route of
contamination by mechanic "injection" of bradyzoites of Besnoitia. Besnoitiosis is considered since 2010 as an
emerging disease by the European Food Safety Authority (EFSA). The purpose of this study is primarly the
appreciation of the kinetics of infection in herds from endemic areas and in those of recent outbreaks, secondly to
compare data of neighbouring herds.
Protocol
Individual blood samples of all the animals, from 6 months of age have been collected in order to detect specific
antibodies by reliable diagnostic tools based on ELISA technology for screening of the infected animals: this study took
place consecutively during the winters 2009/2010 and 2010/2011.
Results
Prevalence remains often high and quite equal (over 50%) in herds of endemic areas showing endemic stability. Very
contasted situations appear in new outbreaks but it seems that Besnoitiosis infection can extend very rapidly within 2
years (until 60%!). More surprising are the very different cases of neighbouring herds with very variable prevalence. It
is highly probable, despite theorical easy movements of biting insects (stomoxes, tabanids, …), that these insects stay
nearby the animals and follow their moving. These results suggest a greater influence of internal transmission of
Besnoitia in a herd than crossed infections between neighbours herds. This fact has a high importance on the strategic
choice of Besnoitiosis prophylaxis. According to the initial level of internal contamination, several possibilities of
sanitary management are proposed. Moreover, in low levels of infection (<10%), rapid elimination,of sick animals even treated- and ocular kysts carriers and secondarily others infected animals (seropositive) seem to highly reduce
reinfection risks.
Speaking about genital inflammation rather than uterine infection
S. CHASTANT-MAILLARD - ENV Toulouse, France
[email protected]
L. DEGUILLAUME - UMR 1198 INRA/ENVA, Jouy en Josas, France and ENV Maisons-Alfort, France
Introduction
Uterine health is one of the main factors limiting fertility and fecundity in dairy herds, with a major impact on
profitability. In Europe, the cost of post-partum uterine infections was estimated to amount to appr. 1.4 billion euros per
year (Sheldon et al., 2009). Moreover, the incidence of endometritis seems to be consistently rising over the years, as
indicated by the English National Animal Disease Information Service (NADIS) (Williams et al., 2008). In the UK, in
2006, about 6% of the cows were treated for endometritis which is close to the prevalence reported in France (5%)
(Bareille & Fourichon, 2006). Nevertheless, the recent development of a new diagnostic technique (cytology)
(Kasimanickam et al., 2004) demonstrated that endometritis was largely under-diagnosed and led to a new approach in
investigations on uterine infection. This paper focuses on bovine endometritis, now consensually defined as an uterine
infection observed 21 days post-partum with no associated systemic symptom (Sheldon et al., 2006).
Uterine involution is an inflammatory process
Immediately after calving, the uterine cavity of the cow is invaded by germs from the environment. Numerous bacterial
species can be isolated from uterine fluids at that time, especially Escherichia coli, Arcanobacterium pyogenes,
Pseudomonas aeruginosa, Pasteurella multocida, Streptococcus uberis, Staphylococcus aureus, Prevotella spp.
Fusobacterium necrophorum (Dohmen et al., 1995). Around 80-90% of the females are found to have a contaminated
uterusin the two first weeks following calving (Dohmen et al., 1995; Bekana et al., 1996; Sheldon et al., 2006). In
contrast with other species (Sheldon et al., 2004), uterine involution in the cow is a septic phenomenon. During the
post-partum period, immune defense mechanisms do clear the uterine cavity from this contamination so that bacterial
sterility is restored between 2 and 7 weeks after calving (Elliot et al., 1968; Hussain et al., 1990; Dohmen et al., 1995;
Sheldon et al., 2006). Numerous defense systems (anatomical, histological, immune, biochemical) are involved in this
bacterial clearance. The more important ones are cervical closure, endometrial regeneration, an increase in uterine pH,
myometrial contractions, and above all, bacterial phagocytosis by neutrophils, that massively invade the uterine cavity.
Indeed, the endometrium is equipped to identify the presence of bacteria in the uterine lumen: endometrial cells present
specific receptors (Toll-like receptors) recognizing the bacterial LPS (LipoPolySaccharid) toxin. This identification
triggers the synthesis by the endometrium of cytokines (e.g. Tumor Necrosis Factor, interleukins IL-1, IL-6, IL-8,
prostaglandins, leukotriens), that induce the diapedesis of circulating neutrophils into the uterine lumen (Bondurrant,
1999; Kim et al., 2005; Földi et al., 2006; Azawi, 2008; Singh et al., 2008; Davies et al., 2008). White cells will then
ensure the phagocytosis of bacteria, normally leading to complete sterilisation. Nevertheless, this process may not be
linear and several waves of bacterial elimination/growth seem to occur during the decontamination process (Lewis,
1997).
Uterine involution can thus be considered as a cellular inflammatory reaction. Of less importance is the humoral
response of the uterine mucosa. Antibodies against various pathogens (Campylobacter fetus, Histophilus somnus, BVD
virus and even A. pyogenes) have been identified in uterine fluids. Even though uterine IgG contribute to bacterial
phagocytosis through opsonisation and IgA limit bacterial adhesion to the endometrium, the importance of humoral
response in the uterine defense remains limited (Watson et al., 1990).
Uterine immune defense mechanisms are not at their best around calving
Umbilical cord rupture at fetal expulsion releases a flood of blood from the fetal placenta into the uterine lumen.
Among numerous actors of the immune system, this physiological hemorrhage brings factors from the complement
system, participating in bacterial opsonisation. Nevertheless, the presence of necrotic tissue together with the post
partum decrease in endometrial vascularization transform the uterine lumen into an anaerobic medium (El-Azab et al.,
1988), promoting the development of Fusobacterium necrophorum and Bacteroides spp. In turn, such anaerobes secrete
factors inducing the multiplication of A. pyogenes, whose concentration is directly linked to the severity of the
endometritis. Moreover, the proportion of T lymphocytes in peripheral blood is 45% at mid-lactation versus 20% only
around calving time. At that time, the proportion of stimulating T CD4+ lymphocytes decreases, to the benefit of
suppressive CD8+ lymphocytes (Shaffer-Weaver et al., 1997). Leukocyte phagocytic and cytotoxic activities are also
lower during the first week post-partum (Zerbe et al., 2000; Matteus et al., 2002; Cai et al., 2005; Kim et al., 2005).
Their progressive increase during the two following weeks probably plays a large part in the decontamination of the
uterus.
Why does a contamination turn into an infection?
When the balance between uterine immune defence and bacterial load is disrupted, the physiological contamination
becomes pathological. The imbalance occurs in case of abnormally high bacterial load, e.g. in case of placental
retention, manual exploration of the genital tract or vaginal tears. Surprinsingly, the hygiene level of the environment at
the time of calving seems to have very little impact on the uterine flora (Noakes et al., 1991). An imbalance may also
result from a fall in uterine defences. By themselves, uterine bacteria are immunosuppressive: Fusobacterium
necrophorum produces a leucotoxin and Prevotella melaninogenicus produces a substance inhibiting phagocytosis.
Pathological conditions in the dam are also associated with immunodepression: in case of placental retention (that is
associated with a more substantial decrease in the phagocytic competence of neutrophils during the first week after
calving (Cai et al., 1994) when (sub)clinical hypocalcemia reduces myometrial contractions or in case of severe
negative energy balance after calving. Indeed, decreased Insulin-like Growth Factor-I concentration, increased NEFAs
and BHB are known to have a negative effect on migration, phagocytic and bactericidal capability of neutrophils
(Suriyasathaporn et al., 2000).
The respect of the immune performance of the post-partum cow is thus a key element to limit the incidence of uterine
infections in a herd. This does not apply only to post-partum, but also to parturition, since the immune system seems
less efficient in cows that eventually develop an uterine infection compared to cows that remain healthy (Kim et al
2005; Hammon et al., 2006). Mobilisation of leukocytes through the uterine lumen together with the phagocytic activity
of the neutrophils is lower as early as one week before calving in cows with subsequent uterine infection (Cai et al.,
1996; Kim et al., 2005). Subclinical endometritis may thus be considered as a "production related disease". Recent
studies evidenced an association between subclinical endometritis and subclinical ketonemia (as a cause) and/or
subclinical mastitis (as an associated symptom of immune disorder) (Dubuc et al., 2010a; Cheong et al., 2011).
While uterine inflammation may be regarded as the result of poor efficiency of the anti-inflammatory system, some
recent experimental studies suggest that it may also reflect a suractivation of the pro-inflammatory system (Kim et al.,
2005; Herath et al., 2009; Chapwanya et al., 2009; Wathes et al., 2009). This emerging concept of endometritis as an
inflammatory disease due to an immune disorder was already evoked several decades ago. Instead of using antibiotics
to kill bacteria, Vandeplasshe (1987) suggested the potential use of blood derivatives such as heparinated blood, plasma
or even hyperimmune serum, delivered into the uterus, to provide active neutrophils. Other investigators suggested
stimulating local immunity by intra-uterine injection of a Lactobacillus suspension (Kummer et al., 1997),
administration of E. coli lipopolysaccharid (to induce neutrophil migration into the uterine lumen) (Singh et al., 2000)
or of lymphokins (Granulocyte-Macrophase Colony Stimulating Factor GM-CSF) to promote proliferation and
differentiation of granulocytes (Hussain & Daniel, 1991).
Inflammation rather than infection
Thus, both infection and inflammation should be considered as normal during post-partum uterine involution, although,
beyond a certain threshold, they may become pathological. Concerning the bacteriological aspecst, it appears difficult to
clearly discriminate between normal and abnormal bacteriological uterine content. In vitro, the number of colonies
growing from uterine liquids is usually limited and their pathogenicity is far from established, so that a large number are
classified as "potential pathogens" (Williams et al., 2005). By contrast, the threshold beyond which endometrial
inflammation is associated with impairment of reproductive performance is now better defined. Various thresholds have
been proposed in the literature to characterize cytological uterine inflammation, most of them ranging from 5 to 18% of
white cells in endometrial smears sampled around 30 DIM. A more severe inflammation is associated with a reduction
of first-service pregnancy rate, a decrease in pregnancy rate at 150 DIM, an increased median calving-to-conception
interval and an increased risk of culling for infertility (Kasimanickam et al., 2004; Gilbert et al., 2005; Parlevliet et al.,
2006; Barlund et al., 2008; Galvao et al., 2009; Dubuc et al., 2010b).
Such high proportions of neutrophils in endometrial smears define subclinical endometritis around D30 (Sheldon et al.,
2009), which is associated with a a long term effect on reproductive performance. But endometrial inflammation may
also affect reproduction with a short term effect: inflammation around the time of insemination is associated with lower
conception rates (Kaufmann et al., 2008; Salasel et al., 2010) and affects embryonic development, independently of any
bacterial content (Hill & Gilbert, 2008).
Interestingly, there is a lack of concordance between bacteriological and cytological findings (Földi et al., 2006; Lewis,
1997; Messier et al., 1984; McDougall, 2005). One may find bacteria without inflammation and conversely
inflammation without bacteria. Nevertheless, in the latter case, one may questions whether conventional
bacteriologicaltechniques, , with an initial step of bacterial culture, are appropriate. Metagenomics, as recently applied
to metritis cases, is most probably a very powerful tool, to better describe the bacterial population in subclinical
endometritis cases (Santos et al., 2011).
Not only the uterus, but also the cervix?
Apart from endometrial inflammation, cervical inflammation is also suspected to affect reproductive performance, but
few studies have been designed to evaluate the prevalence of cervicitis and its impact on bovine reproduction. Among
1000 cases of failure to conceive, Gloor (1967) diagnosed 126 cows affected by clinical cervicitis (edema of the
cervical os, mucosal congestion, enlargement of the cervix, presence of pus flecks in the vagina). Gonzalez et al. (1985)
reported 44% of non-pregnant cows affected by cervicitis, diagnosed by histological examination. Stephens et al. (1986)
were the first to propose a threshold for endocervical inflammation (5%N), but without experimental demonstration,
(only by similarity with endometrial inflammation). Ahmadi et al. (2006) reported no significant difference between
percentages of polymorphonuclear cells in cervical and uterine mucosa, and thus proposed endocervical cytology as an
easy-to-perform alternative for diagnosis of endometritis in cows and in ewes (Ahmadi et al., 2004, 2006). In our hands,
cytological cervicitis during the post-partum period was high in prevalence (42%) and had a major impact on
subsequent reproductive performance (Deguillaume et al., 2010).
Diagnosis of uterine inflammation in the field
While cytology provides an objective and quantitative description of the inflammatory status of the uterus, it also
represents a potential tool for diagnosis of endometritis. However, in the field, it remains difficult to perform, mainly
due to the delay between sampling and diagnosis. Two surveys on current practice of French veterinarians in the field
revealed that more than 70% of them based their diagnosis on the result of a combination of techniques, mostly
transrectal palpation, and examination of vaginal discharge (Charpentier, 2009; Troitzky, 2010). It is thus of practical
interest to investigate the value of commonly used diagnostic procedures such as transrectal palpation, transrectal
ultrasonography, and examination of vaginal discharge with reference to endometrial cytology. It now appears that the
examination of vaginal discharge may be the best predictor of endometrial cytology, and thus of subsequent
reproductive performance. Nevertheless, at best, it allows the identification of around 60% of affected cows. Other
criteria are of even lower predictive value (Barlund et al., 2008; Deguillaume et al., 2008; Senosy et al., 2011).
In conclusion, thanks to the cytological approach, concepts around endometritis are currently in a total renewal. Instead
of being regarded as a strictly bacteria-based disease, endometritis is now rather considered as an inflammatory disease,
expressing an imbalance between pro- and anti-inflammatory processes, in a context of a relative immune depression.
These new pathogenic approaches should lead to explore new therapeutic options.
References
Ahmadi MR et al. - Cytological studies of uterus and uterine cervical mucosa by swab and aspiration methods in cows.
J Fac Vet Med Univ Tehran, 2004, 59:360-366.
Ahmadi MR, Nazifi S - Evaluation of reproductive status with cervical and uterine cytology in fat-tailed sheep. Comp
Clin Pathol, 2006, 15:161-164.
Azawi OI - Postpartum uterine infection in cattle. Anim Reprod Sci., 2008, 105, 3-4:187-208.
Barlund CS et al. - Comparison of diagnostic techniques for postpartum endometritis in dairy cattle. Theriogenology,
2008, 69, 6:714-23.
Bekana M, Jonson P, Kindahl H - Intrauterine bacterial findings and hormonal profiles in post-partum cows with
normal puerperium. Acta Vet Scand, 1996, 37: 251-263.
Bondurant RH - Inflammation in the bovine female reproductive tract. J Anim Sci, 1999, 77 Suppl 2:101-10.
Cai TQ et al. - Association between neutrophil functions and periparturient disorders in cows. Am J Vet Res, 1994, 55,
7:934-943.
Chapwanya A et al. - Histopathological and molecular evaluation of Holstein-Friesian cows postpartum: Toward an
improved understanding of uterine innate immunity. Theriogenology, 2009, 71:1396-1407.
Charpentier L - Le suivi de reproduction des bovins en France : pratiques des vétérinaires et des éleveurs en 2008.
Veterinary thesis, Maisons-Alfort, 2009.
Cheong SH et al. - Cow-level and herd-level risk factors for subclinical endometritis in lactating Holstein cows. J Dairy
Sci, 2011, 94, 2:762-70.
Davies D et al. - Toll-like receptor and antimicrobial peptide expression in the bovine endometrium. Reprod Biol
Endocrinol, 2008, 18, 6:53.
Deguillaume L et al. - Comparative evaluation of various techniques for diagnosis of chronic endometritis in cows.
WBC Budapest, 2008:186.
Deguillaume L et al. - Impact of post-partum cervicitis on reproductive performance of dairy cows. ESDAR, Eger,
Hungaria, 2010.
Dubuc J et al. - Definitions and diagnosis of postpartum endometritis in dairy cows. J Dairy Sci, 2010, 93, 11:5225-33.
Dubuc J et al. - Risk factors for postpartum uterine diseases in dairy cows. J Dairy Sci, 2010, 93, 12:5764-71.
El-Azab MA et al. - Evaluation of the uterine environment in experimental and spontaneous bovine metritis.
Theriogenology, 1988, 29, 6:1327-1334
Elliott L et al. - Uterus of the cow after parturition: bacterial content. Am J Vet Res, 1968, 29, 1:77-81.
Galvao KN et al. - Effect of prostaglandin F2alpha on subclinical endometritis and fertility in dairy cows. J Dairy Sci,
2009, 92:4906-4913.
Gloor H - Cervicitis als Sterilitätsursache (Cervicitis as a cause of sterility). Schweiz Arch Tierheilkd, 1967, 109:574579.
Gonzalez HE et al. - Morphometric studies of the bovine uterus: microscopic lesions and retrospective reproductive
history. Am J Vet Res, 1985, 46:2588-2595.
Hammon DS et al. - Neutrophil function and energy status in Holstein cows with uterine health disorders. Vet Immunol
Immunopathol, 2006, 113:21-29.
Herath S et al. - Expression of genes associated with immunity in the endometrium of cattle with disparate postpartum
uterine disease and fertility. Reprod Biol Endocrinol, 2009, 29:7-55.
Hill J, Gilbert R - Reduced quality of bovine embryos cultured in media conditioned by exposure to an inflamed
endometrium. Aust Vet J, 2008, 86:312-316.
Hussain AM, Daniel RC - Bovine endometritis: current and future alternative therapy. Zentralbl Veterinarmed A. 1991,
38, 9:641-51.
Hussain AM, Daniel RCW, O’Boyle D - Post-partum uterine flora following normal and abnormal parturition.
Theriogenology, 1990, 37:1253-1267.
Kasimanickam R, Duffield TF, Foster RA, Gartley CJ, Leslie KE, Walton JS, Johnson WH. Endometrial cytology and
ultrasonography for the detection of subclinical endometritis in postpartum dairy cows. Theriogenology, 2004, 62(12):9-23
Kaufmann TB et al. - Prevalence of bovine subclinical endometritis 4h after insemination and its effects on first service
conception rate. Theriogenology, 2009, 71:385-391.
Kim IH, Na KJ, Yang MP - Immune response during the peripartum period in dairy cows with post-partum
endometritis. J Reprod Dev, 2005, 51:757-764.
Kummer V et al. - Stimulation of cell defense mechanism of bovine endometrium by temporal colonization with
selected strains of lactobacilli. Vet Med (Praha), 1997, 42, 8:217-24
Lewis GS - Health problems of the post-partum cow. Uterine health and disorders. J Dairy Sci, 1997, 80, 5:984-994.
Matteus L et al. - Blood and intra uterine leukocyte profile and function in dairy cows that spontaneously recovered
from postpartum endometritis. Reprod Dom Anim, 2002, 37:176-180.
McDougall S - Gross abnormalities, bacteriology and histological lesions of uteri of dairy cows failing to conceive or
maintain pregnancy. NZ Vet J, 2005, 53:253-256.
Messier S, Higgins R, Couture Y, Morin M - Comparison of swabbing and biopsy for studying the flora of the bovine
uterus. Can Vet J, 1984, 25:283-288.
Noakes DE, Wallace L, Smith GR - Bacterial flora of the uterus of cows after calving on two hygienically contrasting
farms. Vet Rec, 1991, 128, 19:440-2.
Parlevliet JM et al. - Prevalence of subclinical endometritis in Dutch dairy cows and its effect on fertility. Reprod
Domest Anim, 2006, 41:353.
Salasel B, Mokhtari A, Taktaz T - Prevalence, risk factors for and impact of subclinical endometritis in repeat breeder
dairy cows. Theriogenology, 2010, 15, 74, 7:1271-8.
Santos TM, Gilbert RO, Bicalho RC - Metagenomic analysis of the uterine bacterial microbiota in healthy and metritic
postpartum dairy cows. J Dairy Sci, 2011, 94, 1:291-302.
Senosy W et al. - Evaluation of Reproductive Tract Infection During Early Post-Partum Period and Its Relationship
with Subsequent Reproductive Performance in High Milk Producing Dairy Cows. Reprod Domest Anim, 2011, 24. doi:
10.1111/j.1439-0531.2011.01829.x
Shaffer-Weaver KA, Sordillo LM - Bovine CD8+ suppressor lymphocytes alter immune responsiveness during the
post-partum period. Vet Immunol Immunopath, 1997, 56:53-64.
Sheldon IM et al. - Defining postpartum uterine disease and the mechanisms of infection and immunity in the female
reproductive tract in cattle. Biol Reprod, 2009, 81:1025-32.
Sheldon IM, Dobson H - Post partum uterine health in cattle. Anim Reprod Sci, 2004, 82-83:295-306.
Sheldon IM et al. - The relationship between bacteriological and clinical findings with subacute/chronic endometritis.
Theriogenology, 1995, 43:1379-1388.
Sheldon IM et al. - Defining post-partum uterine disease in cattle. Theriogenology, 2006, 65:1516-1530.
Sheldon IM et al. - Influence of uterine bacterial contamination after parturition on ovarian dominant follicle selection
and follicle growth and function in cattle. Reproduction, 2002, 123:837-845.
Stephens LR et al. - Investigation of purulent vaginal discharge in cows, with particular reference to Haemophilus
somnus. Aust Vet J, 1986, 63:182-185.
Singh J et al. - The immune status of the bovine uterus during the peripartum period. Vet J, 2008, 175, 3:301-9.
Singh J et al. - Effectiveness of lipopolysaccharide as an intrauterine immunomodulator in curing bacterial endometritis
in repeat breeding cross-bred cows. Anim Reprod Sci, 2000, 59, 3-4:159-66.
Suriyasathaporn W et al. - Hyperketonemia and the impairment of the udder defense: a review. Vet Res, 2000, 31:397412.
Troitzky K - Enquête sur les méthodes de diagnostic et de traitement des endométrites chez la vache en France.
Veterinary thesis, 2010, Maisons-Alfort.
Vandeplasshe M - Immunité et métrite. Rec Med Vet, 1987, 163, 2:127-133.
Wathes DC et al. - Negative energy balance alters global gene expression and immune responses in the uterus of
postpartum dairy cows. Physiol Genomics, 2009, 39:1-13.
Watson ED, Diehl KK, Evans JF - Antibody response in the bovine genital tract to intrauterine infusion of Actinomyces
pyogenes. Res Vet Sci, 1990, 48:70-75.
Williams EJ et al. - Clinical evaluatiuon of post-partum vaginal mucus reflects uterine bacterial infection and the
immune response in cattle. Theriogenology, 2005, 63:102-117.
Williams EJ et al. - Effect of Escherichia coli infection of the bovine uterus from the whole animal to the cell. Animal,
2008, 2:1153-57.
Zerbe H et al. - Altered functional and immunoiphenotypical properties of neutrophilic granulocytes in post-partum
cows associated with fatty liver. Theriogenology, 2000, 54 :771-786.
Establishment of a standard operating procedure
for prediction of the time of calving in cattle
D. STREYL - Clinic for Ruminants, University of Munich, Germany
[email protected]
C. SAUTER-LOUIS, F. WEBER, H. ZERBE - Clinic for Ruminants, Oberschleißheim, Germany
Precise calving monitoring is essential to decrease consequences of dystocia for cow and calf. Two studies in healthy
cows compared seven clinical signs (broad pelvic ligaments relaxation, vaginal secretion, udder hyperplasia, udder
oedema, teat filling, tail relaxation, vulva oedema) alone and in combination in order to predict the time of parturition.
The relaxation of the broad pelvic ligaments combined with teat filling gave the best predictive value. In the proposed
parturition score (PS), a threshold of 4 PS-points was defined, below which calving within the next 12 h could be ruled
out with a probability of 99.3% in cows (95.5% in heifers). Above this threshold an intermitted calving monitoring
every 3 hours and a progesterone rapid blood test (PRBT) is recommended. By combining PS and PRBT (if PS " 4), the
prediction of calving within the next 12 h improved from 14.9% to 53.1% and the probability of ruling out calving was
96.8%. The PRBT was compared to a validated enzyme immuno assay (sensitivity: 90.2%; specificity: 74.9%). The
developed standard operating procedure, combining PS and PRBT, will enable veterinarians to rule out or predict
calving within the next 12 h in cows with a high exactness under field conditions (Supported by Pfizer Animal Health,
Pfizer Inc.)
Pregnancy-associated glycoprotein ELISA
as sensitive and specific laboratory based pregnancy test in cattle
M. PIECHOTTA - University of Veterinary Medicine, Clinic for Cattle, Hannover, Germany
[email protected]
H. BOLLWEIN, M. HOEDEMAKER - University of Veterinary Medicine, Clinic for Cattle, Hannover, Germany
C. EGLY - Idexx, Liebefeld-Bern, Switzerland
Early detection of nonpregnant cows can improve reproductive efficiency by minimizing the interval between detection
of nonpregnant animals and artificial insemination. Thus, reliable methods to identify nonpregnant dairy cows early
may play a key role to improve profitability on commercial dairy farms. Pregnancy-associated glycoproteins (PAGs)
measurement is used as blood parameter for early detection of pregnancy in cattle. The objective of the present study
was to determine test characteristics of a semi-quantitative PAG ELISA in pluriparous cows under field conditions
(pregnancy diagnosis using transrectal ultrasonography was defined as gold standard). Additionally, stability of PAG
proteins was tested in uncentrifuged samples (n=10).
Ultrasonography was conducted 30-107 days after artificial insemination (AI; 25-34 (n=62); 35-39 (n=87); 40-45
(n=61);>46 days after AI (n=87)) and>90 days post partum in 297 cattle from 5 farms. Concurrently, a blood sample
was collected for determination of blood PAG concentration (IDEXX, Westbrook, ME, USA).
Sensitivity of PAG based pregnancy diagnoses was 99.0%, specificity 91.4%, positive predictive value 96.7%, negative
predictive value 97.4% and accuracy 96.2%, respectively (n=290). The PAG assay classified 7 (2.4%) cows in a repeat
category. Two nonpregnant results using PAG were categorized as pregnant by ultrasound. Seven cows determined to
be pregnant using the PAG assay were categorized as not pregnant using ultrasonography.
PAG was detectable in whole blood containing EDTA for seven days (37°C) and>14 days (4°C), however, in two
previously pregnant tested cows the ELISA showed a questionable result after 7 days incubation (37°C).
In conclusion, the PAG blood pregnancy assay was a sensitive and specific method to detect pregnancy in cattle and
PAG is stable in whole blood for at least three days at 37°C.
Managing heat stress in dairy cattle: occurrence & control
J. NOORDHUIZEN - Vacqa-International, St Georges du Vièvre, France
[email protected]
J.M. BONNEFOY - Replonges, France
Heat stress problems in dairy cattle are rather common in tropical and subtropical regions. Over the last decade,
however, we have observed several days and even periods of heat stress in European countries too, affecting both
humans and cattle. While in the former regions dairy farmers may be used to handle such problems more or less
adequately, it is not sure that European farmers, or their veterinary practitioners, are sufficiently prepared to diagnose
and to deal with those problems, nor that they understand the consequences of heat stress for the dairy cattle, such as in
the area of metabolism in general, and of production, reproduction and health in particular. Especially high yielding
cows are susceptible, due to the increased level of their metabolism.
This paper presents the occurrence of heat stress, its signs and diagnosis, and major practical management measures to
control and to prevent heat stress. These measures can be divided into general measures (a Good Heat Stress code of
practice) and farm-specific measures (the application of cooling cycles). It is concluded that many management
measures are general in nature for which veterinarians may play the role of consultant-coach. Moreover, the most
adequate solution to repeated heat stress problems on dairy farms, in terms of applying cooling cycles and the necessary
equipment, is the tailor-made, individual farm approach.
Identification of the transmission model of Streptoccus uberis in a dairy herd:
are dynamic measurement and genotyping useful techniques?
E. SCHMITT-VAN DE LEEMPUT - Villaines la Juhel, France
[email protected]
C. GUIDARINI - Boehringer Ingelheim, Reims, France
Y.H. SCHUKKEN - QMPS, Ithaca, NY, USA
R. ZADOCK - Moredun Research Institute, Penicuik, Scotland
Infection of the mammary gland by Streptococcus uberis can take place through different transmission routes:
environmentally and contagious from cow to cow. Knowing the method of transmission in a herd is important for the
implementation of mastitis control programs: control measures are different for contagious mastitis than for
environmental mastitis. In this abstract a study is described to investigate whether two new techniques, dynamic
measurements and genotyping, can improve the identification of the transmission model of S. uberis in dairy herds
compared to classical milk quality audits. Ten dairy herds (40 to 80 dairy cows) with dominant presence of S. uberis
were included in the study. Classical milk quality audits (observation of buildings, management, milking routine and
udder lesions) were performed and milk samples of infected cows (SCC>200.000 cells/ml) were analyzed for the
presence of S. uberis. The milking machine was subjected to dynamic measurement: i.e. the level and stability of
milking vacuum were measured at several positions and times during milking as well as the pulsation to analyze
milking efficacy. In case of a satisfactory dynamic test, the milking machine was not considered as a risk factor.
Genotyping was performed on all S. uberis isolates (3 to 10 per farm). In this study, contagious transmission was
defined by the presence of one dominant genotype, and environmental transmission by the presence of numerous
genotypes. The conclusions of the classical milk audit and the two new techniques were compared to the clinical
observation that was used here as the reference method. The clinical observation was based on the results of the mastitis
control measures that were put in place: for example if the control measures were oriented towards contagious
transmission and were successful in diminishing the milk quality problems, the clinical observation would be
"contagious mastitis". In relation to clinical observation, dynamic measurements and genotyping improved the accuracy
of the diagnosis of the method of transmission by 20 and 40% respectively. It can be concluded that both dynamic
measurements and genotyping may contribute to our diagnoses of the dominant transmission route of S. uberis in a
dairy herd.
Current concepts and future developments in surgery,
anaesthesia and pain management
A. STEINER - Clinic for Ruminants, Vetsuisse Faculty, Berne University, Switzerland
[email protected]
This presentation aims to provide an overview of current concepts and future developments in surgery, anaesthesia and
pain management. This Information has been obtained from several discussions amongst peers and may not be
supported by published material and remains, therefore, speculation in various aspects.
Surgical interventions
Today, the main focus in buiatrics is laid on herd health and production management, the main intention being keeping
herds healthy and preventing the development of disease. This principle is advocated in herds consisting of production
animals of low economic value as well as in herds of breeding animals of high economic value. Once diseased, cattle
belonging to these two different categories will most likely be treated completely differently. This includes surgical
interventions.
Low value cattle: interventions must be cost-effective. This means that such surgical interventions ought to be carried
out on the farm without needing additional personnel. This keeps the surgical stress to a minimum. The period for
preparation of surgery and the duration of surgery itself must be short. If antimicrobials and other drugs are used at all,
then those with the shortest withdrawal periods should be selected whenever possible. The prognosis of the intervention
ought to be favorable, otherwise the animal may be sent to slaughter without delay. In order to fulfill these
requirements, the standard of surgery may suffer significantly. Some farmers may even prefer a layperson to perform
certain interventions, although this is inacceptable from a legal and an ethical point of view (Atkinson et al., 2010;
Burnell & Reader, 2010). Examples of such interventions are:
• LDA: laparoscopy instead of laparotomy,
• deep septic processes of the feet: open amputation instead of resection of the sesamoid bone and the distal
interphalangeal joint, thus preserving the foot,
• teat obstruction: blind cut instead of theloscopic removal.
High value cattle: interventions must be successful and the distress for the animal ought to be kept to a minimum. Costs
and withdrawal periods are of limited concern or even irrelevant. Inhalation anaesthesia, diagnostic imaging techniques
(radiography, ultrasonography, scinitgraphy) are standard procedures. Such examinations and surgical interventions are
usually performed in a specialized clinic under optimal environmental conditions. Owners demand interventions that
require top level specialized training and techniques similar to those advocated in equine patients. Surgical interventions
are requested, even if the prognosis may initially be poor. Some owners even have insurance that will cover the
expenses for treatment. Examples of such interventions are:
•
•
•
•
fracture repair in heavy animals, using open reduction and internal fixation,
arthroscopic approaches to synovial infections,
repair of intrathoracic diseases,
use of mechanical suturing instruments such as stapling devices.
(Digital) teaching material
The food animal caseload and access to live animals are rather limited in veterinary schools of many different countries.
At the same time, the use of experimental animals for teaching purposes (training in invasive examination techniques
and surgical interventions) is limited by increasingly stringent animal welfare legislation. Because of these reasons, the
development and use of electronic teaching material and the institution of clinical skills labs are extremely important in
the practical clinical training of veterinary students and will increase in the future. Examples of such novel teaching
materials are:
• displaced abomasum: teaching CD of "surgeries of the abomasum in cattle" with video animations (Desrochers &
Harvey, 2002),
• fracture repair: teaching videos produced by AO Foundation,
• endoscopy: teaching DVD "atlas of bovine soft tissue endoscopy" with animations and endoscopic video
sequences (Schlup et al., 2010),
• radiography: interactive teaching DVD "bovine radiology - digital diagnostic atlas" (Steiner et al., 2010),
• day one skills: Clinical Skills Lab of the Royal Veterinary College (Steiner et al., 2010),
• abdominal anatomy: haptic cow for teaching bovine abdominal anatomy and bovine rectal palpation (Baillie et
al., 2010).
Anaesthesia and pain management
Pain is evoked by a noxious stimulus, activating nociceptors in the periphery of afferent nerves (transduction of pain).
These nerves transport the stimulus to the dorsal horn of the spinal cord (transmission of pain). There, it is modulated
by nerves in the grey matter of the CNS (modulation of pain) before being transported by afferent nerves in the white
matter of the CNS to the brain, where pain is being perceived (perception of pain). Transduction of pain may be reduced
by NSAIDs, transmission may be blocked by local anaesthetics and reduced by alpha2-receptor agonists, modulation of
pain may be influenced by alpha2-receptor agonists and ketamine and perception of pain by ketamine. Pain relief is
expected to be optimal, if the development of pain is blocked concurrently at multiple sites. This concept is called
multimodal analgesia. It currently represents the gold standard in small animal pain management. It will most likely be
introduced into buiatrics in the near future.
The development of postoperative hypersensitivity is blocked, by the preoperative und perioperative administration of
pain killers. Recent studies in cattle show that this concept is valid for orthopaedic (Feist et al., 2008; Offinger et al.,
2011) as well as zootechnical interventions in cattle (Stilwell et al., 2008; Duffield et al., 2010) and may be introduced
into daily practice in the near future. Currently, the use of analgetics in cattle practice is still very limited.
Animal Welfare Acts of some countries already prohibit castration and debudding without adequate anaesthesia. This
will most likely be standard throughout Europe within a decade.
Summary and conclusions
The veterinary profession has been markedly influenced in the past and will further be influenced in the near future by
the rapid development of the cattle industries during the past decade, driven by the low market prices of food products
of animal origin and the high standards of animal welfare and food safety requested by the consumers and implemented
in the animal welfare and food safety acts of many countries.
The clinical teaching of students, using live animals and clinical cases is increasingly difficult and adequate pain
management will become routine in the future. In practice, immediate culling of cattle already at the beginning of a
disease process will more and more replace treatment trials in cattle of low economic value. On the other hand, top level
surgical skills are expected to be offered to salvage cattle of high economic value.
These forecasts might force many veterinary schools to critically review their veterinary curriculum.
References
Atkinson O et al. - Digit amputation by lay foot trimmers. Vet Rec, 2010, 167:877.
Baillie S et al. - Evaluating an automated haptic simulator designed for veterinary students to learn bovine rectal
palpation. Simul Healthc, 2010, 5:261-266.
Burnell M, Reader J - Digit amputation by lay foot trimmers. Vet Rec, 2010, 167:985.
Desrochers A, Harvey D - Surgeries of the abomasum in cattle. Audio-Video-3D CD, Université de Montréal, 2002.
Duffield TF et al. - Reduction in pain response by combined use of local lidocaine anesthesia and systemic ketoprofen
in dairy calves dehorned by heat cauterization. Can Vet J, 2010, 51:283-288.
Feist M, Köstlin R, Nuss K - Klauenoperationen beim Rind: Vorteile der perioperativen Analgesie. Tierärztl, 2008, 36
(G): 367-376.
Offinger J et al. - Efficacy of perioperative meloxicam in combination with intraoperative local anaesthesia in dairy
cows undergoing resection of the distal interphalangeal joint. 8. Buiatrik-Tagung Oberschleissheim, 2011.
Schlup I et al. - Atlas of bovine soft tissue endoscopy. DVD, 2010, Vetsuisse Faculty, University of Berne, Switzerland.
http://www.dkv.unibe.ch/content/wiederkaeuerklinik/education_training/endoscopy_atlas/index_eng.html
Steiner A et al. - Bovine radiology - digital diagnostic atlas. DVD, 2010. Vetsuisse Faculty University of Berne,
Switzerland.
http://www.dkv.unibe.ch/content/wiederkaeuerklinik/education_training/radiology_atlas/index_eng.html
Stilwell G, Lima MS, Broom DM - Effects of nonsteroidal anti-inflammatory drugs on long-term pain in calves
castrated by use of an external clamping technique following epidural anesthesia. Am J Vet Res, 2008, 69:744-750.
Evaluation of three different methods for anaesthesia
of calves in umbilical surgery
M. METZNER - Clinic for Ruminants with Ambulatory and Herd Health Services, Ludwig-Maximilians-Universität,
Munich, Germany
[email protected]
A. HEFTI, I. SCHLEMMER, C. SAUTER-LOUIS, W. KLEE - Clinic for Ruminants with Ambulatory and Herd Health Services,
Ludwig-Maximilians-Universität, Munich, Germany
The objective of this study was to compare the effects of three anaesthetic protocols: injection (INJ) with xylazine,
ketamine and local anaesthesia; a combination of injection and inhalation (KOM) with xylazine, ketamine, and
isoflurane; and inhalation with isoflurane alone (INH) in groups of calves with (test group [c]) or without surgery
(control group [o]). During the trial, signs of response to surgical stimulation or spontaneous movements, changes in
heart rate, mean arterial pressure, and plasma lactate and cortisol levels were recorded.
The dosage of 5 mg ketamine/kg body mass was rarely sufficient to obtain surgical tolerance (CT) in group INJ. In
order to attain CT, it was necessary to administer an average of 8.4 mg ketamine/kg body mass. All animals of the
INJc/o groups started to show signs of spontaneous movements or response to surgical stimulation between 5 and 12
minutes after the last administration of ketamine. Signs of response to surgical stimulation at the time of skin incision
were significantly most frequent (37%) in the INHc group, while agitation or response to surgical stimulation at least
once during the entire time of anaesthesia was significantly most frequent in the INJc group (100%).
Heart rate and mean blood pressure were not found to be related to surgical stress situations. Significant increases in
blood cortisol levels were determined in all groups, and the greatest increases above basal levels of the previous day
occurred ten minutes after incision in the groups INJc and INJo: 53.5 and 57.7 nmol/l, respectively. However,
significant differences between the experimental and control groups were found only in the INH groups between the
previous day and HS+10 minutes, and between ten minutes after skin incision and at the end of anaesthesia (30.1 versus
7.5 and 27.3 vs 4.7 nmol/l, respectively). Within the experimental groups only the increase between the previous day
and ten minutes after incision between the INJc and KOMc groups was significant (53.5 vs 28.3 nmol/l).
Blood composition parameters in calf from birth to 60 days
K. MAXIMIN - VetAgroSup, Marcy l’Etoile, France
[email protected]
M.A. ARCANGIOLI - VetAgroSup, Marcy l’Etoile, France
Many changes occur in cattle blood composition during the first weeks of life, with leading part of breed and milk
composition. These changes may interfere with an accurate diagnosis impeding the interpretation of clinical pathology
data.
To get some references, blood composition of 21 calves were followed during the first eight weeks. These calves, nine
charolais and 12 montbeliard, supplied with total cow milk (from their mother or the bulk tank milk), were blood
sampled on day 0, 8, 30 and 60. An automated cell counter measured complete blood count with cell counts and red
blood cell parameters (Hb, PCV, MCH, MCHC, MCV). Differential leukocyte count was performed on stained blood
film (kit RAL 555).
Results show a moderate anemia in all the calves, with a fall of hemoglobin and MCHC, slightly compensated by an
increase of the erythrocytes’ count. Total leukocyte count reference range and its evolution along the time were
impossible to assess due to the wide dispersion of the leukocyte counts results. Neutrophil granulocytes proportion of
95% occur the day of birth (D0) and then neutrophil count diminished. So, the neutrophils to lymphocytes ratio
decreases the first week and enters in the reference values. Platelet count was difficult due to a strong anisocytosis. This
platelet count increases the first week until the reference interval values.
To conclude, interpretation of complete blood count the first weeks of life has to consider the natural moderate anemia
and the platelet anisocytosis. Leukocyte count cannot be interpreted, and differential leukocytes count can be of use
only after the first week of life.
Surgical treatment of severe udder infection by vascular ligature in cow
G. BELBIS - Université Paris-Est, Ecole Nationale Vétérinaire d’Alfort, Maisons Alfort, France
[email protected]
X. QUENTIN - Bourgtheroulde Infreville, France
N. CREVIER-DENOIX - Université Paris-Est, Ecole Nationale Vétérinaire d’Alfort, Maisons Alfort, France
S. CHASTANT-MAILLARD - ENV Toulouse, France
In case of an extremely intense mastitis in a cow with systemic repercussion (chronic suppurative mastitis, gangrenous
mastitis…) and without any response to medical treatment, only few surgical techniques are available for practitioners.
Complete or hemi-mastectomy is complicated, and euthanasia is often the only solution.
An alternate surgical procedure consists in ligating the different vessels providing blood supply to the mammary gland
(external pudendal vessels, ventral perineal vessels and subcutaneous abdominal vein). In the presented technique, all
blood vessels are ligated because of surgical failure observed, in our practice, when ligating only external pudendal
vessels despite of an adequate ligature (confirmed by a Doppler exam performed during surgery).
External pudendal arteries and veins are approached by a flank laparotomy. Classical local anaesthesia and surgical
preparation of the paralumbar fossa is performed, and a flank laparotomy realised. After localisation of these vessels, a
blunt dissection is performed in order to separate them from the peritoneal membrane. This dissection is performed
close to the place vessels enter the internal inguinal ring. Finally, ligature is performed with a rubber band (1 cm large)
cut in half. The same operation is performed on the controlateral vessels.
In order to ligate ventral perineal vessels, an epidural anesthesia is performed. Surgical site is located in midsagittal
plane of perineal area, roughly 20 cm below ischial tuberosity. After skin incision, subcutaneous tissue is dissected and
vessels isolated, then ligated routinely with surgical wire. Skin is closed routinely.
Finally, subcutaneous abdominal veins need to be ligated. The surgical area, roughly a hand (8-10 cm) from the
mammary gland, is clipped (5 cm long), and local anesthesia is administered in line block, on both sides of the vein.
After skin incisions, subcutaneous tissues are dissected until reaching the other side. A rubber band, cut in half, is then
passed behind the vein, and tightened. The same surgical procedure needs to be performed on the other side because of
the presence of a venous ring formed above the base of the udder by transverse connections between paired veins.
In conclusion, this surgical procedure can be performed rapidly and easily, and constitute an alternative to euthanasia.
Long term epidemiologic survey of sensitivity to antimicrobials
of pathogens involved in mastitis, respiratory or digestive disorders
in European cattle (1995-2009)
H. GIBOIN - Vétoquinol, Paris, France
[email protected]
S. KROEMER, D. GALLAND, F. WOEHRLE-FONTAINE - Vétoquinol, Lure, France
Pathogenic bacteria isolated from cattle cases of mastitis, diarrhoea or respiratory disease (BRD) in several European
countries were subjected to standard antibiogram testing. Each year since 1995, the strain collection has been expanded
with 300 to 1500 strains a year (over 10000 strains collected in total). Samples originated from cases prior to
antimicrobial treatment, and were systematically identified and tested for sensitivity to a range of relevant antibiotics.
From mastitis cases, Escherichia coli, Staphylococcus aureus, Staphylococcus coagulase negative, Streptococcus
uberis, S. dysgalactiae and S. agalactiae were most frequently collected, with rarer instances of Klebsiella spp.,
Pseudomonas aeruginosa, Pantoea spp., Arcanobacterium pyogenes and Corynebacterium bovis collection. Mastitis
strains were tested for sensitivity to several beta-lactams, quinolones, macrolides, tetracyclines and aminoglycosides.
From BRD cases, Mannheimia haemolytica, Pasteurella multocida, Mycoplasma bovis and Haemophilus somnus were
most frequently collected, but the M. bovis strains could not be subjected to standard antibiogram testing due to inherent
limitations of the technique (M. bovis strains had their marbofloxacin MIC systematically determined). Respiratory
strains were tested for sensitivity to several beta-lactams, quinolones, macrolides (or derivatives), phenicols,
sulphonamides, tetracyclines and aminoglycosides. From digestive cases, E. coli (serotyped or not), Salmonella spp., S.
Dublin and S. typhimurium were most frequently collected, with rarer instances of Proteus mirabilis collection.
Digestive strains were tested for sensitivity to several beta-lactams, quinolones, macrolides (or derivatives),
sulphonamides, tetracyclines and aminoglycosides.
Among mastitis and respiratory pathogens, the percentage of sensitivity to antibiotics was mostly stable from year to
year, with no overall trend of increase or decrease of sensitivity. Mastitis E. coli sensitivity to marbofloxacin ranged
from 95 to 100% during the period, sensitivity to amoxicillin from 61 to 89%, sensitivity to colistin from 88 to 100%.
From BRD samples, P. multocida sensitivity to marbofloxacin ranged from 96 to 100% during the period, sensitivity to
amoxicillin-clavulanic acid from 81 to 100%, sensitivity to oxytetracycline from 70 to 95%, sensitivity to trimethoprimsulfa from 84 to 100%. Among digestive strains of E. coli, there was a trend for decreased sensitivity to most antibiotics
over the years, with only colistin having conserved sensitivity levels in latest years.
Is Mannheimia haemolytica highly contagious among
newly-received bulls at fattening operations?
E. TIMSIT - LUNAM Université, ONIRIS, UMR 1300, Biology, Epidemiology and Risk Analysis, and INRA, Nantes,
France
[email protected]
H. CHRISTENSEN - Dpt of Veterinary Pathobiology, Faculty of Life Sciences, University of Copenhagen, Frederiksberg, Denmark
N. BAREILLE, S. ASSIE - LUNAM Université, ONIRIS, UMR 1300, and INRA, Nantes, France
Background
Mannheimia haemolytica is the principal bacterium isolated from the lung of cattle suffering from bovine respiratory
disease (BRD) in fattening operations. Despite the numerous studies of this bacterium, the source of M. haemolytica
that colonize the lung leading to a pneumonic pasteurellosis is still debated. On one hand, cattle can become infected by
exposure to infected nasal secretions from other infected penmates. On the other hand, because M. haemolytica is a
normal inhabitant of the nasopharynx of healthy cattle, it can also recrudesce from carriers rather than being transferred
among penmates.
Objective
The objective of this study was to determine if M. haemolytica isolates collected from bulls’ lungs during BRD episodes
occurring in fattening operations are clonally related (i.e. horizontally transferred among penmates) or, genetically
unrelated (i.e. recrudesced from carriers).
Materials and methods
12 groups of 8 to 12 beef bulls (n=112) aged from 7 to 13 months were studied during the 40 days following their
arrival at fattening operations. As soon as a BRD-affected bull was detected in a group, a trans-tracheal aspiration
(TTA) was performed on each bull of the group to isolate M. haemolytica. TTA was then repeated every 3 days on nontreated animal until no new BRD cases were detected in a group. M. haemolytica isolates were genotyped by pulsedfield gel electrophoresis (PFGE). PFGE profiles were analysed using Bionumerics ® software and the genetic diversity
of M. haemolytica isolates collected during BRD episodes was quantified using the Simpson’s index of diversity (SID).
Results
M. haemolytica isolates were collected during 14 BRD episodes. The prevalence of bulls positive for M. haemolytica on
TTA samples during these episodes ranged from 11% to 89% (mean = 60%). The genetic diversity of M. haemolytica
isolates was high (SID>0.50) in 12 of the 14 episodes with different genotypes involved in each episode. In 2 BRD
episodes, however, a single genotype predominated indicating a horizontal transfer of M. haemolytica among bulls.
Conclusion
Although M. haemolytica can be horizontally transferred among bulls, the data supports the idea that M. haemolytica is
not highly contagious among newly-received bulls at fattening operations.
Forced oscillation technique measurements of pulmonary function:
an objective tool to assess the respiratory function in cattle
J. PRINGLE - Swedish University of Agricultural Sciences, Uppsala, Sweden
[email protected]
S. HÄGGLUND, K.F. HU, B. KRISTER - Swedish University of Agricultural Sciences, Uppsala, Sweden
J.F. VALARCHER - Swedish National Veterinary Institute, Uppsala, Sweden
In this paper we present the evaluation of forced oscillation technique (FOT) as a tool to quantify clinical observations
during respiratory infection in cattle.
Pulmonary function was measured in calves vaccinated or not against bovine respiratory syncytial virus (BRSV), before
and after experimental BRSV infection. Four groups of five 3-8 week old calves with variable levels of BRSV-specific
MDA were immunized s.c. twice at a 3 weeks interval with:
•
•
•
•
BRSV-ISCOMs,
BRSV-protein,
adjuvant, or
PBS.
All calves were challenged with virulent BRSV by aerosol 2 weeks later and euthanized on PID 6. The forced
oscillation technique (FOT) was performed at 3, 5, 7 and 10 Hz (EquineOsc Calf measurement head EEMS Harts UK)
immediately prior to virus challenge and on post infection day 6. Calibration (tube 2.26 m long x 21 mm internal dia)
was performed prior to each day’s measurements. Only data sets with coherence>0.9 (majority>0.97) were retained for
analyses. Data were compared using a directional paired T test (JMP2010 SAS Institute Inc), significance at p#0.05.
Results
By post infection day 6 only a minimum of clinical signs were observed in the BRSV-ISCOM group whereas calves in
all control groups had signs (cough, nasal discharge, abnormal sounds on lung auscultation, RR up to 76 per min and
RT up to 41 C) consistent with acute BRSV infection. On FOT was no significant impairment of pulmonary function in
the vaccinated group or in calves with low clinical scores, whereas nonvaccinated groups and those with high clinical
scores had significantly increased resistance and/or decreased reactance (P<0.05), mainly at lower frequencies. Thus
vaccinal protection against functional changes was consistent with clinical observations.
In conclusion, we demonstrate that FOT is an easy, robust and noninvasive technique that is useful to objectively
quantify clinical observations in calves with acute viral respiratory disease.
The prevalence of rib fractures and association with lameness in 13 dairy herds
R. BLOWEY - Wood Veterinary Group, Gloucester, UK
[email protected]
N. BELL - University of London, London, UK
E. BOYLING - University of Bristol, Bristol, UK
Previous studies (Blowey 2007, 2008) have anecdotally associated fracture at the costochondral junctions of the 7th-9th
ribs with lameness in dairy cows. A similar trauma associated lesion is found in cats. In the current study, after checking
for inter observer agreement, 1998 cows from 13 herds were physically examined by EB for palpable rib swellings
(PRS) during routine TB testing or fertility visits. Because of practical limitations on farm, some cows were examined
bilaterally and others unilaterally. Age and lameness scores were also recorded. The prevalence of PRS ranged between
3.6% and 26.8% of the cows examined in each herd, with 15.7% of cows affected overall. Cows with unilateral and
bilateral lesions were present in almost equal proportions. Multilevel modelling showed a high probability of a cow
having PRS with increased lameness score (P<0.001) and increasing age (P<0.001). The significance of this high
prevalence of rib fracture and/or PRS in relation to welfare is discussed.
Recent epidemiological insights on control of Q fever and paratuberculosis
M. NIELEN - Department of Farm Animal Health, Utrecht, NL
[email protected]
Both Q fever and Johne’s disease are caused by intracellular bacteria that are difficult to diagnose within the ruminant
host and may survive for long periods outside the host in the environment. Coxiella burnetii (Cb) is clearly a zoonotic
agent with a low infectious dose, while the role of Mycobacterium avium subsp. paratuberculosis (Map) in human
Crohn’s disease is debated.
The rise of human Q fever patients in the Netherlands from 2007-2009 was associated with Cb caused abortion
problems in small ruminant dairy herds, mainly dairy goats. Various control measures were implemented to reduce
human illness, including vaccination of dairy goats and sheep. The most drastic measure was the culling of all pregnant
dairy goats (and sheep) from herds positive for Q fever, in early 2010. We sampled around 1000 culled pregnant
animals from 6 unvaccinated and 7 vaccinated herds to study the effect of vaccination on Cb shedding (Hogerwerf et
al., 2011). We concluded that vaccination reduced both prevalence and bacterial load in vaccinated herds, thus
potentially reduced bacterial load in the environment and thereby human exposure. The human situation improved in
2010 and again in 2011, which indeed indicated that vaccination of small ruminant dairy herds had reduced
environmental transmission to humans. Currently, a mathematical model on within herd transmission of Cb in dairy
cattle (Courcoul et al., 2011) is being adapted. The goal is to study if the dairy goat herd dynamics could have resulted
in abortion clusters with high environmental Cb load, compared to the dairy cattle situation.
Map control in dairy cattle is an ongoing effort in many countries and generally consists of test and cull in combination
with specific bio secure young stock management. In the Netherlands, the focus of the control program for dairy cattle
was shifted towards containment, rather than eradication (Weber et al., 2008). In the large Dutch dairy goat herds,
vaccination is commonly used as a control tool, which is not feasible for dairy cattle due to interference with
tuberculosis diagnosis. Novel marker vaccines are under development (i.e. Santana et al., 2009), but are currently not
available in the field. Another longer term control approach could be genetic selection (Hulzen et al., 2011), although
heritability is rather low. To better understand transmission within dairy cattle herds, we sampled dust in commercial
dairy farms (Eisenberg et al., 2010). We observed that dust with viable Map is present at many locations within farms,
indicating a potential role of bioaerosols in transmission of Map to susceptible young stock. To elucidate if aerogenic
infection with Map is possible, we carried out an infection experiment with young calves, which were nasally and trans
tracheally challenged with Map (Eisenberg et al., 2011).
BTV and EHDV epidemiological situation
in the French Martinique and la Réunion Island
S. ZIENTARA - ANSES, Maisons-Alfort, France
[email protected]
C. SAILLEAU, C. VIAROUGE, E. BREARD - ANSES, Maisons-Alfort, France
Bluetongue virus (BTV) and Epizootic haemorrhagic disease virus of deer (EHDV) are two species of the genus
Orbivirus within the Reoviridae familly. The two viruses are morphologically, structurally and biologically similar.
Twenty-five serotypes of BTV and 8 serotypes of EHDV have been identified.
This paper describes the development of BTV and EHDV type-specific RT-PCR which have allowed to characterize
new strains isolated from the Martinique (in the Caribbean Sea) and the La Réunion Island (in the Indian Ocean).
In 2006, 30 cows (viro and seronegative for BTV) exported from France to the Martinique Island were sampled 10, 20
and 30 days post-importation. The sera were tested by a competition ELISA (BT C-ELISA IDvet) and EDTA blood
samples were used for PCR and viral isolation on embryonated eggs.
A sequence analysis of segments 2 (this segment 2 encodes VP2 which is the outer capsid protein involved in serotype
specific serological reactivity) of the 24 serotypes of BTV).
Thirty days post-importation, 56% of animals seroconverted and 80% were positive with a BTV group real-time RTPCR. The amplification products obtained with consensus primers from the RNA extract from isolated strains were
sequenced and allowed to type the serotypes: 2, 9, 10, 17, 18, 22 and 24.
Sequence analysis of these strains showed that the origin of these viruses is unknown and that the serotypes 2, 10 and
17 do not originate from America.
In 2009, BTV-like clinical signs were reported in cattle of the French la Réunion Island.
121 animals with clinical signs were sampled. EDTA blood samples were used for BTV, EHDV-group-specific RTPCR and viral isolation on embryonated eggs.
By BTV and EHDV-group-specific RT-PCR, 120 animals were detected as EHDV RT-PCR positive and 5 animals
BTV and EHDV RT-PCR positive; moreover, one strain of BTV and 7 strains of EHDV were isolated in embryonated
chicken eggs. The BTV virus was type as serotype 2.
The sequence of the amplification products (with the pair of primers specific of Group C) allowed to conclude that the
EHDV serotype was 6. Sequence data showed that these strain was the cause of the EHD outbreak in the Island in 2003.
This serotype 6 is also present in North Africa since 2006.
BRSV-ISCOMs induce clinical and virological protection
in young calves with maternal antibodies
S. HÄGGLUND - Swedish University of Agricultural Sciences, Dpt of Clinical Sciences, Uppsala, Sweden
[email protected]
K.F. HU, K. BLODÖRN, L. PORÉ, J. ANDERSON, J. PRINGLE, K. ELLENCRONA, K. VARGMAR, A.S. OLOFSON, P.
AHOOGHALANDARI - Swedish University of Agricultural Sciences, Uppsala, Sweden
G. TAYLOR - IAH, Compton UK
S. RIFFAULT, J.F. ELÉOUËT - VIM INRA, Jouy en Josas, France
J.F. VALARCHER - Swedish National Veterinary Institute, Uppsala, Sweden
Bovine respiratory syncytial virus (BRSV) continues to be a major pathogen in the respiratory disease complex of cattle
and causes yearly outbreaks with high morbidity in Europe. It is urgent to develop efficient vaccines against BRSV
since available products do not offer optimal protection, especially not in calves with BRSV-specific maternally derived
antibodies (MDA). Safety problems have also occurred with killed vaccines in calves.
We have previously demonstrated that an experimental BRSV-ISCOM vaccine, but not a commercial vaccine, induced
clinical and virological protection in calves with MDA, immunized at 7-15 weeks of age. The aim of the present study
was to characterize the immune responses induced by BRSV-ISCOMs, as well as to investigate the efficacy and safety
in younger animals, representing the target population for vaccination.
Four groups of five 3-8 week old calves with variable levels of BRSV-specific MDA were immunized s.c. twice at a 3
weeks interval with:
•
•
•
•
BRSV-ISCOMs,
BRSV-protein,
adjuvant, or
PBS.
All calves were challenged with virulent BRSV by aerosol 2 weeks later and euthanized on PID 6. The cellular and
humoral responses were monitored as well as the clinical signs and the viral excretion following challenge. Despite
presence of MDA at the time of the immunization, only a minimum of clinical signs were observed in the BRSVISCOM group after challenge. In contrast, in all control groups, clinical signs of disease were observed in most of the
animals (cough, nasal discharge, abnormal sounds on lung auscultation, RR up to 76 per min and RT up to 41°C).
The clinical protection was associated to a highly significant reduction of virus replication in the upper and lower
respiratory tract of calves, rapid systemic and local antibody responses and T helper cell responses dominated by IFN!
production. The absence of clinical signs and the character of pulmonary cellular responses indicated good safety.
Moreover, the protective immunological responses to BRSV proteins and the ability to overcome the inhibiting effect of
MDA were dependent on ISCOM borne antigen presentation. A detailed characterization of the vaccine will
additionally be presented on the congress.
Outbreaks of jaundice in young calves - a novel disease?
M. METZNER - Clinic for Ruminants with Ambulatory and Herd Health Services, Ludwig-Maximilians-Universität,
Munich, Germany
[email protected]
M. LANGENMAYER - Institute of Veterinary Pathology, Ludwig-Maximilians-University, Munich, Germany
B. WEBER - Bavarian Health and Food Safety Authority, Oberschleissheim, Germany
M. WIELAND - Clinic for Ruminants with Ambulatory and Herd Health Services, Ludwig-Maximilians-Universität, Munich,
Germany
Since September, 2010, jaundice was noticed in up to 100% of young calves on twelve dairy farms in Bavaria.
Estimated case mortality rates reached 80%. The disease becomes apparent when the calves are between seven and 10
days old. They drink less, become listless, some have fever, and they become progressively weaker. After two to three
days, some become recumbent, and convulsions and loud bawling may occur. At this stage, they either die relatively
quickly, or are euthanized for humanitarian reasons. Surviving calves are reported to show stunted growth. In most
cases diarrhea occurred before the animals fell ill, but at this stage the feces were normal.
19 calves in different stages of the disease (varying from seemingly healthy to being in agony) from ten farms were
admitted to the Clinic. In early cases, clinical pathology revealed rapid rises in the activity of liver enzymes in serum
(maximal values recorded were 814 U/L for AST, 635 U/L for GGT, and 1696 U/L for GLDH. Concentrations of total
protein and albumin were below the reference ranges in many cases. There was no evidence of anemia. In later stages
the sclera became yellowish, and the concentration of bilirubin rose up to 323 $mol/L. Some calves developed
hypoglycemia. Copper, iron, and zinc concentrations in serum were within the respective reference ranges. In later
stages, some calves had fever, without any evidence of infections of the respiratory tract or navel.
Post-mortem examinations in 13 calves revealed a severe hepatopathy. The histologic lesions were massive disruption
of liver architecture including necrosis of hepatocytes and extensive bile duct proliferation in most of the affected
animals. These changes were accompanied by mild inflammation, fibrosis and intrahepatic cholestasis. Hepatocellular
icterus occurred in some cases. No specific alterations could be seen in other organs.
Examination of liversamples of two calves from different farms for Aflatoxin, Deoxynivalenol, Ochratoxin A and
Zearalenon and a toxicological screening by chromatography were unremarkable.
So far, the etiology of this disease has not been elucidated. Both intoxications and infections seem possible at this stage.
Assessment of the curative and preventive effectiveness of different practical
modalities of collective treatment of digital dermatitis in dairy herds
A. RELUN - ONIRIS, UMT Cattle Health Management, Nantes, France
[email protected]
R. GUATTEO, N. BAREILLE - ONIRIS, UMT Cattle Health Management, Nantes, France
A. LEHEBEL - ONIRIS, UMR BioEpAR, Nantes, France
Digital dermatitis (DD) is currently the major causes of infectious lameness in cattle. The reported incidence has
increased worldwide due to the enlargement and merger of dairy herds. DD is nowadays a serious issue for farmers
because the disease negatively affects both animal welfare and production. Among available collective treatments, those
with disinfectants are widely used, especially in large farms or in farms with high DD prevalence. A lot of practical
modalities have been described but their effectiveness seems to vary and they are not always convenient. The objective
of this study was to evaluate the preventive and curative effectiveness of 3 practical modalities of collective treatments,
without using formalin or copper sulphate, and their factors of variation. The modalities were [B] walking the cows
twice through a footbath containing a 5% multi-compound solution (Hoof-fit bath) on two days a week every 4 weeks
(11 farms) or [C] every 2 weeks (11 farms) and [D] spraying the hind feet with the 50% multi-compound solution
(Hoof-fit Liquid) in the milking parlour twice 4 days apart every 2 weeks (13 farms), for 28 weeks. In all groups, severe
DD lesions were treated individually with topical oxytetracycline. All hind feet were cleaned with a medium-pressure
hose before treatment. The effects of these modalities on incidence and cure of severe DD lesions were compared with
the effects of a control measure [A] consisting of only topical oxytetracycline treatment (17 farms). Follow-up visits
were carried every 4 weeks (just ending). During these visits, the hind feet of all lactating cows were scored for DD,
housing was scored for hygiene and data on management practices were collected. At the beginning of the experiment,
the proportion of M2-lesions on hind feet within farm ranged from 0 to 26%. The curative and preventive effectiveness
of different modalities will be compared using survival analysis (Cox model). Preliminary results indicate that the
prevalence of M2-lesions decreased in most of the farms in group C and D but not in group A and B. Preventive and
curative effectiveness will be presented at the conference together with practical considerations.
Dairy calf mortality in France in 2005 and 2006
D. RABOISSON - Université de Toulouse, INP, ENVT, US 0685, ODR, Toulouse, France
[email protected]
E. CAHUZAC, G. ALLAIRE - INRA US 0685, ODR, Toulouse, France
P. SANS - Université de Toulouse, INP, ENVT, Toulouse, France
To describe dairy calf mortality and its herd risk factor in France, farm level variables (including mortality rate, MORA) were calculated with the French Identification Database (2005 and 2006).
11 dairy production areas (breeding system) were included. Statistical analyses were performed with a probit (MORA=0 or>0) and linear model (MO-RA>0) corrected by the sample bias Heckman method.
For 0-2 days old calves (CA0D2D), 261,000 and 251,000 of 3.51 and 3.43 million born calves died for 2005 and 2006,
respectively; MO-RA(0-excluded) was 7 and 14%, and 26-27% and 52-53% of farms had at least one death, for non
crossed (NOCR) and beef-crossed calves (BECR), respectively.
For 3 days-1 month old calves (CA3D1M), 138,000 and 133,000 of 2.38 and 2.33 million calf-month died for 2005 and
2006, respectively; MO-RA(0-excluded) was 10 and 17% and 45% and 67% of farms had mortality, for NOCR and
BECR, respectively. 50,500-52,700, 35,400-35,000 and 40,900-40,300 heifers out of 1.1 million 3 days-1 month old
heifer-month (HEIF3D1M), 1.1 million 1-6 months old heifer-half-year (HEIF1M6M), and 943-854,000 6 months-first
calving heifer-year (HEIF6MC1) died, respectively; respective MO-RA(0-excluded) were 11, 10 and 13%; respective
farms with mortality were 60, 69 and 67%.
The same effects were reported between 2005 and 2006. MO-RA was significantly associated with purchased cow
proportion (positively), being a milk control program (positively) and a good breeding practice (negatively) member,
having an autumn calving peak (negatively). Effects of breed and areas differed among outcome variables. Having a
beef unit was negatively associated with MO-RA for NOCR-CA0D2D, NOCR-CA3D1M and HEIF3D1M, but
positively for BECR-CA0D2D, BECR-CA3D1M, HEIF1M6M and HEIF6MC1, suggesting that having beef cows
allow specific competencies, but these are already present when crossing is used. Calf male proportion was positively
associated with increased MO-RA for CA0D2D, BECR-CA3D1M but negatively for heifers, suggesting that heifer
management is improved when availability of newborn heifers is decreased. Crossed-breed proportion was negatively
associated with MO-RA for all categories, when significant, suggesting more awareness and nursering for crossed
calves. First calving cow proportion was associated positively with MO-RA for CA0D2D and BECR-CA3D1M, but
negatively for all others (as previously reported for cow mortality).
Lung auscultation recordings and sonographic images from normal cattle and
those with respiratory tract pathology
P. SCOTT - University of Edinburgh, UK
[email protected]
Increased audibility of normal lung sounds can occur caused by hyperventilation after exercise and during hot weather.
Tachypnoea is common in toxaemic and septicaemic conditions but there may be no adventitious sounds. Moderate to
coarse crackles are identified in some cattle with chronic suppurative pneumonia but auscultation findings do not
correspond well to the distribution of superficial lesion(s) revealed during ultrasonographic examination, and at
necropsy. Auscultation does not detect pleural abscesses (up to 10 cm diameter). Marked attenuation of normal lung
sounds results from marked fibrinous pleurisy and extensive unilateral pyothorax. Pleural frictions rubs are not heard in
cases of pleurisy associated with CSPD and pleural abscesses. Rumen contraction sounds are often superimposed upon
lung sounds. Auscultation of the bovine chest alone does not allow the clinician to determine the presence of all
superficial lung pathology nor accurately define its distribution. Ultrasonography provides more accurate information
regarding the nature and extent of superficial lung pathology in cattle.
Typical examples of sound recordings and sonographic images will be presented.
BRSV- infections in Norwegian dairy cattle
T.B. KLEM - Norwegian School of Veterinary Science, Oslo, Norway
[email protected]
M. STOKSTAD - Norwegian School of Veterinary Science, Oslo, Norway
S.M. GULLIKSEN, O. OSTERAAS - TINE Norwegian Dairies, Aas, Norway
Respiratory disease is one of the most important diseases in the cattle industry, and it has a significant impact on both
animal welfare and the farmer’s economy. Bovine respiratory syncytial virus (BRSV) is a respiratory virus of
importance worldwide, and is commonly associated with clinical disease. The aim of this study was to increase the
knowledge of dynamics of BRSV infections in the Norwegian dairy cattle population.
The study was designed as a longitudinal, cross sectional study with random sampling stratified at herd level. 135 herds
were selected from 30 veterinary districts throughout the country. Blood samples were collected on two occasions in
each herd, with an interval of six months. Approximately five calves were included at each occasion, making a total of
approximately ten samples from ten individual calves collected in each herd. In addition, collection of bulk milk was
accomplished in 48 of the selected herds.
Serum and bulk milk samples were analyzed by use of a commercial ELISA kit for the presence of antibodies against
BRSV. The herds were then classified according to the number of calves that tested positive for antibodies. Herds with
at least one antibody-positive calf were regarded as newly infected, with circulation of BRSV in the herd during the last
year.
The overall results showed that BRSV is a relatively common infection in Norway, with widespread distribution. The
overall prevalence is lower than reported from many other countries throughout the world. The dynamics of BRSV as
evaluated by comparing results from the first and second sampling in each herd will be presented. Both within herd and
between herd dynamics will be discussed in the context of differences in topography of geographical areas, seasonal
variation and population density. The results of the bulk milk samples compared with the serology showed that bulk
milk as an indicator for circulating BRSV infection has very low sensitivity, but high specificity. Hence it does not
seem suitable for detection of herds with BRSV-infection, but suitable for correct classification of negative herds. This
knowledge will be useful in order to develop effective strategies to limit the spreading of BRSV.
Genetic loci associated with digital dermatitis in UK Holsteins
R. BLOWEY - Wood Veterinary Group, Gloucester, UK
[email protected]
R. SCHOLEY, S. CARTER - University of Liverpool, UK
It is well known that within any herd some cows are recurrently and often severely affected by digital dermatitis (DD),
whereas others in the same environment rarely if ever, show lesions. This suggests an underlying genetic susceptibility.
Using a candidate gene approach we investigated variations in the DNA known as single nucleotide polymorphisms
(SNPs), in key genes with immune function.
Three herds were scored monthly for DD over approximately 5 months of the autumn/winter in herring bone milking
parlours. Cows were then selected on the basis of those that always had DD and those that never had DD. Bloods were
taken to extract DNA for the genomic study.
In the initial study 23 DD cases and 24 controls were examined. Samples were processed using the Illumina chip which
has the capacity to identify 54,000 bovine SNP’s (single nucleotide polymorphisms). SNP’s are loci on the DNA where
adenine is replaced by thyamine in the complimentary strand, or where guanine is replaced by cytosine. 81 candidate
SNP’s were identified, many at loci towards the end of chromosome 26, at sites between 41 and 49MB (mega bases).
A larger sample was then processed, comprising 68 DD cases and 92 controls, then 68 cases and 174 controls.
Significant differences in the alleles of case versus control cows were found, especially in chromosome 26. One of these
was associated with HtrA1 (heat temperature requirement protein A1), the gene associated with inflammatory
processes, and a second with ANAPC (Anaphase promoting complex), the gene associated with cessation of mitosis.
Sub-acute ruminal acidosis: what to do ‘in the field’
M. DOHERTY - School of Veterinary Sciences, University College Dublin, Ireland
[email protected]
Introduction
There have been a number of comprehensive reviews of the literature on the subject of bovine sub-acute ruminal
acidosis (SARA) (Kleen et al., 2003; Enemark, 2008). It is broadly accepted that SARA is a common phenomenon with
a reported prevalence of 19% in early lactation and 26% in mid-lactation dairy cows in the USA. Australian and Irish
studies recorded a prevalence of between 10% and 15% in dairy cows grazing perennial ryegrass-based pastures
(Bramley et al., 2008; O’Grady et al., 2008) which were attributed to high concentrations of rapidly fermentable
carbohydrates and low levels of physically effective fibre in lush pastures.
Factors related to the development of low rumen pH are total dry matter intake (DMI), sorting of TMR feeds, irregular
feeding patterns, feeding forage and concentrate separately (Oetzel, 2005), meal size (component feeding versus TMR),
feed particle size, dietary fibre and starch concentrations (Nordlund, 2003; Nordlund et al., 1995) identified two
production groups in dairy herds at greatest risk of SARA. These are early lactation cows (within the first 3 weeks after
calving) and cows at peak DMI (10-14 weeks post calving). Early lactation cows are at higher risk due to a reduced
absorptive capacity of the rumen epithelium, poorly adapted rumen microflora, and the rapid introduction to highenergy dense diets. Cows at peak DMI are at risk due to the high levels of volatile fatty acids produced by microbial
fermentation, which overwhelm the buffering and absorptive capacity of the rumen. Oetzel (2005) reported a higher
prevalence of SARA in cows 80-150 days in milk than for cows of <80 days in milk for total mixed ration fed herds.
With regards the title of this paper, veterinary practice ‘in the field’ should whenever possible be based on evidence.
Therefore, I hope to focus on a number of questions and whilst doing so attempt to reflect on what might be considered
some of the uncertain or even controversial aspects of the phenomenon known as SARA.
These questions posed are as follows:
1.
2.
3.
4.
5.
What is SARA and is there a consensus opinion around its definition?
What are the clinical and sub-clinical sequelae to SARA?
What is the evidence for links between SARA and laminitis?
How is SARA diagnosed ‘in the field’?
How is SARA monitored and controlled?
What is SARA and is there a consensus opinion around its definition?
Unfortunately, there appears to be no consensus opinion around the definition of SARA in the literature. The confusion
is compounded by an overly liberal use of adjectives describing ruminal acidosis as well as with a propensity to use
inappropriate synonyms. The Saunders Comprehensive Veterinary Dictionary (Blood et al., 2007) describes acute as
"having severe signs and a short course of 12-24 hours", sub-acute as "between acute and chronic of the order of a
week’s duration", chronic as "persisting for a long time". It is unfortunate that the idea of disease severity is only
alluded to in the definition of acute while disease duration is referred to in the three definitions. Blood et al. (2007)
provide a definition of subclinical as "without clinical manifestations, of the early stages or a very mild form of a
disease".
Under "sub-acute ruminal acidosis", the Merck Veterinary Annual (2010) fails to provide clarification by giving
"chronic ruminal acidosis and subclinical ruminal acidosis as synonyms for SARA". Radostits et al. (2007) define
SARA as "repeated bouts of depressed rumen pH between 5.2 and 5.6" but do not detail the duration of the bouts of
lowered pH. A comprehensive review on the monitoring, prevention and treatment of SARA by Enemark (2008) begins
with the sentence "Sub-acute ruminal acidosis (SARA), also known as chronic acidosis or sub-clinical acidosis" further
underlining the confusion around definition and terminology. There is also no agreement on the pH threshold associated
with SARA. Krause & Oetzel (2006) defined SARA as periods of moderately depressed ruminal pH (5.5 to 5.0). Those
authors were critical of the use of terms chronic or subclinical stating that SARA is associated with short episodes of
lowered pH between calving and 5 months after calving. Gozho et al. (2005), Plaizier et al. (2008) proposed a specific
definition of SARA, which addressed both severity (pH 5.2-5.6) and duration (>174-180 minutes/day).
As clinicians, we need to be consistent in the use of descriptive terminology. We also need to be clear on what exactly
on what SARA is and perhaps, more importantly what it isn’t. In the latter context, it is important to clearly distinguish
SARA from acute ruminal lactic acidosis because examination of the literature, particularly in relation to the clinical
and subclinical sequelae of SARA, serves up a good deal of confusion. (Stone, 2004) defined acute ruminal acidosis as
a condition in which the ruminal pH is less than 5.0 to 5.2, while SARA was defined as a ruminal pH of approximately
5.2 to 5.6. Acute ruminal acidosis has been classically associated with grain overload resulting in a dramatic fall in
rumen pH to 5.2 or less as lactic acid-producing bacteria, produce large amounts of lactic acid (Nocek, 1997).
Importantly, the depression of ruminal pH in dairy cows with SARA is predominantly due to the accumulation of
volatile short-chain fatty acids (SCFA) mainly acetate, proprionate and butyrate and not due to lactic acid production
(Oetzel et al., 1995; Goff, 2006); the significance of the accumulation of N-valerate in SARA remains uncertain
(Morgante et al., 2007). This is a fundamental point of differentiation between acute ruminal acidosis and SARA but
unfortunately on many occasions the literature fails to address this.
In conclusion, we need to be accurate in our use of terminology and definition and agree that SARA is a transient
phenomenon defined by degree (pH 5.2-5.6) and duration (>180 minutes) (Gozho et al., 2005) . This immediately
highlights the challenge of field diagnosis, which unfortunately because of practical considerations is often only a
single-point prevalence measurement of degree but not duration.
What are the clinical and sub-clinical sequelae?
SARA in dairy cows has been implicated in the aetiology of laminitis (Oetzel, 2000; Enemark et al., 2002), decreased
dry matter intake (DMI) (Garrett, 1996), poor body condition score (Oetzel, 2000), loose faecal consistency (Nordlund
et al., 1995; Oetzel, 2000), low milk fat syndrome (Nordlund et al., 1995; Oetzel, 2000), caudal vena cava syndrome
(Nordlund et al., 1995) and abomasal displacement/ulceration (Olson, 1991).
However despite this, in the opinion of the author, the links between SARA as defined accurately by (Plaizier et al.,
2008) and clinical sequelae in particular are far from clear. The evidence that rumenitis is a fundamental lesion in
SARA is lacking and there has been a confusing tendency in the literature when discussing SARA to fail to adequately
differentiate it from acute ruminal lactic acidosis, frequently based on beef feedlot grain models (Szemeredy & Raul,
1978; Nocek et al., 1984) described many years before the phenomenon of SARA in dairy cows was adequately
described. Goff (2006) also raised this concern by stressing that the aetiology of SARA was quite different from
classical description of acute ruminal acidosis in beef feedlot cattle. In acute ruminal acidosis there is a rapid production
of lactic acid following a sudden change to a high starch diet, destroying rumen microbes and releasing endotoxin into
the blood; severe metabolic acidosis and death may ensue; the development of abscesses in the liver and related caudal
vena caval thrombosis are also potential clinical sequelae. As stated previously, lactic acid production is not a
significant characteristic of SARA in dairy cows and unlike this severe acute picture of acute ruminal acidosis, the
evidence for clinical sequelae to what is a subtle and relatively short-lived disruption of the rumen microenvironment is
lacking.
Key to our understanding of the issue of clinical sequelae is the inter-relationship of the rumen microenvironment,
peripheral blood and tissues remote from the rumen and in particular the corium of the bovine digits. The concept of the
"rumen barrier" and whether SARA as defined can induce significant local inflammation resulting in impaired ruminal
epithelial barrier function allowing translocation of toxins and bacteria to the liver and beyond is fundamental to this
discussion. References to development of parakeratosis and inflammation of the ruminal epithelium leading to
microabscesses in the ruminal mucosa were based on a beef feedlot model (Szemeredy & Raul, 1978) and there is no
convincing evidence of histopathologically detectable ruminal inflammation in SARA. Nocek et al. (1984) described
morphological changes of the ruminal epithelium in concentrate-fed bulls; these histological changes were characterised
by thicker/heavier epithelial lining, decreased papillary length, decreased number of papillary per field and decreased
absorptive capacity but no significant inflammatory component.
Steele et al. (2009) presented ultrastuctural evidence for ruminal epithelial disruption in a case report on one dairy cow.
However, the pH fall (<5.0) was consistent with a model of acute ruminal acidosis. Furthermore, recent research does
not support the hypothesis that SARA increases vascular permeability in the rumen. Penner et al. (2010) in a sheep
model, reported that a single, mild reduction of pH did not affect rumen barrier function and significantly. Furthermore,
(Gozho et al., 2007) showed that grain-induced SARA increased free LPS in the rumen but not in peripheral blood in
contrast to the hypothesis proposed by (Nocek, 1997).
At a subclinical level, there is evidence that the accumulation of SCFAs in ruminal fluid lowers pH resulting in
decreased feed efficiency by impairing fibre digestibility, a phenomenon associated the acid-sensitivity of the fibrolytic
rumen bacteria (Plaizier et al., 2008; Stone, 2004). Feed intake depression has been consistently linked to SARA (Kleen
et al., 2003; Plaizier et al., 2008) presented the hypothesis that the reduction in feed intake associated with SARA may
be due to an acute phase inflammatory response.
O'Grady et al. (2008) performed a point prevalence survey of rumen health status in grazing Irish dairy cattle fed
predominantly perennial rye grass-based pasture. The survey assessed rumen fluid, animal health status, milk
production data and pasture composition. Eleven percent of cows were classified as affected with SARA (pH <5.5),
42% were marginal (pH 5.6-5.8) and 47% were normal (pH>5.8). While the study showed that low rumen pH was
prevalent in grazing Irish dairy cattle consuming perennial rye grass-based pasture and raised concerns regarding
effective pasture utilization, it did not identify any statistical correlation with problems regarding animal health or
reduced animal performance.
Links between SARA and milk fat depression are inconsistent in the literature. Gozho et al. (2007) failed to
demonstrate any changes in milk fat due to grain-induced SARA while Griinari et al. (1998) reported that a low ruminal
pH results in increases in the trans-10 isomer of trans-octadecenoic acid that causes milk fat suppression.
Enemark (2008) suggested a strong physiological association between SARA and immunosuppression stating that ‘the
metabolic acidosis that results from SARA may result in reduced glucose-dependent insulin secretion, increased cortisol
secretion, reduced phagocytic activity and migratory speed of neutrophils’. However, evidence for systemic metabolic
acidosis resulting from SARA is also unconvincing and also appears to be based on an extrapolation from models of
acute and chronic lactic ruminal acidosis (Nocek, 1996; Brown et al., 2002).
What is the evidence for links between sara and laminitis?
Nocek (1997) is the most widely cited paper in the literature in the context of linking SARA with laminitis. However,
while this paper provides a very elegant description of the pathogenesis of bovine laminitis it fails to provide
convincing evidence for a link with ruminal acidosis. The paper places particular emphasis on a role for histamine
produced in the rumen based on limited evidence (Maclean, 1970) and confusingly states that in chronic laminitis
elevation of serum histamine might also be due to its release from inflammatory changes in the corium itself and from
anaerobic bacterial growth in developing foot abscesses. Nocek (1997) also postulated a role for bacterial endotoxin
(LPS) in initiating laminitis. However, very few studies have actually shown that SARA or even acute ruminal acidosis
increase LPS in peripheral blood. (Khafipour et al., 2009) reported that a grain-based model of SARA caused
translocation of LPS and triggered inflammation. However, the data suggested that the LPS release originated from the
terminal ileum and large intestine possibly due to bypassed starch. This introduces the intriguing hypothesis that the
large intestine, in addition to or independently of the rumen may be a source of translocating LPS.
Donovan et al. (2004) emphasized the dearth of research on the relationship between periparturient dairy cow diets and
hemorrhages of the sole. They commented that with the exception of work by Peterse (1982), controlled studies
demonstrating the influence of nutrition on sub-clinical laminitis had not been conducted. In a study, which involved a
range of diets commonly fed to dairy cows in Florida, they were unable to demonstrate a direct relationship between
ruminal acidosis and sub-clinical laminitis.
In the context of lameness and SARA, a key message relates to the relative impact of the cow’s environment and the
cow’s diet on the development of laminitis. One is always wary in veterinary science of the "mutually exclusive
hypotheses" and our current understanding of laminitis in the dairy cow is based on its multi-factorial nature but with a
consensus emerging that the cow’s environment is the final determinant of the degree of laminitis and lameness
experienced (Cook et al., 2004). It is significant that the European Food Safety Authority expert opinion report (EFSA
Journal, 2009) on lameness in dairy cows concurs with this view concluding as follows "the probability of risks
attributable to nutrition and feeding systems are low relative to those attributable to housing and management".
How is SARA diagnosed "in the field"?
In the field, the diagnosis of SARA remains problematical due to a combination of factors, including questions over the
validity of rumen pH measurements and uncertainty regarding potential clinical manifestations of SARA, which would
ensue several weeks after the initial insult. A rumenocentesis technique has been well developed in the USA and
significant work has been done on the appropriate interpretation of herd-level data. Other advances in the diagnosis of
SARA include developments in technology leading to the use of in-dwelling rumen wireless pH probes, the use of
rumen valerate and urinary net acid base excretion (Enemark, 2008). However, it is likely that diagnosis of SARA at
herd-level will continue to be based on a thorough herd investigation that takes cognisance of the inherent diagnostic
difficulties (Mulligan & Doherty, 2008).
Nordlund & Garret (1994) described rumenocentesis as a technique for consistently sampling rumen pH on-farm.
Duffield et al. (2004) demonstrated that samples collected by rumenocentesis correlated well with actual rumen pH in
comparison to samples collected via oral stomach tube as the buffering effect of saliva was avoided. Because of the
daily fluctuations in pH, Nordlund & Garret (1994) recommended sampling cows at 2-5 h after component feeding or 58 h after introduction to TMR to detect the daily nadir in ruminal pH. Oetzel (2003) suggested the sampling of 12 cows
at risk with a positive herd diagnosis if 3 or more have a rumen pH of less than 5.5.
Rumenocentesis can be easily conducted as described by Nordlund & Garrett (1994) using a needle from a 14-gauge, 80
mm long, intravenous catheter and a 20 mL syringe. The rumen fluid pH must be measured immediately on farm using
a calibrated electronic pH meter. Sedation is not required and no significant complications were reported by Morgante
et al. (2007) or O'Grady et al. (2008) during or after performing rumenocentesis.
AlZahal et al. (2008) reported that ruminal temperature might aid the detection of SARA and that rumen pH nadir was
negatively correlated with rumen temperature. The use of ruminal temperature to diagnose SARA in the field will
depend on the development of cost-effective intra-ruminal wireless telemetry temperature sensing devices.
How might SARA be monitored and controlled?
Several practical criteria that may be useful for monitoring rumen health on dairy farms when used collectively are
presented in Table 1.
Table 1: Selected monitoring criteria for rumen health (Mulligan et al., 2006)
Rumination
% of resting cows ruminating
Chews per bolus in resting cows
Erratic feed intake: yes/no
Faecal consistency score
Faecal sieve test
Milk fat depression mid-lactation animals
Groups
Individual
% concentrates in diet
% cereals in concentrate
% diet starch and sugars
Dietary fibre table
Crude fibre
ADF
NDF
NDF from forage
% forage length >13 mm
% forage length >40 mm
Long fibre in the ration
Component fed herds
Kg of concentrate fed at milking
Rate of increase in concentrates after calving
Feed space available per animal
Targets
Reference
>80%
70
No
3
All particles < 0.5 cm
Chamberlain & Wilkinson (2002)
<10% animals milk fat
Milk protein % - fat % < 0.4%
<65%
#40%
<20-25%
Oetzel (2000) & Cook et al., (2005)
15-17%
19-21%
27-30%
21-22%
30%
5-10%
1-2 kg
#6 kg
#0.75 kg/day
0.6 m
Oetzel (2005)
Zaaijer & Noordhuizen (2003)
Kleen et al., (2003)
Shaver (1993)
Shaver (1993)
Grant & Albright (1995)
Milk fat percentage in early lactation cows is of no diagnostic value in SARA and the frequency of recording is crucial
as the milk fat test should be performed weekly if possible. Allen (1997) summarised data from several trials
demonstrating a weak relationship between milk fat percentage and ruminal pH, while Garrett (1996) showed poor
correlation between milk fat percentage and the presence of SARA on farm. However, Cook et al. (2005) suggested if
10% of cows in a herd have a milk fat percentage of #2.5%, then SARA may be suspected. Faecal consistency/fibre and
rumen fill have also been suggested as cow level assessments of fibre within the diet and rumen function (Zaaijer &
Noordhuizen, 2003; Garry, 2002). The detailed fatty acid profile of milk may offer promise as a diagnostic tool as there
is some evidence that low rumen pH changes the biohydrogenation of unsaturated fatty acids (Plazier, personal
communication).
Stone (2004) in the context of dietary prevention of SARA, stressed the importance of physically effective neutral
detergent fibre provided by ration ingredients, along with their expected ruminal fermentabilities and resultant microbial
acid production. Environmental conditions, such as poor cow comfort which may alter feed intake patterns and animal
behaviour, should also be considered in ration formulation.
Conclusions
Sub-acute ruminal acidosis (SARA) is a phenomenon that poses particular diagnostic challenges. There is a need to
adhere to agreed clear and concise definitions of this condition specifying degree and duration. Further research will be
necessary to allow a better understanding of SARA and any potential clinical sequelae; this will include molecular
studies on the complexity of the rumen microbiome and the dynamics of changes in this microbiological environment in
response to a lowering of pH (Krause, 2010).
References
Allen MS - Relationship between fermentation acid production in the rumen and the requirement for physically
effective fiber. J Dairy Sci, 1997, 8:1447-1462.
AlZahal OE et al. - Ruminal temperature may aid in the detection of subacute ruminal acidosis. J Dairy Sci, 2008,
91(1):202-207.
Blood DC, Studdert VP, Gay CC - Saunders Comprehensive Veterinary Dictionary, 2007, Saunders, London.
Bramley E et al. - The Definition of Acidosis in Dairy Herds Predominantly Fed on Pasture and Concentrates1. J Dairy
Sci, 2008, 91(1):308-321.
Chamberlain AT, Wilkinson JM - Feeding the Dairy Cow. 2002, Chalcombe Publications, Lincoln, UK.
Cook NB et al. - Clinical forum - sub-acute ruminal acidosis - a problem in UK dairy herds? UK Vet, 2004, 10 (2):4046.
Cook NB et al. - Environmental Influences on claw horn lesions associated with laminitis and sub-acute ruminal
acidosis (SARA) in dairy cows, J. Dairy Sci, 2004, 87 (E. Suppl):E36-E46.
Donovan GC et al. - Influence of Transition Diets on Occurrence of Subclinical Laminitis in Holstein Dairy Cows. J
Dairy Sci, 2004, 87(1):73-84.
Duffield TF et al. - Comparison of techniques for measurement of rumen pH in lactating dairy cows. J. Dairy Sci, 2004,
87:59-66.
EFSA Journal (2009) 1142, 1-57 - Scientific opinion on welfare of dairy cows in relation to leg and locomotion
problems based on a risk assessment with special reference to the impact of housing, feeding, management and genetic
selection.
Enemark J - The monitoring, prevention and treatment of sub-acute ruminal acidosis (SARA): A review. Vet J, 2008,
176(1):32-43.
Enemark JMD, Jørgensen RJ, Enemark PS - Rumen acidosis with special emphasis on diagnostic aspects of subclinical
rumen acidosis: a review. Veterinarija Ir Zootechnika, 2002, 20:16-29.
Garrett E - Subacute rumen acidosis. Clinical signs and diagnosis in dairy herds. Large Animal Veterinarian, 1996,
11:6-10.
Garry FB - Indigestion in ruminants. In: Smith, B.P. (Ed.), Large Animal Internal Medicine, 3rd ed. Mosby, St. Louis,
2002 :722-747.
Goff JP - Major Advances in Our Understanding of Nutritional Influences on Bovine Health, J Dairy Sci, 2006,
89:1292-1301.
Gozho G al. - Ruminal lipopolysaccharide concentration and inflammatory response during grain-induced subacute
ruminal acidosis in dairy cows. J Dairy Sci, 2007, 90(2):856-866.
Gozho G al. - Subacute ruminal acidosis induces ruminal lipopolysaccharide endotoxin release and triggers an
inflammatory response. J Dairy Sci, 2005, 88(4):1399-1403.
Grant RJ, Albright JL - Feeding behaviour and management factors during the transition period in dairy cattle. J Anim
Sci, 1995, 73:2791-2803.
Khafipour E et al. - A grain-based subacute ruminal acidosis challenge causes translocation of lipopolysaccharide and
triggers inflammation. J Dairy Sci, 2009, 92(3):1060-1070.
Kleen J et al. - Subacute ruminal acidosis (SARA): a review. J Vet Med, 2003, Series A 50(8):406-414.
Krause D - Proceedings of 14th International Conference on Production Diseases of Farm Animals, 2010, University of
Ghent.
Krause KM, Oetzel GR - Understanding and preventing subacute ruminal acidosis in dairy herds: A review. Anim Feed
Sci and Tech, 2006, 126(3-4):215-236.
Merck Veterinary Manual - 2010 10th Edition, Merck & Co. Inc.
Morgante MC et al. - Subacute rumen acidosis in lactating cows: an investigation in intensive Italian dairy herds. J
Anim Phys and Anim Nutr, 2007, 91(5 6):226-234.
Mulligan FJ, Doherty ML - Production diseases of the transition cow. Vet J, 2008, 176(1):3-9.
Mulligan FJ et al. - A herd health approach to dairy cow nutrition and production diseases of the transition cow. Anim
Repro Sci, 2006, 96(3-4):331-353.
Nocek JE - Bovine acidosis: implications on laminitis. J Dairy Sci, 1997, 80(5):1005-1028.
Nocek JE, Heald CW, Polan CE - Influence of ration of physical form and nitrogen availability on ruminal morphology
of growing bull calves. J Dairy Sci,1984, 67:334.
Nordlund KV - Herd-based diagnosis of subacute ruminal acidosis. Preconvention seminar 7: dairy herd problem
investigation strategies. In: Proceedings of the 36th Annual Conference of the American Association of Bovine
Practitioners, 2003, Columbus, OH, USA.
Nordlund KV, Garrett EF, Oetzel GR - Herd based rumenocentesis: a clinical approach to the diagnosis of subacute
rumen acidosis. Compendium on Continuing Education for the Practicing Veterinarian: Food Anim, 1995, 17:S48-S56.
Oetzel GR - Applied aspects of ruminal acidosis induction and prevention. J Dairy Sci, 2005, 88 (Suppl. 1), 643.
Oetzel GR - Clinical aspects of ruminal acidosis in dairy cattle. In: Proceedings of the 33rd Annual Meeting of the
American Association of Bovine Practitioners, vol. 33, Rapid City, SD, 2000:46-53.
Oetzel GR - Herd-based biological testing for metabolic disorders preconvention seminar 7: dairy herd problem
investigation strategies. In: Proceedings of the 36th AABP Annual Conference, 2003.
Oetzel GR - Monitoring and testing dairy herds for metabolic disease. Vet Clin Food Anim Pract, 2004:20
O'Grady L et al. - Subacute ruminal acidosis (SARA) in grazing Irish dairy cows. Vet J, 2008, 176(1):44-49.
Olson JD - Relationship of nutrition to abomasal displacement and parturient paresis. Bov Pract, 1991, 26:88-91.
Penner G et al. - A single mild episode of subacute ruminal acidosis does not affect ruminal barrier function in the short
term. J Dairy Sci, 2010, 93(10):4838-4845.
Plaizier J et al. - Subacute ruminal acidosis in dairy cows: The physiological causes, incidence and consequences. Vet J,
2008, 176(1):21-31.
Stone W - Nutritional approaches to minimize subacute ruminal acidosis and laminitis in dairy cattle. J Dairy Sci, 2004,
87:E13-E26.
Zaaijer D, Noordhuizen JPTM - A novel scoring system for monitoring the relationship between nutritional efficiency
and fertility in dairy cows. Irish Vet J, 2003, 56 (3):145-156.
Effect of dietary potassium content and anionic salts
on the mineral balance in periparturient dairy cows
M. RERAT - Agroscope Liebefeld-Posieux Research Station ALP, Posieux, Switzerland
[email protected]
P. SCHLEGEL - Agroscope Liebefeld-Posieux Research Station ALP, Posieux, Switzerland
In Switzerland, native K concentrations in herbage are high. Dry cow diets largely based on these fresh or conserved
forages have high dietary K concentrations and could be responsible for the reduced ability to maintain Ca homeostasis.
The aim of this study was to determine whether the supplementation of anionic salts to a forage-based diet varying in
native K concentrations would affect the mineral balance in transition cows.
Twenty four primiparous and multiparous Holstein cows, without antecedent episodes of clinical hypocalcemia were
assigned to four different diets during the last 4 weeks before the estimated calving day.
Twelve cows were fed a restrictive diet based on a low-K hay (16 g K / kg DM; diet K16) and 12 cows a restrictive diet
based on high-K hay (32 g K / kg DM; diet K32). Within each diet, 6 cows received calcium sulfate salt (group K16AN
and K32AN) during the last 2 weeks before the estimated calving day.
After calving all cows were fed the same diet based on hay K32 ad libitum. Blood samples were taken daily for the
analysis of Ca, P and Mg from day 11 prepartum to day 5 postpartum. Urine samples were taken on day 7 and 2 before
parturition for the measurement of pH and the analysis of Ca, P, Mg, and creatinine. The dietary cation-anion balance of
diets K16, K16AN, K32 and K32AN was +258, +23, +505 and +252 mEq / kg DM, respectively. Lower dietary K level
had a positive effect (P<0.05) on the postpartum increase of plasma P. Plasma Ca was not influenced by the
experimental treatments. In group K16AN, the ratio of urinary Ca:creatinine was higher (P<0.01) and the pH lower
(P<0.01) than in the other groups.
The data indicates that:
• limiting dietary cations improved plasma P during the early postpartum period and,
• supplementing a low-K diet with anionic salts permitted to induce a mild metabolic acidosis as indicated by the
reduced urine pH and higher Ca excretion.
However this did not improve plasma Ca during the postpartum period.
Long-term measurement of rumen pH in dairy cows by an indwelling
and wireless data transmitting unit
J. GASTEINER - Federal Agricultural Research and Education Centre Raumberg-Gumpenstein, Irdning, Austria
[email protected]
J. LÜBBO KLEEN - CowConsult, Uplengen, Germany
T. GUGGENBERGER - Federal Agricultural Research and Education Centre Raumberg-Gumpenstein, Irdning, Austria
Subacute rumen acidosis (SARA) is a significant production disease of dairy cattle. The objective of this study was the
continuous and long term measurement of the ruminal pH in high yielding dairy cows under practical conditions.
Therefore, an indwelling system for monitoring ruminal pH and temperature, already described and evaluated by
Gasteiner et al. (2009), Veterinary Medicine Austria 96, 188-194, was applied on 4 dairy farms. Data were collected in
an internal memory chip and sent via radio transmission to an external receiver. The indwelling system was orally given
to 16 dairy cows out of 4 herds. Ruminal pH was measured every 600 sec over a period of 80 days starting 7 d prior to
calving date. Daily mean, nadir and time ruminal pH below 6.3; 6.0; 5.8 and 5.5 were calculated. Milk production,
feeding conditions and ration composition in terms of roughage and concentrate sources were determined and nutrient
components were known. Statistical analysis was conducted using GLM (Statgraphic Plus 5.1).
Radio transmission of data (twice daily) was functioning without any difficulties. Mean ruminal pH for all cows in all
herds was 6.6, ranging from pH 6.7 during dry period to pH 6.1 on day 80 of lactation. A significant decline of ruminal
pH was seen immediately after parturition, explainable by an increasing dry matter intake, and a second decline
occurred 25 to 30 days postpartum due to the increasing amount of fed concentrates. There was also a significant
relationship between roughage composition (ratio grass silage : corn silage ranging from 30:60 to 60:30) and ruminal
acid-base status. Ruminal pH continuously decreased from pH 6.8 to pH 6.4 with an increasing percentage of corn
silage in the ration.
Results were significantly influenced by the ration composition, by the day of lactation and by the milk yield, and show
that the presented method is a very useful and proper tool for both scientific and practical applications.
Herd audit for bovine parasitology:
an effective tool to customize anthelmintic treatments to the real risk
P. CAMUSET - Yvetot, France
[email protected]
In numerous areas in Europe, the utilization of anthelmintics is not based on epidemiologic investigations. That
situation induces an overuse of parasiticides, sometimes in an adverse way. Lack of efficacy and genesis of resistances
towards those molecules are risks commonly recognized.
It becomes necessary to reason the anthelmintic treatments to optimize the zootechnical performances of cattle herds at
competitive costs while, if possible, building up immunity toward parasites. That immunity allows us to reduce
progressively the use of anthelmintics on adult or nearly adult cattle.
To reach that aim, a herd audit methodology is proposed, based on an exhaustive determination and hierarchisation of
the parasitic dangers of each herd and their impact on the requested performances.
Commonly, that investigation needs two or three appointments (initially before turn out mainly in spring, then if
necessary in summer and eventually in autumn).
The visit before turn out is the longest and the most complete.
The first step of that process is a farmer interview concerning his preoccupations, the detailed pasture management and
the history of the parasitism management. The second step consists on a perfect understanding of the pasture
management, first for each pasture then for each generation. The understanding of the parasitic dynamic in the herd
affords to submit to the breeder a range of agronomic and medical tools perfectly tailored to his requirements.
Agronomic advisements are systematically addressed and used if possible. Medical tools are precisely selected to
ensure a balance between zootechnical performances and immunity.
Numerous laboratory investigations, following the example of a quality method, are performed to assess if necessary
the parasitic risk but also as efficacy criteria of the process set in motion.
That method, used in my practice since five years, has often led to a reduction of the utilization of anthelmintics and
systematically to an improvement of the health and the performances of the investigated herds.
The process and some examples will be explained.
Neonatal diarrhea: calves from vaccinated flocks against rotavirus, coronavirus
and E. coli excrete less of Cryptosporidium parvum
K. ADJOU - ENVA, Maisons-Alfort, France
[email protected]
D. BAROUDI, D. KHELEF - ENSV, Algiers, Algeria
A. MEGHRAOUI - UMR BIPAR, Maisons-Alfort, France
Cryptosporidium sp is a protozoan parasite of the digestive tract of many vertebrates domestic ruminants. The cycle
includes a parasitic phase during which the multiplication leads to intense emission in the faeces of infectious elements,
oocysts. Transmission occurs by direct contact through contaminated water or food. The disease results from infection
called cryptosporidiosis, is expressed by a digestive disease (enteritis) in ruminants.
Parasitological investigations were carried out in a mediterranean region to determine the prevalence of three
protozoans (Cryptosporidium, Giardia, Eimeria) in calves and to determine whether vaccination limits or discloses the
pathogenicity of Cryptosporidium, as has been reported in the litterature. Fresh faecal samples were collected from 454
calves in 29 farms in Algeria. Faeces were analyzed by the Ritchie’s method followed by the modified Ziehl-Neelsen
staining techniques. The %2 test is used for the statistical calculation.
Our results showed 47.79% positive cases for Cryptosporidium oocysts, 23.56% are positive for Giardia and 15.63%
for Eimeria. Associations of protozoans were observed, especially in the period of 25-45 days.
Animals from herds that vaccinate against the coronavirus, rotavirus, and E. coli excrete significantly less
Cryptosporidium than those not vaccinated. A paradox is highlighted here because it's classically admitted that
vaccination against "viruses and bacteria" is responsible for the high protozoan infection which have become a major
concern during the neonatal period in breedings. Indeed, excretion observed here in vaccinated calves remains
considerable. This underlines the pathogenicity of Cryptosporidium alone and this may also suspected vaccine failures.
Vaccination seems to have a limiting effect against Cryptosporidium. The three parasites are detected in the faeces or
not, stressing the importance of asymptomatic carriers. The association of Cryptosporidium and Giardia is clinically
significant %2 (P<0.05) in calves with diarrhea.
In conclusion, these data confirm the frequent occurrence of Cryptosporidium sp in calves in Algeria (47.79%) which
differs little from that found in other conditions. Other investigations are clearly needed to understand the relationship
between vaccination of calves against "viruses and bacteria" and the occurrence of cryptosporidiosis in cattle farms.
Emerging resistance to carbapenems in Gram negatives
recovered from dairy cows
Y. MILLEMANN - Université Paris-Est, Ecole Nationale Vétérinaire d’Alfort, Maisons Alfort, France
[email protected]
G. PANNAUX - Université Paris-Est, Ecole Nationale Vétérinaire d’Alfort, Maisons Alfort, France
P. NORDMANN, L. POIREL - INSERM U914 "Emerging Resistance to Antibiotics", Hôpital de Bicêtre, Faculté de Médecine ParisSud, Le Kremlin-Bicêtre, France
Resistance to antibiotics has been described in bacteria isolated from cattle. Emergence of Gram negatives exhibiting
resistance to 3rd generation cephalosporins by production of extended-spectrum ß-lactamases (ESBLs) in animal
isolates is particularly worrysome. In order to better evaluate the rate of resistance to broad-spectrum ß-lactams in
France, a study has been conducted in a dairy farm, aiming to evaluate the rate of colonisation by cephalosporinresistant Gram negatives.
The screening was performed by trans-rectal swabbing of 50 cows randomly chosen in 3 different dairy herds situated
in the Paris region. Screening was performed by using agar plates selecting for ESBL-producing isolates (ChromID
ESBL, bioMérieux, France), and Drigaslki plates containing 1 $g/ml of imipenem. Agar plates were incubated 18 hours
at 37°C after a pre-enrichment phase in LB broth. Bacterial species were then identified by routine biochemical testing,
and eventually by molecular tools (16S RNA or GyrA sequencing).
Samples collected from one farm gave nine Gram negatives resistant to carbapenems. They had been recovered from 9
different cows. None of these cows exhibited any clinical sign. No cow was treated with antibiotics at the moment of
sampling. The colonies were identified as Acinetobacter genomospecies 15TU, a species not responsible for cattle nor
human infections, but known to be present in the environment.
PCR and sequencing allowed identifying the same gene encoding the carbapenem-hydrolysing class D ß-lactamase
OXA-23. Interestingly, OXA-23 is known to be the main mechanism leading to resistance to carbapenems in
Acinetobacter baumannii in humans worldwide. All the isolates harboured the blaOXA-23 gene on their chromosome.
Surprisingly, pulsed field gel electrophoresis analysis identified six different clones out of the nine A. genomospecies
15TU isolates.
The study is currently in progress to possibly identify eventual risk factors that might have contributed to the selection
and emergence of such carbapenem-resistant Gram negatives. We demonstrated here that cows could be reservoirs of
resistance determinants that are clinically relevant in human medicine. To the best of our knowledge, that study
constitutes the first identification of carbapenemase acquisition in animals.
In conclusion, this description encourages the development of routine surveillance of resistant bacteria in herds,
including antibiotics that are not licensed for veterinary use but of high clinical relevance for humans.
News about mastitis-causing staphylococci
S. PYÖRÄLÄ - University of Helsinki, Faculty of Veterinary Medicine, Department of Production Animal Medicine,
Saarentaus, Finland
[email protected]
H. SIMOJOKI, S. TAPONEN - University of Helsinki, Faculty of Veterinary Medicine, Department of Production Animal Medicine,
Saarentaus, Finland
Introduction
Staphylococci are the most prevalent mastitis causing bacteria. Staphylococcus aureus (S. aureus) is still is the most
important mastitis pathogen in many countries. S. aureus mastitis can be clinical or subclinical, and considerably
increases milk somatic cell count (SCC). It easily spreads between cows, responds poorly to antimicrobial therapy and
often remains chronic. Coagulase-negative staphylococci (CNS), a group of staphylococcal species, have become
common as mastitis causing agents. CNS mastitis mostly remains subclinical, but may persist in the quarter for long
periods. CNS mastitis generally responds well to antibiotic therapy. CNS are in general more resistant to antimicrobials
than S. aureus. Some staphylococcal species can have zoonotic characteristics. In the following, recent trends and
developments on mastitis causing staphylococci and staphylococcal mastitis are reviewed.
Prevalence, epidemiology and ecology of staphylococcal mastitis
Prevalence of mastitis caused by S. aureus greatly varies from country to country. While a decreasing trend can be seen
in the prevalences of S. aureus mastitis in some countries, it still remains a major problem of the dairy industry. A
recent study from France, Rhône-Alpes, reported that the proportion of S. aureus among mastitis causing agents was
16% in clinical and 30% in subclinical mastitis (Botrel et al., 2010). In Finland, about 18% of clinical and 10-15% of
subclinical mastitis have been caused by S. aureus (Pitkälä et al., 2004; Koivula et al., 2007). In the Netherlands S.
aureus has been the most common pathogen, isolated in about 20% of quarters with subclinical infection, but its
prevalence has since decreased to less than 7% (Sampimon et al., 2010). In Brandenburg, Germany, S. aureus was
isolated in 6% of quarters with subclinical mastitis (Tenhagen et al., 2006), but in Belgium in 25% of culture-positive
milk samples (Piepers et al., 2007). In Swedish primiparous cows, S. aureus was the most commonly isolated bacterium
in clinical mastitis (Persson Waller et al., 2009).
CNS have become predominant pathogens isolated in subclinical bovine mastitis in many countries. In France, the
proportion of CNS among mastitis causing agents was 10% in clinical and 14% in subclinical mastitis (Botrel et al.,
2010). In a Finnish study comprising routine mastitis samples, approximately 16% of clinical and close to 30% of
subclinical mastitis were caused by CNS (Koivula et al., 2000). In the Netherlands, the prevalence of CNS infections
was estimated to be 11% at quarter level and 34% at cow level, making it the most frequently isolated group of
pathogens (Sampimon et al., 2009a). In Germany, 17-35% of quarters with subclinical mastitis harboured CNS
(Tenhagen et al., 2006; Schwarz et al., 2010). In Belgium, CNS have been predominant (41%) in quarters with
subclinical mastitis (Piepers et al., 2007).
Staphylococcal species have a very good genetic flexibility, which likely has promoted their adaptation to different
environments and hosts. S. aureus is a clonal organism as the populations consist of groups of genetically related strains
with a common ancestor (Ben Zakour et al., 2008). S. aureus strains originating from bovine mastitis mostly represent a
genetically different cluster than the human strains, indicating host-specificity (van Leeuwen et al., 2005; Herron-Olson
et al., 2007; Monecke et al., 2007; Alves et al., 2009). Transfer between hosts however takes place as identical S. aureus
strains have been isolated in dairy cows and people (Jørgensen et al., 2005; van den Borne et al., 2010a; Haenni et al.,
2011). Milk from infected quarters is considered to be the most important reservoir of S. aureus. Milking liners are
likely sources of S. aureus (Jørgensen et al., 2005; Hovinen et al 2010). S. aureus has been isolated on all external
surfaces of cows, but udder skin may be the preferred site (Jørgensen et al., 2005; Haveri et al., 2008). S. aureus is
frequently found on teat walls, teat orifices and teat canals of healthy quarters (Paduch & Krömker 2011). Other
common reservoirs are lesions on the hocks and other skin sites, but in the adult bovine not nostrils (Haveri et al., 2008;
Capurro et al., 2010b; Nyman et al., 2010; Olde Riekerink et al., 2010). S. aureus was more often isolated if the hock
had hair loss or skin lesions, and skin isolates were of the same pulsotypes as found in milk (Capurro et al., 2010b,
Nyman et al., 2010).
Usually a limited number of S. aureus strains causes mastitis in a given herd and one or a few strains predominate
(Sommerhäuser et al., 2003; Mørk et al., 2005; Anderson & Lyman 2006; Said et al., 2010; Capurro et al., 2010b). In
herds with efficient control of contagious mastitis, not any particular dominant S. aureus strain but several different
strains cause mastitis (Sommerhäuser et al., 2003; Graber et al., 2009). Spread from cow to cow of these strains seems
less likely and infections may be difficult to eradicate using routine measures.
At least 15 different CNS species have been isolated in mastitis (Pyörälä & Taponen, 2009). CNS species most
commonly isolated in mastitis are S. chromogenes, S. simulans, and S. epidermidis, and S. haemolyticus (Taponen et al.,
2006, 2009; Thorberg et al., 2009; Piessens et al., 2011). The distribution of CNS species causing intramammary
infections is herd-specific (Thorberg et al., 2009; Supre et al., 2011). S. simulans has been suggested to be a more
specific mammary pathogen than other CNS species; in one study on the ecology of CNS, S. simulans was mainly
detected in the milk of mastitic quarters, but only seldom in extramammary sites such as teat and udder skin, contrary to
other CNS species (Taponen et al., 2008). On the contrary, in a more recent study in 6 Belgian herds, S. simulans and S.
haemolyticus were found the environment, suggesting that these species were possibly of environmental origin
(Piessens et al., 2011). S. chromogenes and S. epidermidis were only rarely found in the environment. Herd-to-herd
differences in the distribution of CNS species were between most common isolation sites. Transfer of CNS between
humans and cows may happen as genetically related S. epidermidis were isolated in mastitis and in humans (Thorberg
2006; Jaglic et al., 2010). In humans, S. epidermidis and S. saprophyticus are the most common species (Piette
&Verschraegen, 2009). S. epidermidis isolated in bovine mastitis is suspected to mainly originate from human sources.
Prevalence of CNS mastitis is higher in primiparous cows than in older cows (Tenhagen et al., 2006; Taponen et al.,
2007; Sampimon et al., 2009a). S. chromogenes was the major CNS species in pre-calving heifers and primiparous
cows, whereas S. simulans or S. epidermidis was mostly isolated from older cows (Taponen et al., 2006; Thorberg et al.,
2009). Multiparous cows generally become infected with CNS in later lactation whereas primiparous cows are infected
already at the beginning of lactation (Gröhn et al., 2004; Taponen et al., 2007). The prevalence of CNS in cows and
heifers was higher in dairy farms with low bulk milk SCC (<150,000 cells/ml) than in dairy farms with medium or high
SCC (Sampimon et al., 2010). In a recent Belgian study in 20 herds, 80% of fresh heifers were infected by CNS at
parturition (Piepers et al., 2010).
Diagnostics
In clinical laboratories, combination of colony morphology, typical haemolysis and ability to coagulate rabbit plasma
are the commonly used criterions for the identification of S. aureus and CNS in cultures from milk samples. Rapid
agglutination tests have been used to replace conventional tube coagulase test (Boerlin et al., 2003). They are based on
simultaneous demonstration of protein A, clumping factor, and other surface antigens specific for S. aureus. The
performance of these tests is not satisfactory. In a recent study half of bovine S. aureus isolates failed to show a positive
result (Stutz et al., 2011). Detection of species-specific genes such as nuc or sequencing of the 16S rRNA gene can be
used for the identification of S. aureus, but these methods are not applicable in practical conditions.
In routine mastitis diagnostics, CNS are not identified to species level but treated as a uniform group. The commercial
phenotypic identification schemes are usually not designed to identify veterinary pathogens. They mostly fail to identify
all CNS strains of animal origin, possibly because of the limited number of veterinary strains in the databases (Zadoks
& Watts 2009). Some CNS isolates from bovine mastitis may not genetically belong to any documented Staphylococcus
species and new species have also been described (Taponen et al., 2006; Supré et al., 2010; Taponen et al., 2011).
Genotypic methods such as AFLP, ribotyping or detecting species-specific genes are recommended for identification of
bovine CNS (Zadoks & Watts 2009). A selection of different genes such as tuf or rpoB have been tested for diagnosis
of CNS (Mellmann et al., 2006; Capurro et al., 2009). A commercial, DNA-based mastitis test has recently come to
clinical use (PathoProof™ Mastitis PCR Assay, Thermo Scientific, Finland). This test can identify S. aureus and CNS
as a group, and it also detects blaZ gene coding for penicillin resistance (Koskinen et al., 2010). More knowledge about
the diversity and characteristics of different CNS species involved in bovine mastitis would be needed before
introduction of species-specific tests to identify different mastitis-causing CNS.
Virulence characteristics of staphylococci
S. aureus can produce different virulence factors during the course of infection and is able to cause many infections in
animals and humans. The early stage of infection is characterized by the production of proteins with tissue binding
properties to facilitate the attachment of bacteria to host tissues (Foster & Höök). The surface proteins of S. aureus bind
to fibrinogen, fibronectin and collagen (Furnier et al., 2008, Kerro-Dego et al., 2002, Stutz et al., 2011). S. aureus
adheres to bovine mammary epithelial cells better than most other bacterial species (Kerro-Dego et al., 2002; Hyvönen
et al., 2009). S. aureus can produce so-called MSCRAMM (Microbial Surface Components Recognizing Adhesive
Matrix Molecules) proteins, which are associated with adhesion and invasion of bacteria to the host cells (Foster and
Höök 1998). When infection is well established, the expression of tissue-binding proteins is down-regulated while
synthesis of extracellular toxins and tissue-degrading enzymes is induced to enhance acquisition of nutrients and spread
of infection (Mazmanian et al., 2003). To avoid the defence responses of the host S. aureus uses several strategies.
Protein A is an important surface protein of S. aureus, which binds immunoglobulin G: the incorrectly oriented IgG on
the bacterial surface then hides the bacterium from phagocytosis (Atkins et al., 2008). In addition to being resistant to
phagocytosis, staphylococci survive intracellularly in the phagosomes (Foster 2005). Most S. aureus isolates are
enclosed in a polysaccharide capsule which prevents the host cells to recognise the targets on bacterial surfaces (Foster
2005). S. aureus can express superantigens (enterotoxins) that interfere with the function of T and B cells of the host,
compromising the immunological memory (Haveri et al., 2007; Kozytska et al., 2010; Haenni et al., 2011).
The ability S. aureus to produce biofilm is well known (Stevens et al., 2009; Los et al., 2010). Biofilm protects bacteria
from the immune mechanisms of the host, as well as impairs phagocytosis. Biofilm also protects bacteria from
antimicrobial therapy (Cucarella et al.,, 2004; Melchior et al., 2006). Biofilm production of S. aureus and S. epidermidis
has been elevated by exposure to certain antibiotics (Rachid et al., 2000; Mitchell et al., 2010). Fox et al. (2005) showed
that biofilm formation was more common in S. aureus originating from milk than in S. aureus isolated from teat skin or
liners of the milking unit. Persistence of S. aureus infection may be related to the ability of the pathogen to transform to
slow growing, small colony variant, which survive intracellularly and efficiently escape from the defence mechanisms
of the host (Brouillette et al., 2003; Atalla et al., 2010; Tuchscherr et al., 2011). These variants are particularly resistant
to therapy. Characteristics of S. aureus isolated in mastitis vary, and so far not a single virulence factor has been
identified to be determinative in bovine mastitis (Herron-Olson et al., 2007; Kozytska et al., 2010; Stutz et al., 2011).
Compared with S. aureus much less is known about the virulence mechanisms of CNS. Differences among the CNS
species in the ability to persist in the udder or in pathogenity may exist. Surface characteristics such as hydrophobicity,
capsule and slime formation, adhesion to fibronectin and collagen, and several toxins and enzymes have been listed as
virulence factors of CNS (Zhang & Maddox, 2000; Almeida & Oliver, 2001; Seo et al., 2008). CNS can produce
superantigens (enterotoxins) (Park et al., 2011). S. epidermidis has a specific ability to form biofilms (Stevens et al.,
2008; Otto 2009; Piette and Verschraegen 2009). Bovine CNS have shown adhesive ability equal to that of S. aureus,
but internalisation varied among strains (Hyvönen et al., 2009). In a recent study, one third of mastitis isolates produced
biofilm when analyzed with phenotypic tests (Simojoki, unpublished). Slime forming ability was lower for S.
chromogenes and S. simulans than for S. epidermidis. Phenotypic biofilm formation was not associated with persistence
of infection or clinical signs of mastitis.
Studies comparing the pathogenic potential of different CNS species are few. CNS have been reported to cause clinical
mastitis (Taponen et al., 2006; Olde Riekerink et al., 2008; Gillespie et al., 2009), but in some studies they were isolated
only in subclinical mastitis (Supré et al., 2011). Infections caused by S. chromogenes, S. simulans or S. xylosus
increased SCC more than other CNS species (Supré et al., 2011). Many species can cause persistent infections, in
particular S. chromogenes (Taponen et al., 2006; Supré et al., 2011). In a Swedish study, persistent infections were
common in quarters infected with S. chromogenes, S. epidermidis, and S. simulans. In that study, no differences
between the CNS species in their association with milk production, milk somatic cell count, or month of lactation were
found (Thorberg et al., 2009). In a more recent Swedish study, S.epidermidis was significantly more prevalent in
subclinical than in clinical mastitis, while S. hyicus was significantly more common in clinical mastitis (Persson Waller
et al., 2011). Innate immune response of cows to CNS intramammary infections has been studied using experimental
infections with S. chromogenes, S. epidermidis and S. simulans (Simojoki et al., 2009, 2011). All cows became infected
and showed mild to moderate clinical signs of mastitis. The spontaneous elimination rate of the 16 infections by S.
epidermidis or S. simulans was 31.3%, with no difference between species. Infections triggered a local cytokine
response in the experimental udder quarters, but cytokines were not detected in the uninfected control quarters or in
systemic circulation. Local immune response for S. simulans was slightly stronger than that for S. epidermidis
(Simojoki et al., 2011).
Some studies have indicated that CNS mastitis could protect the quarter from other infections (Lam et al., 1996). On the
contrary, Parker et al. (2007) and Compton et al. (2007) showed that pre-calving intramammary infection with CNS in
heifers increased the risk for post-calving infection with CNS, S. aureus or Streptococcus uberis. In a recent study,
heifers infected with CNS had significantly lower risk for clinical mastitis (Piepers et al., 2010). CNS-infected cows had
a slightly elevated average SCC but a higher daily milk production than that of the non-infected herd mates. This could
be due to less clinical mastitis in them. Schukken et al. (2009) also reported that cows infected with CNS produced
slightly more than culture-negative cows and much more than cows infected with major pathogens. It has been
suggested that high-producing heifers could be more sensitive to CNS infections than low-producing heifers (Compton
et al., 2007).
Resistance for antimicrobials in mastitis-causing staphylococci
S. aureus have intrinsic susceptibility to most antimicrobials, beta-lactams included. Resistance to benzylpenicillin in S.
aureus is mediated by destruction of the drug by production of the enzyme beta-lactamase coded by the blaZ gene.
Resistance to benzylpenicillin is common among S. aureus. Generally one-third to two-thirds of bovine S. aureus
isolates have been resistant to penicillin (Hendriksen et al., 2008; Pitkälä et al., 2004; FinRes-Vet 2005-2006). Much
lower figures (2-7%) have been reported in Sweden and Norway, probably due to the very restricted antibiotic policies
in these countries (SVARM, 2008; NORM-VET 2005; Bengtsson et al., 2009). Plasmin-mediated penicillin resistance
can efficiently spread between animals and herds (Waage et al., 2002). Antibiotic resistance of S. aureus may have a
connection with some virulence factors: blaZ was often present together with enterotoxin genes sed and sej, indicating
presence of a penicillinase plasmid (Haveri et al., 2006, 2007). Resistance to oxytetracycline is another common form
of resistance in S. aureus (Pitkälä et al., 2004, Hendriksson et al., 2008; Bengtsson et al., 2009); in one study from Italy
it was as high as 60% (Moroni et al., 2006). Tetracycline should not be used in mastitis therapy as there is no evidence
of its clinical efficacy (Constable et al., 2008). Resistance to macrolides among mastitis-causing staphylococci has
generally been low in most countries. In a recent study in France, 1-4% of S. aureus and 2-14% of CNS were resistant
to erythromycin and spiramycin (Botrel et al., 2010). Previously up to 10% of mastitis-causing S. aureus in France were
reported resistant for macrolides (Hendriksen et al., 2008). Emerging resistance to macrolides and lincosamides would
be a concern as these drugs are commonly used in mastitis therapy.
S. aureus has developed resistance to methicillin (MRSA), coded by mecA gene (Catry et al., 2010). MRSA are
resistant to all beta-lactam antibiotics. They have been repeatedly isolated in bovine milk (Moon et al., 2007; Turutoglu
et al., 2009). In food animals, a new specific clone of MRSA (ST398) of unknown origin has emerged in pigs and later
also in cattle (Lewis et al., 2008; Olde Riekerink et al., 2010; Fessler et al., 2010). The first report on transmission of
MRSA between cows and humans was published in 2007 (Juhász-Kaszanyitzky et al., 2007). More recently, MRSA has
been isolated on several dairy farms in Germany and in Belgium (Fessler et al., 2010; Vanderhaeghen et al., 2010). In
Belgium, the proportion of MRSA was over 9% among S. aureus isolates from farms with mastitis problems. All
MRSA strains were resistant to tetracycline and in most cases also to macrolides, lincosamides and aminoglycosides. In
Germany, the food animal type of MRSA has been isolated in farm personnel. Human type MRSA has been detected in
bovine mastitis in France and Germany (Monecke et al., 2007; Haenni et al., 2011). It is likely that occasional MRSA
infections in dairy cows mostly originate from humans. However, MRSA-infected cows can spread the bacterium
further and are thus a human health hazard (Catry et al., 2010).
CNS isolated in mastitis are generally more resistant to antimicrobials than S. aureus and often develop multiresistance
(Pitkälä et al., 2004; van Duijkeren et al., 2004; Rajala-Schultz et al., 2009; Sawant et al., 2009; Sampimon et al., 2011).
Penicillin-resistance is less common than in S. aureus, and in general one fourth or third of CNS isolates are penicillinresistant. It is possibly species-linked, as it was more common in S. epidermidis and S. haemolyticus (about 40%), than
in S. simulans and S. chromogenes, of which none or only a few isolates were resistant (Persson Waller et al., 2011). In
Sweden, <10% of CNS were resistant to other antimicrobials than penicillin, which is again lower than reported in most
other countries (Persson Waller et al., 2011). Methicillin-resistance is in CNS more common than in S. aureus (Supré et
al., 2011), in particular in S. epidermidis (Fessler et al., 2010; Jaglic et al., 2010). However, it can be concluded that
methicillin resistance is generally still rare among mastitis-causing staphylococci.
Treatment of staphylococcal mastitis
Intramammary infections caused by S. aureus are often resistant to antimicrobial treatment (Barkema et al., 2006).
S. aureus causes a deep infection and the drug used should penetrate into the udder tissue (Erskine et al., 2003). In
clinical mastitis due to S. aureus systemic treatment may be more efficient, preferably in combination with
intramammary treatment (Constable et al., 2008). Increasing the duration of treatment improves cure rates in S. aureus
mastitis (Pyörälä & Pyörälä, 1998; Oliver et al., 2004; Deluyker et al., 2005). If the causing isolate is penicillinresistant, cure rates are very low, mostly <30% (Taponen et al., 2003; van den Borne et al., 2010a; Pyörälä et al., 2011).
Recently it was shown that when the mastitis-causing S. aureus strain was of human type, odds for cure was about 2.5
times as high as if the causing isolate was of bovine type, despite their penicillin-resistance (van den Borne et al.,
2010a). Treatment of subclinical S. aureus mastitis is seldom economical, but may be necessary in some situations for
decreasing infection pressure (Swinkels et al., 2005). Studies on treating cows based on high somatic cell counts have
generally shown no effect on milk production (Hallén Sandgren et al., 2008; van den Borne et al., 2010). Therapeutic
drying-off of the infected quarter during lactation is one measure used to manage chronic S. aureus infections, to stop
secretion of milk containing bacteria and thus to prevent spread between cows. No irritants should be infused into the
quarter during this procedure.
Spontaneous cure is common in intramammary infections of CNS, and antibiotic treatment of these infections is often
not considered necessary. Mastitis caused by CNS responds well to antimicrobial treatment, and bacteriological cure
has ranged from 80% to 90% (Pyörälä & Pyörälä 1998; Taponen et al., 2003a, 2006). As in S. aureus, penicillinresistance may affect cure rates also in CNS infections. Cure rates for mastitis caused by penicillin-resistant CNS have
been about 20% lower than those for mastitis caused by penicillin-sensitive CNS (Pyörälä & Pyörälä, 1998; Taponen et
al., 2006). Extending length of treatment is not necessary in CNS mastitis. Treatment for 8 days was no better than 2day treatment in subclinical CNS mastitis (Deluyker et al., 2005). In that study, the cure rate of CNS mastitis was 44%
without treatment. Intramammary antimicrobial treatment of quarters with persistent CNS mastitis can be
recommended. Antimicrobial treatment of cows infected by CNS at drying-off is also a good tool to control CNS
mastitis, as cure rates of dry cow therapy are generally very high for these infections (Newton et al., 2008).
Prevention of staphylococcal mastitis
For staphylococcal mastitis as for all mastitis, prevention is the key to combating the problem. The so-called 5-point
plan (NMC 1987) has been used to control mastitis caused by S. aureus, but it has not been as efficient as in mastitis
due to the specific udder pathogen Streptococcus agalactiae. Current control strategies of mastitis caused by S. aureus
include improved milking hygiene, maintaining good condition of teat and leg skin, segregation of the cows if
necessary, targeted treatment or culling of infected cows and use targeted treatment at drying-off. Teat dipping is
commonly used for prevention of S. aureus mastitis, but scientific evidence of its efficiency in field conditions is scant.
Most studies on the efficacy of teat dips are old and have been conducted in experimental conditions or herds (e.g.
Nickerson et al., 1986). In a Norwegian large scale field study, use of teat dip did not decrease S. aureus infections in
the studied herds (Whist et al., 2006).
The most effective strategies for prevention of CNS mastitis are still to be defined. Common control measures against
contagious mastitis pathogens may help. Some CNS species may be opportunists from the environment and need
specific attention. In most herds, pregnant heifers are more likely to be infected with CNS than cows, and in solving
CNS mastitis problems focus should be on the heifers. Risk factors have been related to feeding, housing and
management of heifers as well as udder oedema and leaking of milk (Fox 2009). An increased prevalence of CNS
infections have been associated with poor quality water, housing of dry cows and heifers together, lack of udder health
monitoring, and contamination of the stalls with milk (Sampimon et al., 2009b). Pre-partum intramammary antibiotic
therapy for heifers has been suggested for control of CNS mastitis. This practice has reduced the number of CNS
infections or clinical mastitis during first lactation, but the effect on SCC has been variable (Middleton et al., 2005;
Sampimon et al., 2009b). In a study of several herds from the US and Canada (Borm et al., 2006), no clear advantage of
prepartum antibiotic therapy of heifers was demonstrated. Control of CNS mastitis should not depend on routine use of
antibiotics to pre-partum heifers.
In a meta-analysis on the efficacy of dry cow treatment (Robert et al., 2006), no significant benefit was established
regarding the prevention of CNS infections with blanket dry cow therapy. Combined result of Staphylococcus spp.
(CNS and S. aureus) from dry cow therapy in another meta-analysis by Halasa et al (2009a) showed increased cure
from existing infections with dry cow therapy, but preventing new infections was not obvious (Halasa et al., 2009b).
Commercial vaccines are available in many countries for prevention of staphylococcal mastitis, but their efficacy is
limited (Pereira et al., 2011). S. aureus infection can trigger a strong immune response against many antigens, but
immunological memory remains short (Talbot and Lacasse, 2005; Ohlsen et al., 2010). In the EU, a mastitis vaccine
against E. coli and staphylococcal mastitis has recently been launched to the market (Startvac®, Laboratorios Hipra,
Spain), with an indication for prevention of staphylococcal and Escherichia coli mastitis and reducing clinical signs.
The product literature states that the vaccine should only be used as part of a mastitis control programme of a herd. This
vaccine has been tested in six Spanish herds in Spain with severe mastitis problem. In the study herds, the incidence of
mastitis was about 60%, treatment incidence over 50%, and the average bulk milk SCC over 500,000/ml. It is not
known if any benefit from this vaccine can be expected in herds with less mastitis. Independent scientific publications
on the efficacy of this vaccine are not yet available.
Conclusions
In mastitis diagnostics it is crucial to separate S. aureus and CNS. Commercial slide tests are not reliable for bovine
staphylococcal isolates and the conventional tube coagulase test is recommended. Another option is to use PCR-based
diagnostics. S. aureus has a clear clonality, and generally some strains predominate in herds. It is possible that these
strains possess some specific virulence factors which favour their ability to cause intramammary infections and reside in
the udder. In general, S. aureus is host-specific, but mastitis causing strains may also originate from humans. In the
future, strain-based diagnostics may be possible which would help in planning strategies for prevention. As now, no
practical tools are available for this. In an S. aureus problem herd, the bacterium is likely to be present in all cows. The
most common reservoirs of S. aureus are teat and hock skin and in particular skin lesions. Antibiotic treatment of S.
aureus mastitis is often not successful. Use of combination of systemic and intramammary treatment, as well as
increasing duration of treatment up to 5 days may improve cure rates. Cows infected with penicillin-resistant isolates
have very low cure rates and should preferably be culled. Development of antibiotic resistance of S. aureus isolates
should be monitored and emerging of MRSA among mastitis isolates needs particular attention. In control of S. aureus
mastitis, preventing spread of infection is most important. Infection sources i.e. chronically infected cows must be
removed from the herd. Predisposing factors such as teat and leg skin lesions must be prevented by maintaining good
barn environment. Teat dipping and targeted drying-off treatment are traditional means for control of S. aureus mastitis.
CNS have been considered as minor pathogens. However, their significance needs to be reconsidered as in many
countries they have become the most common agent causing subclinical mastitis. Herd prevalence of CNS mastitis can
be very high and intramammary infections caused by CNS may persist for long times. Approximately one half of CNS
infections cure spontaneously, but antibiotic treatment is necessary in clinical and in persisting cases. CNS can be
resistant to antibiotics used in therapy, and possible development of antibiotic resistance among CNS isolates should be
monitored. CNS can have characteristics of both contagious and environmental bacteria. It is possible that epidemiology
and virulence of CNS species differ. In the control of CNS mastitis focus should be on heifers as they are most often
infected. The clinical relevance of CNS mastitis depends on the goals of the herd; CNS infections cannot be ignored if
very low cell counts are wanted for production of premium milk quality.
References
Anderson KL, Lyman RL - Long-term persistence of specific genetic types of mastitis-causing Staphylococcus aureus
on three dairies. J Dairy Sci, 2006, 89:4551-4556.
Alves PDD et al. - Molecular characterisation of Staphylococcus aureus strains isolated from small and large ruminants
reveals a host rather than tissue specificity. Vet Microbiol, 2009, 137:190-195
Atalla H et al. - Antibody and cell-mediated immune responses to Staphylococcus aureus small colony variants and
their parental strains associated with bovine mastitis. Dev Comp Immunol, 2010, 34:1283-1290.
Almeida RA, Oliver SP - Interaction of coagulase-negative Staphylococcus species with bovine mammary epithelial
cells. Microb Pathog, 2001, 31:205-212.
Atkins K et al. - S. aureus IgG-binding proteins SpA and Sbi:host specificity and mechanisms of immune complex
formation. Mol Immunol, 2008, 45:1600-1611.
Barkema, H. W., Schukken Y.H., & Zadoks, R.N. Invited Review:The role of cow, pathogen, and treatment regimen in
the therapeutic success of bovine Staphylococcus aureus mastitis. J. Dairy Sci., 2006, 89:1877-1895.
Bengtsson B et al. - Antimicrobial susceptibility of udder pathogens from cases of acute clinical mastitis in dairy cows.
Vet Microbiol, 2009, 136:142-149.
Ben Zakour NL et al. - Genome-wide analysis of ruminant Staphylococcus aureus reveals diversification of the core
genome. J Bacteriol, 2008, 190:6302-6317.
Boerlin P et al. - Methods for Identification of Staphylococcus aureus Isolates in Cases of Bovine Mastitis. J Clin
Microbiol, 2003, 41:767-771.
van den Borne BHP et al. - Host adaptation of bovine Staphylococcus aureus seems associated with bacteriological cure
after lactational antimicrobial treatment. J Dairy Sci, 2010a, 93:2550-2558
van den Borne BHP et al. - Therapeutic effects of antimicrobial treatment during lactation of recently acquired bovine
subclinical mastitis:Two linked randomized field trials. J Dairy Sci, 2010b, 93:218-233
Brouillette E, Talbot BG, Malouin F - The fibronectin-binding proteins of Staphylococcus aureus may promote
mammary gland colonization in a lactating mouse model of mastitis. Infect Immun, 2003, 71:2292-2295.
Borm AA et al. - Effects of prepartum intramammary antibiotic therapy on udder health, milk production, and
reproductive performance in dairy heifers. J Dairy Sci, 2006, 89:2090-2098.
Botrel MA et al. - Distribution and antimicrobial resistance of clinical and subclinical mastitis pathogens in dairy cows
in Rhone-Alpes, France. Foodborne Pathog Dis, 2010, 7:479-487.
Brouillette E et al. - Persistence of a Staphylococcus aureus small-colony variant under antibiotic pressure in vivo.
FEMS Immunol. Med Microbiol, 2004, 41:35-41
Capurro A et al. - Comparison of a commercialized phenotyping system, antimicrobial susceptibility testing, and tuf
gene sequence-based genotyping for species-level identification of coagulase-negative staphylococci isolated from
cases of bovine mastitis. Vet Microbiol, 2009, 134:327-333.
Capurro A et al. - Identification of potential sources of Staphylococcus aureus in herds with mastitis problems. J Dairy
Sci, 2010a, 93:180-191.
Capurro A et al. - Genotypic variation among Staphylococcus aureus isolates from cases of clinical mastitis in Swedish
dairy cows. Vet J, 2010b, 185:188-192.
Compton CW et al. - Risk factors for peripartum mastitis in pasture-grazed dairy heifers. J Dairy Sci, 2007, 90:41714180.
Cucarella C et al. -Role of biofilm-associated protein bap in the pathogenesis of bovine Staphylococcus aureus. Infect
Immun, 2004, 72:2177-2185.
Catry B et al. - Reflection paper on MRSA in food producing and companion animals:epidemiology and control options
for human and animal health. Epidemiol Infect, 2010, 138:626-644.
Constable P, Pyörälä S, Smith G - Guidelines for antimicrobial use in cattle. In:Guide to antimicrobial use in animals.
Guardabassi, L., Jensen, L.B., & Kruse, H. (Eds.) Blackwell Publishing Ltd. Oxford, UK, 2008:143-160.
Deluyker HA, Van Oye SN, Boucher JF - Factors affecting cure and somatic cell count after pirlimycin treatment of
subclinical mastitis in lactating cows. J Dairy Sci, 2005, 88:604-614.
van Duijkeren E et al. - Methicillin-resistant staphylococci isolated from animals. Vet Microbiol, 2004, 103:91-97.
Erskine RJ, Wagner S, DeGraves FJ - Mastitis therapy and pharmacology. Vet Clin Food Anim, 2003, 19:109-138.
Fessler A et al. - Characterization of methicillin-resistant Staphylococcus aureus ST398 from cases of bovine mastitis. J
Antimicr Chemother, 2010, 65:619-625.
FINRES-Vet 2005-2006. Finnish veterinary antimicrobial resistance monitoring and consumption of antimicrobial
agents. Available at:http://www.evira.fi/uploads/WebShopFiles/1198141211941.pdf.
Foster TJ, Höök M - Surface protein adhesins of Staphylococcus aureus. A review. Trends Microbiol, 1998, 6:484-488.
Foster TJ - The Staphylococcus aureus "superbug". J Clin Invest, 2005, 114:1693-1696.
Fournier C et al. - Bovine Staphylococcus aureus:association of virulence genes, genotypes and clinical outcome. Res
Vet Sci, 2008, 85:439-48.
Fox LK, Zadoks RN, Gaskins CT - Biofilm production by Staphylococcus aureus associated with intramammary
infection. Vet Microbiol, 2005, 107:295-299.
Fox LK - Prevalence, incidence and risk factors of heifer mastitis. Vet Microbiol, 2009, 134:82-88.
Graber H et al. - Mastitis-related subtypes of bovine Staphylococcus aureus are characterized by different clinical
properties. J Dairy Sci, 2009, 92:1442-1451
Gröhn YT et al. - Effect of pathogen-specific clinical mastitis on milk yield in dairy cows. J Dairy Sci, 2004, 87:33583374.
Haenni M et al. - Staphylococcal bovine mastitis in France:enterotoxins, resistance and the human Geraldine
methicillin-resistant Staphylococcus aureus clone. J Antimicrob Chemother, 2011, 66:216-225
Halasa T et al. - Meta-analysis of dry cow management for dairy cattle. Part 1. Protection against new intramammary
infections. J Dairy Sci, 2010a, 92:3134-3149.
Halasa T et al. - Meta-analysis of dry cow management for dairy cattle. Part 2. Cure of existing intramammary
infections. J Dairy Sci, 2010b, 92:3150-3157
Hallén Sandgren C, Persson Waller K, Emanuelson U - Therapeutic effects of systemic or intramammary antimicrobial
treatment of bovine subclinical mastitis during lactation. Vet J, 2008, 175:108-117.
Haveri M et al. - Bacterial genotype affects the manifestation and persistence of bovine Staphylococcus aureus
intramammary infection. J Clin Microb, 2005, 43:959-961.
Haveri M et al. - Virulence genes in bovine Staphylococcus aureus mastitis of different clinical characteristics and
outcome. J Appl Microb, 2007, 103:993-1000.
Haveri M et al. - Molecular types and genetic profiles of Staphylococcus aureus isolated from bovine intramammary
infection and extramammary sites. J Clin Microb, 2008, 46:3728-3735.
Hendriksen RS et al. - Prevalence of antimicrobial resistance among bacterial pathogens isolated from cattle in different
European countries:2002-2004. Acta Vet Scand, 2008; 50:28. doi:10.1186/1751-0147-50-28
Herron-Olson, L et al. - Molecular correlates of host specialization in Staphylococcus aureus. 2007, PLoS ONE.
2:e1120.
Hovinen M, Haveri M, Pyörälä S - Sources of liner contamination and effect of back flushing of teat cups on isolation
of S. aureus. Hillerton, J.E. (ed.) Mastitis Research into practice. Proceedings of the 5th IDF International Mastitis
Conference, March 21-24 2010, Christchurch, New Zealand. P. 714.
Hyvönen P et al. - Effect of bovine lactoferrin on the internalization of coagulase-negative staphylococci into bovine
mammary epithelial cells under in vitro conditions. J Dairy Res, 2009, 76:144-151.
Jaglic Z et al. - Epidemiology and characterization of Staphylococcus epidermidis isolates from humans, raw bovine
milk and a dairy plant. Epidemiol Infect, 2010, 138:772-782.
Jørgensen HJ, Mørk T, Rørvik LM - The occurrence of Staphylococcus aureus on a farm with small-scale production of
raw milk cheese. J Dairy Sci, 2005, 8:3810-3817
Juhász-Kaszanyitzky E et al. - MRSA transmission between cows and humans. Emerg Infect Dis, 2007, 13:630-632
Koivula M et al. - Distribution of bacteria and seasonal and regional effects in a new database for mastitis pathogens in
Finland. Acta Agric Scand, 2007, 57:89.
Koskinen MT et al. - Field comparison of real-time PCR and bacterial culturing for identification of bovine mastitis
bacteria. J Dairy Sci, 2010, 93:5707-5715.
Kerro Dego O, van Dijk JE, Nederbragt H - Factors involved in the early pathogenesis of bovine Staphylococcus aureus
mastitis with emphasis on bacterial adhesion and invasion. A review. Vet Quart, 2002, 24:181-198
Kozytska S et al. - Identification of specific genes in Staphylococcus aureus strains associated with bovine mastitis. Vet
Microbiol, 2010, 145:360-365
Lam T et al. - Effect of natural infection with minor pathogens on susceptibility to natural infection with major
pathogens in the bovine mammary gland. Am J Vet Res, 1997, 58:17-22.
van Leeuwen W et al. - Host- and tissue-specific pathogenic traits of Staphylococcus aureus. J Bacteriol, 2005,
187:4584-4591
Los R et al. - A comparative analysis of phenotypic and genotypic methods for the determination of the biofilm-forming
abilities of Staphylococcus epidermidis. FEMS Microbiol Lett, 2010, 310:97-103.
Mazmanian SK et al. - Passage of heme-iron across the envelope of Staphylococcus aureus. Science 2003, 299:906909.
Melchior MB, Vaarkamp H, Fink-Gremmels J - Biofilms:a role in recurrent mastitis infections? Vet J, 2006, 171:398407.
Mellmann A et al. - Sequencing and staphylococci identification. Emerg Infect Dis, 2006, 12:333-336.
Middleton JR et al. - Effect of prepartum intramammary treatment with pirlimycin hydrochloride on prevalence of early
first-lactation mastitis in dairy heifers. JAVMA, 2005, 227:1969-1974.
Mitchell G et al. - A role for sigma factor B in the emergence of Stapylococcus aureus small-colony variants and
elevated biofilm production resulting from an exposure to aminoglycosides. Microb Pathogen, 2010, 48:18-27.
Monecke S et al. - Microarray based study on vierulence-associated genes and resistance determinants of
Stpahylococcus aureus isolates from cattle. Vet Microbiol, 2007, 125:128-140.
Moon JS et al. - Phenotypic and genetic antibiogram of methicillin-resistant staphylococci isolated from bovine mastitis
in Korea. J Dairy Sci, 2997, 90:1176-1185.
Mørk T et al. - Comparison of Staphylococcus aureus genotypes recovered from cases of bovine, ovine, and caprine
mastitis. J Clin Microbiol, 2005, 43:3979-3984.
Moroni P et al. - Short communication:Antimicrobial drug susceptibility of Staphylococcus aureus from subclinical
mastitis in Italy. J Dairy Sci, 2006, 89:2973-2976.
Newman KA et al. - Association of milk yield and infection status at dry-off with intramammary infections at
subsequent calving. J Dairy Res, 2010, 77:99-106.
Nickerson SC et al. - Evaluation of 0.5% and 1% iodofor teat dips on commercial dairies. J Dairy Sci, 1986, 69:16931698.
NMC. Current concept of bovine mastitis. National Mastitis Council. 3rd edition, 1987.
Nyman AK et al. - Risk factors associated with the presence of Staphylococcus aureus in milk and on hock skin.
Hillerton, J.E. (ed.) Mastitis Research into practice. Proceedings of the 5th IDF International Mastitis Conference,
March 21-24 2010, Christchurch, New Zealand. pp. 247-251.
NORM-VET. Usage of Antimicrobial Agents and Occurrence of Antimicrobial Resistance in Norway. 2005.
http://www.vetinst.no/nor/content/download/601/4917/file/NORM_NORM-VET_2005.pdf
Olde Riekerink RG et al. - Incidence rate of clinical mastitis on Canadian dairy farms. J Dairy Sci, 2008, 91:1366-1377.
Olde Riekerink RGM et al. - MRSA infections in Dutch dairy herds. The 5th IDF International Mastitis Conference,
March 21-24 2010, Christchurch, New Zealand. Proceedings, pp. 252-255.
Oliveira M et al. - Invasive potential of biofilm-forming staphylococci bovine subclinical mastitis isolates. J Vet Sci,
2011, 12:95-97.
Ohlsen K, Lorenz U - Immunotherapeutic strategies to combat staphylococcal infections. Int J Med Microbiol, 2010;
300:402-10.
Østerås O, Sølverød L, Reksen O - Milk culture results in a large Norwegian survey- effects of season, parity, days in
milk, resistance, and clustering. J Dairy Sci, 2006, 89:1010-1023
Otto M - Staphylococcus epidermidis - the "accidental" pathogen. Nature Rev, 2009, 7:555-564.
Parker KI et al. - Subclinical and clinical mastitis in heifers following the use of a teat sealant precalving. J Dairy Sci,
2007, 90:207-218.
Pereira UP et al. - Efficacy of Staphylococcus aureus vaccines for bovine mastitis:a systematic review. Vet Microbiol.
2011, 148:117-24
Paduch JH, Krömker V - Besiedlung von Zizenhaut und Zitzenkanal laktierender Milkrinder durch euterpatogene
Mikroorganismen (Colonization of the teat skin and the teat canal by mastitis pathogens in dairy cattle). Tierärzl. Praxis
Grosstiere, 2011, 2:71-76.
Park JY et al. - Detection of classical and newly described staphylococcal superantigen genes in coagulase-negative
staphylococci isolated from bovine intramammary infections. Vet Microbiol, 2011, 147:149-154.
Persson Waller K et al. - Incidence of mastitis and bacterial findings at clinical mastitis in Swedish primiparous cows influence of breed and stage of lactation. Vet Mic, 2009, 134:89-94.
Persson Waller K et al. - CNS species and antimicrobial resistance in clinical and subclinical bovine mastitis. Vet
Microbiol, 2011. doi:10.1016/j.vetmic.2011.04.006
Piepers S et al. - Prevalence and distribution of mastitis pathogens in subclinically infected dairy cows in Flanders,
Belgium. J Dairy Res, 2007, 74:478-483.
Piepers S et al. - Heifers infected with coagulase-negative staphylococci in early lactation have fewer cases of clinical
mastitis and higher milk production in their first lactation than noninfected heifers. J Dairy Sci, 2010, 93:2014-2024.
Piessens V et al. - Distribution of coagulase-negative Staphylococcus species from milk and environment of dairy cows
differs between herds. J Dairy Sci, 2011, 94:2933-44.
Piette A, Verschraegen G - Role of coagulase-negative staphylococci in human disease. Vet Microbiol, 2009, 134:4554.
Pitkälä A et al. - Bovine mastitis in Finland 2001 - prevalence, distribution of bacteria and antimicrobial resistance. J
Dairy Sci, 2004, 87:2433-2441.
Pyörälä S, Pyörälä E - Efficacy of parenteral administration of three antimicrobial agents in treatment of clinical
mastitis in lactating cows:487 cases (1989-1995). JAVMA, 1998, 212:407-412.
Pyörälä S, Taponen S - Coagulase-negative staphylococci - emerging mastitis pathogens. Vet Mic, 2009, 134:3-8.
Rachid S et al. - Effect of subinhibitory antibiotic concentrations on polysaccharide intercellular adhesin expression in
biofilm-forming Staphylococcus epidermidis. Antimicr Agents Chemother, 2000, 44:3357-3363.
Rajala-Schultz PJ et al. - Antimicrobial resistance and genotypic characterization of coagulase-negative staphylococci
over the dry period. Vet Microbiol, 2009, 134:55-64.
Newman KA et al. - Association of milk yield and infection status at dry-off with intramammary infections at
subsequent calving. J Dairy Res, 2010, 77:99-106.
Robert A, Seegers H, Bareille N - Incidence of intramammary infections during the dry period without or with
antibiotic treatment in dairy cows - a quantitative analysis of published data. Vet Res, 2006, 37. 25-48.
Said KB et al. - Regional profiling for determination of genotype diversity of mastitis-specific Staphylococcus aureus
lineage in Canada by use of clumping factor a, pulsed-field gel electrophoresis, and spa typing. J Clin Microbiol, 2010,
48, 375-386.
Sampimon OC et al. - Prevalence and herd-level risk factors for intramammary infection with coagulase negative
staphylococci in Dutch dairy herds. Vet Microbiol, 2009a, 134, 37-44.
Sampimon OC et al. - Effect of prepartum dry cow antibiotic treatment in dairy heifers on udder health and milk
production. J Dairy Sci, 2009b, 92:4395-4403.
Sampimon OC et al. - The effect of coagulase-negative staphylococci on somatic cell count in Dutch dairyherds. J
Dairy Res, 2010, 77:318-324.
Sawant AA, Gillespie BE, Oliver SP - Antimicrobial susceptibility of coagulase-negative Staphylococcus species
isolated from bovine milk. Vet Microbiol, 2009, 134:73-81.
Schukken YH et al. - CNS mastitis:Nothing to worry about? Vet Microbiol, 2009, 134:9-14.
Schwarz D et al. - Somatic cell counts and bacteriological status in quarter foremilk samples of cows in Hesse,
Germany - a longitudinal study. J Dairy Sci, 2010, 93:5716-5728.
Seo YS et al. - Biofilm-forming associated genotypic and phenotypic characteristics of Staphylococcus spp. isolated
from animals and air. Res Vet Sci, 2008, 85:433-438.
Simojoki H et al. - Host response in bovine mastitis experimentally induced with Staphylococcus chromogenes. Vet
Microbiol, 2009, 134:95-99.
Simojoki H et al. - Association with biofilm formation of coagulase-negative staphylococci isolated in bovine mastitis
and persistency of infection. Seminar on Coagulase-negative staphylococci, Ghent, Belgium, September 15-16, 2010.
Proceedings, 37.
Simojoki H et al. - Innate immune response in experimentally induced bovine intramammary infection with
Staphylococcus simulans and S. epidermidis. Vet Res, 2011, 42:49. http://www.veterinaryresearch.org/content/42/1/49.
Simojoki H et al. - Biofilm formation of coagulase-negative staphylococci isolated in bovine mastitis and its association
with persistency of infection. In:Proceedings of the Seminar on Coagulase-Negative Staphylococci in the Bovine:1516.9.2010; Ghent, Belgium.
Smith EM et al. - Multilocus sequence typing of intercontinental bovine Staphylococcus aureus isolates. J Clin
Microbiol, 2005, 43:4737-4743
Sommerhäuser J et al. -The epidemiology of Staphylococcus aureus infections from subclinical mastitis in dairy cows
during a control programme. Vet Microbiol, 2003, 96:91-102.
Stevens NT et al. - Biofilm characteristics of Staphylococcus epidermidis isolates associated with device-related
meningitis. J Med Microbiol, 2009, 58:855-862.
Stutz K, Stephan R, Tasara T - Spa, clfa, and fnba genetic variations lead to staphaurex test-negative phenotypes in
bovine mastitis Staphylococcus aureus isolates. J Clin Microbiol, 2011, 49:638-646.
Supré K et al. - Staphylococcus devriesei sp. nov., isolated from teat apices and milk of dairy cows. Int. J Syst Evol
Microbiol, 2010, 60:2739-2744.
Supré K et al. - Some coagulase-negative Staphylococcus species affect udder health more than others. J Dairy Sci,
2011, 94:2329-2340.
SVARM, 2008. In:Bengtsson, B., Englund, S., Greko, C. & Grönlund-Andersson, U. (Eds.) Swedish Veterinary
Antimicrobial
Resistance
Monitoring.
National
Veterinary
Institute,
Uppsala,
Sweden.
http://www.sva.se/upload/Svarm%202008%20vers%2019%20maj.pdf
Swinkels JM, Hogeveen H, Zadoks RN - A partial budget model to estimate economic benefits of lactational treatment
of subclinical Staphylococcus aureus mastitis. J Dairy Sci, 2005, 88:4273-4287.
Talbot BG, Lacasse P - Progress in the development of mastitis vaccines. Livestock Prod Sci, 2005, 98:101-13.
Taponen S et al. - Efficacy of targeted 5-day combined parenteral and intramammary treatment of clinical mastitis
caused by penicillin-susceptible or penicillin-resistant Staphylococcus aureus. Acta Vet Scand, 2003, 44:53-62
Taponen S et al. - Clinical characteristics and persistence of bovine mastitis caused by different species of coagulasenegative staphylococci identified with API Or AFLP. Vet Microbiol, 2006, 115:199-207.
Taponen S et al. - Bovine intramammary infections caused by coagulase-negative staphylococci may persist throughout
lactation according to Amplified Fragment Length Polymorphism-based Analysis. J Dairy Sci, 2007, 90:3301-3307.
Taponen S, Björkroth J, Pyörälä S - Coagulase-negative staphylococci isolated from bovine extramammary sites and
intramammary infections in a single dairy herd. J Dairy Res, 2008, 75:422-429.
Taponen S et al. - Staphylococcus agnetis sp. nov., a coagulase-variable species from bovine subclinical and mild
clinical mastitis. Int J Syst Evol Microbiol, 2011. doi:10.1099/ijs.0.028365-0
Tenhagen BA et al. - Prevalence of mastitis pathogens and their resistance against antimicrobial agents in dairy cows in
Brandenburg, Germany. J Dairy Sci, 2006, 89:2542-2551.
Thorberg BM et al. - Pheno- and genotyping of Staphylococcus epidermidis isolated from bovine milk and human skin.
Vet Microb, 2006, 115:163.
Thorberg BM et al. - Bovine subclinical mastitis caused by different types of coagulase-negative staphylococci. J Dairy
Sci, 2009, 92:4962-4970.
Tuchscherr L et al. - Staphylococcus aureus small-colony variants are adapted phenotypes for intracellular persistence. J
Inf Dis, 2010, 202:1031-1040.
Turutoglu H et al. - Methicillin and aminoglycoside resistance in Staphylococcus aureus isolates from bovine mastitis
and sequence analysis of their mecA genes. Vet Res Commun, 2009, 33:945-956.
Waage S et al. - Spread of Staphylococcus aureus resistant to penicillin and tetracycline within and between dairy
herds. Epidemiol Infect, 2002, 129:193-202
Vanderhaeghen W et al. -Methicillin-resistant Staphylococcus aureus (MRSA) ST398 associated with clinical and
subclinical mastitis in Belgian cows. Vet Microbiol, 2010, 144:166-171.
Whist AC, Österås O, Solverod L - Clinical mastitis in Norwegian herds after a combined selective dry-cow therapy
and teat-dipping trial. J Dairy Sci, 2006, 89:4649-4659.
Zadoks RN, Watts JL - Species identification of coagulase-negative staphylococci:Genotyping is superior to
phenotyping. Vet Microbiol, 2009, 134:20-28.
Zhang S, Maddox CW - Cytotoxic activity of coagulase-negative staphylococci in bovine mastitis. Infect Immun, 2000,
68:1102-1108.
Practical application of a tool to evaluate mastitis risk factors and costs
in 25 Italian dairy herds
A. ZECCONI - Università degli Studi di Milano, DIPAV, Italy
[email protected]
R. PICCININI - Università degli Studi di Milano, DIPAV, Italy
A practical tool was developed to investigate mastitis risks and costs in dairy herd. This tool is based on a questionnaire
and on random sampling of quarter milk. The questionnaire was developed to collect the data in an objective and
rationale way, avoiding personal interpretation of data. The aim was to evaluate the different critical points within a
dairy herd (i.e. milking, therapy, bedding hygiene) and to calculate mastitis cost by partial budget analysis. Random
sampling of quarter milk is based on epidemiological approach, to maximize the chance to identify prevalent pathogens.
Questionnaires and milk samples were collected in 25 Italian dairy herds during 2010. Data were analyzed to assess
mastitis costs, bacteria and risk factors. The results showed that in each dairy herd a prevalent source of infections could
be identified (contagious or environmental pathogens). More interestingly, the cost of mastitis showed very large
variations mostly due to the different protocols applied in each farm and not to the different pathogens identified. The
tool developed showed to be practical and useful to identify prevalent pathogens and critical factors at herd level, and to
improve herd sustainability by applying more rational and efficient therapeutic protocols.
Relationship between teat end shape and callosity ring and mastitis bacteria
isolated in quarters of Norwegian Red cows
R.T. GARMO - BioKapital, Hamar, Norway
[email protected]
S. WAAGE, O. REKSEN - Norwegian School of Veterinary Science, Oslo, Norway
S. SVILAND - National Veterinary Institute, Oslo, Norway
A single evaluation of teat end shape and teat end callosity ring thickness and roughness was performed in 1010
lactating Norwegian Red cows located in 49 dairy farms. Milk samples for bacteriological examination were collected
from each quarter before milking. All teats were examined by the same evaluator before milking. Teat end shape was
classified as round, flat, pointed or inverted. The thickness of the callosity ring was divided in five classes; none, slight,
moderate, thick and extremely thick whereas the callosity ring roughness was classified either as smooth or rough. The
average day in milk interval was 160.7 d (SE±3.14) and the average four weeks daily milk yield was 26.5 kg (SE±0.24).
The distribution of teat end shape was 44.2, 42.3, 6.1, and 7.3% for round, flat, pointed and inverted, respectively. The
distribution of callosity ring thickness was 25.9, 55.4, 15.1, 2.4, and 0.5% for none, slight, moderate, thick and
extremely thick, respectively. The distribution of roughness was 74.7% for smooth and 25.3% for rough callosity rings.
Mastitis bacteria were isolated in 16.3% of the quarter samples with following distribution; 9.2% coagulase negative
staphylococci, 3.3% S. aureus, 1.5% S. dysgalactia, and 2.3% other bacteria. The likelihood of a positive diagnosis for
mastitis bacteria on the quarter level was assessed in a logistic model with herd and cow as random factors. The
following predictors were associated with a positive diagnosis; teat end shape, callosity ring, quarter, parity, and the
natural logarithm of somatic cell count. The odds ratio for isolation of mastitis bacteria in a quarter was 1.7 for teats
with rough compared to teats with non callosity ring, 1.9 for pointed compared to round teat end shape, 1.6 for hind
quarters compared to right front quarter, and 1.4 for>2.parity compared to 1.parity cows.
In conclusion, a single evaluation of teat end shape and callosity can be used to estimate the risk for isolation of mastitis
bacteria at the quarter level, independent of days in milk. Evaluation of teat end shape and callosity ring can be useful
for culling decisions on an individual level.
Acute Mastitis with SIRS: the impact of different treatment regimes
on acute phase proteins and milk quality
L. PODSTATZKY - AREC Raumberg-Gumpenstein, Wels, Austria
[email protected]
P. WINTER - Veterinary University Vienna, Vienna, Austria
This study focuses on additional therapy with non-steroidal anti-inflammatory drugs (NSAID) and infusions of
parenteral NaCl solutions to antibiotic treatment in coliform mastitis in the field.
Material and methods
50 cows with typical inclusion criteria (clinical score) were involved in this study. All cows were treated with the
antibiotic marbofloxacin (2 mg/kg once a day for three days). The cows were divided in three upper groups (no
infusion, 0.9% NaCl, 7.2% NaCl) and three sub groups (without and with the NSAID tolfenamic acid (2 mg/kg)). Blood
and milk samples were examined at 0, 12, 24, 48, 72 hours and 3 weeks after mastitis occurrence. Blood samples were
examined for WBC, serumamyloid A, haptoglobin and tumor necrosis factor alpha (TNFalpha). Milk samples were
used for CMT and bacterial diagnosis.
Results
Of these 50 cows 28 were tested positive for E. coli, 5 positiv for Klebsiella sp., 2 positiv for A. pyogenes, 6 positive for
Sc. spp. and 4 positiv for S. aures. 5 were negative in all milk samples. Until 72 hours milk samples from cows with S.
aureus, Sc. pp and Klebsiella remained positive. The number of E. coli and Klebsiella positive cows reduced from 33 to
12 until 72 hours. At the end of the observation period all milk samples were negative, except one sample with Sc. sp.
and one with S. aureus.
WBC increased to physiological values within 24 hours. Haptoglobin and SAA increased until 48 hours. TNFalpha
remained high over 12 hours only in the 7.2% group. NSAID had non influence on haptoglobin and SAA but TNFalpha
was 2-3 times higher with NSAID over the whole examination period. Infusion and NSAID had no influence on
bacteriological cure rate and CMT. CMT was high until 72 hours and decreased within 3 weeks.
Conclusion
These data show that coliform mastitis is caused mainly by E. coli but also other bacteria. Treatment with infusions and
NSAID seemed to have some influence in blood parameters, whereas the influence of these treatments to the recovery
of milk parameters seemed to be very little.
Follow-up study of the use and the effects of a vaccine against staphylococcal
and coliform mastitis (Startvac®, Hipra) in French dairy farms
F. SERIEYS - Filière Blanche, Rennes, France
[email protected]
A follow-up of vaccination with a vaccine aimed to prevent staphylococcal and coliform mastitis (Startvac®, Hipra) has
been carried out by 9 vet practitioners in 11 dairy farms from their practices in different French dairy regions. The aim
was to observe the practical implementation of this three injection vaccination in field conditions and to assess its
effects on milk somatic cell counts, incidence of clinical mastitis, number of antibiotic treatments (main criteria) and
milk yield (secondary criterium) during the 4 first months of lactation.
The chosen herds had to show at least 50% of bacteriological isolations corresponding to the species included in the
activity spectrum of the vaccine. In each farm, primiparous and multiparous cows were alternatively vaccinated or not
(intra-herd control group) in the order of their expected calving dates.
The ratio of the number of bacteriological analysis effectively carried out before herd inclusion to the number of
included cows varied from 10% to 67% according to the farm. This preliminary bacteriological evaluation to select the
eligible herds appeared to the vets as the main constraint to implement vaccination. Globally, 75% of the pathogens
isolated from the different included herds corresponded to the valences of the vaccine.
The edition of a vaccination calendar calculated from reliable fertilizing insemination dates, has appeared to be
indispensable to make easier the observance of the vaccination protocol by the farmers. Nevertheless, significant gaps
between the real and the recommended vaccination dates were observed, particularly for the second injection ten days
before calving.
In multiparous cows, this vaccination resulted in a reduction of more than 25% of milk somatic cell counts, i.e. about
100 000 cells/ml less (P<0.05), and in nearly 30% less antibiotic treatments during lactation (P<0.05) compared to the
intra-herd control group. The differences in clinical mastitis incidence (P=0.13) and milk yield (P=0.59) were not
statistically significant. In primiparous cows, there were no statistically significant difference whatever the criterium
considered, probably because the low number (110) of included animals.
Detection of Staphylococcus aureus Genotype B in samples of routine milk
recording and bulk tank milk with PCR
C. SYRING - Clinic for Ruminants, Vetsuisse-faculty, University of Bern, Switzerland
[email protected]
R. BOSS, H. GRABER - Research Station Agroscope Liebefeld-Posieux, Switzerland
A. STEINER - Clinic for Ruminants, Vetsuisse-faculty, University of Bern, Switzerland
Recently, Boss et al. (J. Dairy Sci. 2011) developed and evaluated a novel real-time quantitative PCR assay for
detecting Staphylococcus aureus genotype B (GTB) in bulk tank milk (BTM).
This subtype is pathogenic and contagious with normally more than 40% of the cows infected and causes, therefore,
great economic loss in Swiss dairy herds. The detection of this subtype in BTM would greatly facilitate its control.
The assay is based on the simultaneous detection of 3 GTB-typical target sequences including 2 enterotoxin genes and a
polymorphism within the leukotoxin E gene. The test is characterized by an excellent analytical sensitivity and
specificity including a high repeatability. The detection limit in milk was 40 cfu/ml which corresponds to a calculated
detection limit of 1 GTB-positive cow among 138 cows. In a cross sectional study, the assay was now evaluated for its
diagnostic properties under field conditions. In total, 56 dairy herds were assessed whereby 21 were GTB-positive and
35 were GTB-negative (control herds). BTM samples and four-quarter milk samples were collected whereby the latter
of each herd were pooled (herd pool samples). Considering BTM-samples, the diagnostic sensitivity and specificity of
the assay were both higher than 95% indicating that the test allowed to safely discriminate between GTB-positive and negative herds. The same was also true for the herd pool samples. In addition, the assay can be widely automated
allowing high throughput. Furthermore, the test is characterized by a high cost efficiency. Because of its favourable
properties, the assay is expected to play an important role in eradicating and controlling of S. aureus GTB in Swiss
dairy herds using BTM samples.
Analysing dairy health through farmer’s competencies and advice makers:
examples of dairy cow mortality and udder health
D. RABOISSON - Université de Toulouse, INP, ENVT, US 0685, ODR, Toulouse, France
[email protected]
E. CAHUZAC, G. ALLAIRE - INRA, US 0685, ODR, F-31326 Toulouse
P. SANS - Université de Toulouse, INP, ENVT, Toulouse, France
The aim was to show the importance of farmer’s competencies and capabilities in dairy health management. From
exhaustive databases, 2005 and 2006 dairy cow mortality rate (MO-RA) and composite weight mean cow SCC
(CMSCC) were explained with several farm level variables (herd size …) and 3 municipal variables (cattle density,
human density and grass on overall agricultural land ratio). Statistical analyses were performed with 2 linear models
(MO-RA>0, sample bias Heckman method; CMSCC). Models were applied to protected designation of origin (PDO)
cheese products: Cantal (CAN) and Saint-Nectaire (STNEC). Two processing ways were tested: factory made (FAC) or
farm made (by the farmer itself) (FARM). Models were also applied separately to each area (11 breeding systems) to
perform intra-municipal autocorrelation analysis on model residuals.
The percentage of farms with no cow death is lower for FARM compared to FAC (CAN and STNEC) (P<0.05); MORA is higher for FARM compared to FAC (STNEC) (P<0.05). MO-RA of units with mortality is lower for FARM
compared to FAC (STNEC) (P<0.05). CMSCC is lower for FARM compared to FAC (CAN, 2006) (P<0.05). Identical
tendency is reported for STNEC (P>0.05). This suggests some competency modifications among farmers making
cheese in farm: sensitivity toward mortality is decreased whereas sensitivity toward udder health is increased. The
stakes of milk quality are very high for farm cheese maker (non pasteurized milk) compared to others (pasteurized milk,
sold to industrial). Moreover, results show that FARM had competencies to manage mortality (as suggested by lower
MO-RA-0-excluded compared to FAC), but that competencies must be revealed into capabilities (i.e. practices or risk
factors). This showed the necessity of regular advice to increase sensibility of farmers to health issues.
Intra-municipal correlations of residuals were positive and moderate for MO-RA and CMSCC for most of areas
(P<0.05). Higher correlations were observed at a supra municipality level. The residual correlations showed a
contextual effect that cannot be reduced to natural conditions (included in the models). This effect, common to local
farmers, can be due to farmer’s relationship among municipality, but also to the effect of common advisers, as vets or
other extern health managers.
FFrreenncchh B
Buuiiaattrriiccss A
Assssoocciiaattiioonn S
Syym
mppoossiiuum
m
Emerging and evergreen
re-emerging diseases
The Epizootic Hemorrhagic Disease (EHD) and EHD-virus
J. BRENNER - Kimron Veterinary Institute, Bet Dagan, Israel
[email protected]
Worldwide Epizootic Hemorrhagic Disease (EHD) in cattle before 2006
Originally, Epizootic Hemorrhagic Disease (EHD) was referred to as "EHD of deer" (Maclachlan & Osburn, 2004).
This name remained valid up to the recent appearances of the same disease in cattle in Israel (Yadin et al., 2007, 2008)
and the Maghreb region of North Africa, Turkey (Temizel et al., 2009) and Reunion Islands (Bread et al., 2004).
EHDV is transmitted, as are the bluetongue (BT) and Ibaraki (IB) viruses (BTV and IBV, respectively), by midges of
the Culicoides species (Mellor et. al., 200). The best definitions of the symptoms that appear after ruminant exposure to
EHDV were given by Radostitis et al. (2007). Radostitis et al. (2007) included the BT, IB and EDH viruses as the
causative agents of the hemorrhagic complex in ruminants.
Shope et al., (1955) studied EHDV in wild ruminants and stated that HD outbreaks had been occurring periodically in
the USA since 1890, and had been variously diagnosed as blackleg, mycotic stomatitis, blacktongue or haemorrhagic
septicemia. A similar disease, characterized by fever and stomatitis in cattle, occurred in Japan (Inaba 1975). Initially it
was confused with other epizootic diseases in Japanese cattle, including "bovine epizootic fever" and "bovine influenza"
and was eventually called "Ibaraki disease" (Goto 1959). The disease was also refereed to as "bluetongue-like" disease
in Japan (Omori et al., 1969a, b; Omori 1961; Inaba et al., 1966). Ibaraki virus is now recognized as a strain of EHDV
serotype 2, and it shares cross-reactive epitopes with other EHDV strains/serotypes (Nara Periera et al., 2000).
A feature of EHD is that it is caused by more than one serological virus type. This feature is shared by some other viral
diseases including BT, foot-and-mouth disease, and vesicular stomatitis and influenza. The clinical manifestations of
EHD are, in general, similar to those caused by BTV and include oedema of the conjunctiva, the oral and nasal mucous
membranes, and the muzzle (Radostits et al., 2007). The generic term "hemorrhagic diseases" has been adopted to
encompass BT, IB, and EHD diseases. In some cases of IBD and EHD, erosions and/or ulcerations develop at the
coronets, causing lameness, and the tongue can become swollen, resembling the characteristic clinical signs of BT.
Up to 2006 EHD was reported only from North America (where it appeared only in wild ungulate), Africa, Indonesia,
and the Pacific Islands of the tropics.
EHDV
EHDV, the causative agent of (Epizootic) HD is a member of the family Reoviridae, genus Orbivirus. The serogroup of
EHDV (also) comprises nine distinct serotypes, distinguished on the basis of neutralizing tests. EHDV are nonenveloped viruses with ten double-stranded RNA segments, a genomic structure that endows relative resistance to
ultraviolet and &-irradiation. The inner core consists of the viral proteins VP1, VP3, VP4, VP6 and VP7, and the outer
structures consist of VP2 and VP5. The non-structural proteins are NS1, NS2 and NS3. This genetic feature is shared by
the entire Orbivirus group, of which BTV is considered the prototype (Campbell et al., 1978).
What are the clinical criteria to define the hemorrhagic disease complex?
As already mentioned, there are many Orbiviruses responsible for hemorrhagic diseases in ruminants. The best known
is the BTV, which is responsible for BT, a severe hemorrhagic disease in sheep and cattle. The concept of a
hemorrhagic complex is now recognized as a legitimate descriptive feature of Orbiviruses infections. The BT disease(s)
is considered the cornerstone of the clinical manifestations that appear during and after BTV infections, especially in
cattle. Moreover, Elbers et al. (2008a, b, c; 2009) has introduced the concept of BT-attributed clinical signs. These signs
included fever, anorexia, dysphagia, ulcerative and necrotic lesions of the oral mucosa, hyperemia and oedema of the
conjunctival mucosa, sore muzzle, hyperemia of the teats and udder, hemorrhage, dehydration and lameness (Darpel et
al., 2007l; Eschbaumer et al., 2010).
Brenner et al., (2011) have described seven distinct syndromes that have been attributed to BTV infection in cattle in
Israel: foot rot-like syndrome, sore nose syndrome, subcutaneous emphysema syndrome, red/rough udder syndrome,
bluetongue/epizootic haemorrhage disease systemic syndrome, maladjustment-like syndrome, and post-BT acute severe
pleuropneumonia. These syndromes demonstrate the damage that an Orbivirus can inflict on the cattle population,
especially on naïve populations.
The key question to be asked by the buiatric forum is: Would the catastrophe situation seen during BT epidemics repeat
itself, if EHDV appeared in Europe?
The clinical features attributed to EHDV infections in dairy cattle in Israel are described below.
EHDV outbreak in Israel
On September 5, 2006, The Israeli Veterinary Field Services were notified of a novel disease syndrome in cattle; the
first clinical signs had been seen towards the end of August. The outbreak was first noticed on several dairy farms in the
southern Jordan River Valley (part of the Rift Valley) in Israel; affected cows showed a 10 to 20 percent reduction in
milk production and loss of appetite, followed by clinical signs of reduced rumination, a short-term low fever, weakness
and stiff gait. Additional signs included prominent serous to purulent nasal discharge, excessive salivation, and nasal
and lip redness, with scaling and tongue swelling, cyanosis and erosions. Petechiae observed on the tips of the lingual
and buccal papillae were similar to those noted in several other hemorrhagic syndromes in ruminants (Radostits et al.,
2007). Some animals showed ocular signs of epiphora, conjunctival hyperaemia and palpebral oedema. Some animals
had a stiff gait, showed muscle tremors of the appendages and became recumbent. Several animals exhibited red to
purple discoloration of the udder and hoof oedema with echymotic hemorrhages. However, not all these clinical signs
were seen on any one farm. Interestingly, this clinical feature, namely, lack of uniformity of syndromes, was a
characteristic feature of the 2008-2011 BT outbreaks in Israel (Brenner et al., 2010; 2011). Throughout August and
September 2006, (E) HD outbreaks spread north and south along the Jordan Valley into the Upper Galilee and Dead Sea
areas. From the beginning of October, the disease also spread west and east, to dairy farms in the Jezre’el Valley and
the Golan Heights. Several foci also appeared on the Israeli coastal plain. Some or all of the clinical signs of (E) HD
were reported in a total of 105 cattle herds (80 dairy herds, 21 beef herds and four feedlots). Within-herd morbidity
ranged from 5 to 80 percent in the dairy herds, with variable involvement of replacement heifers; the mortality was less
than 1 percent. The duration of the disease in individual animals was reported to range between three and 30 days.
There were no reports of a distinctive disease in sheep or goats in the affected compartments during that time.
According to Kedmi et al., (2010) the number of dairy cattle herds that seroconverted (i.e., was found serologically
EHDV positive) was 102, and the culling rates rose by 1.4.
In Israel, the first suggested diagnosis was bovine ephemeral fever (BEF), an arboviral disease that had previously
appeared in the same season and in the same regions (Yeruham et al., 2005; 2010). However, the clinical signs in the
present outbreak were more like those associated with the BT outbreaks in cattle that had been reported in northern
Europe during August 2006 (Thiry et al., 2006; Toussaint et al., 2006). Although the observed lesions were not typical
of BEF, several BEF-positive reactions were obtained in reverse transcriptase-PCR (RT-PCR) assays (Brenner
unpublished data). The differential diagnosis took BT into consideration, but because BT induces some of the same
clinical signs in small ruminants and there was no ovine involvement in the present outbreak, EHDV infection was
considered as a possible cause.
Because EHD had not been previously seen in Israel or elsewhere in the region, no diagnostic procedures were readily
available. Samples were therefore sent to the BT reference laboratory at the Institute for Animal Health, Pirbright.
Differential diagnosis
The differential diagnosis should take in account the following diseases: BT, Bovine Viral Diarrhea, Foot-Mouth,
Infectious Bovine Rhinotracheitis, Vesicular Stomatitis, Sheep-Associated Malignant Catarrhal Fever, and Bovine
Ephemeral Fever.
Laboratory diagnosis
Samples
For virus isolation and detection whole blood in EDTA and/or heparin (?) and/or spleen, lungs, lymph nodes, and liver
are needed. For serological tests (also for seroconversion) paired serum samples, 3-5 ml each, are needed.
Can the economic loss associated with EHDV infection in cattle in Israel bear a message to the EU market?
The Israeli group headed by Kedmi et al. (2011), tried to evaluate the loss of productivity during the 2006 EHD
epidemic in Israel. They found a total loss of 26.5 US$/cow, i.e., 0.55% of the annual average total production value of
a dairy cow. Thus, the epidemic, which lasted only 3 months, engendered a loss equal to 0.5% of the Israeli dairy cattle
industry’s annual production.
Could the EHDV inflict a similar productivity loss to the European ruminant industry if it emerged in the EU?
Moreover, could the damage inflicted on the ruminant industry during the European BT epidemics repeat itself,
especially considering that the EHD outbreak lasted only 3 months in Israel?
Control
Generally speaking, the same measures adopted by the EU to halt the BT epidemics, seem to be adequate against the
EHD as well. Vaccines should be considered by vaccine manufacturers. The humoral immunity elicited by the killed
vaccines is serotype specific, and therefore, preventive measures should consider all nine serotypes. The efficient live
and killed vaccines against IBDV and the excellent results obtained against the BTV in Europe should give rise to
optimism for controlling EHD using vaccines. Priority should be given to the serotypes already detected around the
Mediterranean Basin, Israel (Yadin et al., 2007, 2008), Turkey (Temizel et al., 2009), and the Maghreb region, namely
types 7 and 6 (formerly 318), respectively.
Consideration and conclusion remarks
Haemorrhagic diseases caused by Orbiviruses such as BTV and EHDV have been considered seasonal because they are
transmitted by hematophagous biting midges (Culicoides species). This view changed during the last BT outbreak in
Israel because BTV isolations occurred almost every month from September 2008 through March 2011 (Brenner
personal communication). In Israel, the major vector species for BTV (and possibly EHDV) is thought to be Culicoides
imicola. However, the source and the vector of the EHDV outbreaks described here are still unknown.
The northern valleys of Israel and to a lesser extent the Israeli coastal plain and the Arava (an arid region that extends
southwards from the Jordan river valley and the Dead Sea) have all suffered several infectious viral diseases during the
past decade, all of which are probably spread by biting insects. BEF virus (BEFV), which was formerly thought to
appear cyclically in Israel every 7 to 15 years, reappeared in 1999, 2000, 2001 and 2004 (Yeruham et al., 2005, 2010).
BEF appeared again in 2006 and 2010 (Brenner personal communication)
The Akabane virus, the causative agent of the arthrogryposis and hydrancephaly/ microencephaly syndromes, which
appeared in the northern valleys of Israel in 1969/70 (Markusfeld-Nir and Mayer 1971; Kalmar et al., 1975; Shimshony
1980), appeared again in 2001 and 2003 (Brenner et al., 2004a, b). While the Akabane virus had previously been
thought to infect only northern Israel (Shimshony 1980), infections in other areas were found in all the recent outbreaks,
save the 2001 outbreak. During subsequent years, farms all over Israel were affected, except for those located in the
mountains of Upper Galilee, the Golan Heights, Jerusalem and the Mount Carmel range, at altitudes above 500 m
(Brenner et al. 2004b). Surprisingly, the Akabane virus strain involved in the 2001-2003 outbreak(s) represented a new
lineage not previously encountered (Stram et al., 2004).
During the investigation of the EHD outbreaks in Israel, Brenner et al., (2004c) applied epidemiological rules designed
to deal with "emerging diseases", which allowed relatively quick identification of the causative agent, EHDV.
Previously, several tentative or small-scale serological surveys had been carried out in Israel, to evaluate observations
made by field practitioners regarding the appearance of sporadic cases of haemorrhagic disease. Although it had
initially been suggested that these might be ID, the results were inconclusive (Brenner, personal communication).
It is important to recognize that the vector-borne diseases that Israel has recently experienced could also spread to the
European continent. The appearance of several waves of BTV infections in south-east and south Europe and around the
Mediterranean shores, and in the north-central region of Europe (Thiry et al., 2006; Toussaint et. al., 2006), may be only
the first indications of such a spread (Purse et al., 2005).
A delayed response to the BTV-8 outbreak in northern Europe is a fact. Some authors blamed the farmers and
veterinarians for the delay in confirmation of the disease (Elbers et al., 2009); their attitude was partly due to the fact
that BT had never been previously seen in this part of Europe, so awareness was likely lacking during the initial stages
of the epidemic. The danger of a similar delayed response to an EHDV outbreak is ever present in light of the low
awareness of the EHDV in Europe, especially among veterinary field practitioners, who are the first to detect (or fail to
detect) new clinical signs on dairy cattle farms.
Abstract
Epizootic Hemorrhagic Disease Virus (EHDV) is the causative agent of (Epizootic) HD, a member of the family
Reoviridae, genus Orbivirus. EHDV is probably transmitted, by midges of the Culicoides species. Originally, EHD was
referred to as "EHD of deer". This name remained valid up to the recent appearances of the same disease in cattle in
Israel and the Maghreb region of North Africa, Turkey and Reunion Islands. A feature of EHD is that it is caused by
more than one serological virus type. The clinical manifestations of EHD are, in general, similar to those caused by
BTV and include oedema of the conjunctiva, the oral and nasal mucous membranes, and the muzzle and erosions and/or
ulcerations develop at the coronets, causing lameness, and the tongue can become swollen. On September 5, 2006, the
Israeli Veterinary Field Services were notified of a novel disease syndrome in cattle. The outbreak was first noticed on
several dairy farms in the southern Jordan River Valley in Israel; affected cows showed a 10 to 20 percent reduction in
milk production and loss of appetite, followed by clinical signs of reduced rumination, a short-term low fever, weakness
and stiff gait. Additional signs included prominent serous to purulent nasal discharge, excessive salivation, and nasal
and lip redness, with scaling and tongue swelling, cyanosis and erosions. Petechiae observed on the tips of the lingual
and buccal papillae were similar to those noted in several other hemorrhagic syndromes in ruminants. Some animals
showed ocular signs of epiphora, conjunctival hyperaemia and palpebral oedema. Several animals exhibited red to
purple discoloration of the udder and hoof oedema with echymotic hemorrhages. The number of dairy cattle herds that
seroconverted (i.e., was found serologically EHDV positive) was 102, and the culling rates rose by 1.4. The duration of
the disease in individual animals was reported to range between three and 30 days. There were no reports of a
distinctive disease in sheep or goats in the affected compartments during that time. The differential diagnosis should
take in account the following diseases: BT, Bovine Viral Diarrhea, Foot-Mouth, Infectious Bovine Rhinotracheitis,
Vesicular Stomatitis, Sheep-Associated Malignant Catarrhal Fever, and Bovine Ephemeral Fever. Generally speaking,
the same measures adopted by the EU to halt the BT epidemics, seem to be adequate against the EHD as well. Vaccines
should be considered by vaccine manufacturers. The humoral immunity elicited by the killed vaccines is serotype
specific, and therefore, preventive measures should consider all nine serotypes. Priority should be given to the serotypes
already detected around the Mediterranean Basin, namely, 7 and 6 (formerly 318). It is important to recognize that the
vector-borne diseases that Israel has recently experienced could also spread to the European continent.
Key-words
Epizootic Hemorrhagic Disease (EHD), EHD-virus, Orbiviruses
References
Bread S et al. - Outbreak of epizootic hemorrhagic disease on the island of Reunion. Vet Rec, 2004, 155:422-423.
Brenner J et al. - Multiple serotypes of bluetongue virus infecting sheep and cattle in Israel. Emerging Infectious
Diseases DOI, 2010, 10.3201/eid1612.100239.
Brenner J et al. - Multiple serotypes of Bluetongue virus in Israel: Unique features of the disease in dairy cattle. Vet
Rec, (2011, submitted)
Brenner J et al. - Serological evidence for reactivity of Akabane virus in the northern valleys of Israel in 2001. J Vet
Med Sci, 2004a, 66:441-443.
Brenner J et al. - Serological and clinical evidence for reactivity of arboviral teratogenic Simbu sero-group infection in
Israel: 2001/2003 episode(s). Veterinaria Italiana, 2004b, 40:113-123.
Brenner J, Malkinson M, Yadin H. - Application of various diagnostic procedures to epidemiological situations
encountered during arboviral infection. Veterinaria Italiana, 2004c, 40:567-571.
Campbell CH, Barber TL, Jochim MM - Antigenic relationship of Ibaraki, bluetongue, and epizootic hemorrhagic
viruses. Vet Microbiol, 1978, 3:15-22.
Darpel KE et al. - Clinical signs and pathology shown by British sheep and cattle infected with Bluetongue virus
serotype 8 derived from the 2006 outbreak in northern Europe. Vet Rec, 2007, 161:253-261.
Elbers ARW et al. - Performance of clinical signs to detect bluetongue virus serotype 8 outbreaks in cattle and sheep
during the 2006-epidemic in the Netherlands. Vet Microbiol, 2008a, 129:156-162.
Elbers ARW et al. - Field observations during the bluetongue serotype 8 epidemic in 2006. I. Detection of first
outbreaks and clinical signs in sheep and cattle in Belgium, France and the Netherlands. Preventive Vet Med, 2008b,
87:21-30.
Elbers ARW et al. - Field observations during the Bluetongue serotype 8 epidemic in 2006. II. Morbidity and mortality
rate, case fatality and clinical recovery in sheep and cattle in the Netherlands. Preventive Vet Med, 2008c, 87:31-40.
Elbers ARW et al. - Epidemiologic characteristics of bluetongue virus serotype 8 laboratory-confirmed outbreaks in
The Netherlands in 2007 and a comparison with the situation in 2006. Preventive Vet Med, 2009, 92:1-8.
Eschbaumer M et al. - Emergence of bluetongue virus serotype 6 in Europe - German field data and experimental
infection of cattle. Vet Microbiol, 2010, 143:189-195.
Goto M - Pathological studies of the so-called bovine influenza. I. On the changes in the visceral organs. Japanese J Vet
Sci, 1959, 21:123-129 (In Japanese)
Inaba Y, Ishii S, Omori T - Bluetongue-like disease in Japan, 1966.
Bulletin de l’Office International des Epizooties 66:329-340.
Inaba Y - Ibaraki disease and its relationship to bluetongue. Aust Vet J, 1975, 52:1978-1985.
Kalmar E, Peleg BA, Savir D - Arthrogryposis-hydraencephaly syndrome in newborn cattle, sheep and goats serological survey for antibodies against the Akabane virus. Israeli J Vet Med, 1975, 32:47-54.
Kedmi L et al. -Assessment of the productivity effects associated with epizootic hemorrhagic disease in dairy herds. J
Dairy Sci, 2010, 93:2486-2495.
Maclachlan NJ, Osburn BI - Epizootic hemorrhagic disease of deer. In: Infectious Disease of Livestock 2ND edition,
2004:1227-1230. Editor, COETZER, J.A.W. & TUSTIN. R.C. Oxford South Africa.
Markusfeld-Nir O, Mayer E - An arthrogryposis/hydranencephaly syndrome in calves in Israel 1969/70 –
epidemiological and clinical aspects. Israeli J Vet Med Sci, 1971, 28:51-61.
Mellor PS, Boorman J, Baylis M - Culicoides biting midges: their role as arbovirus vectors. Annual Review of
Entomology, 2000, 45:307-340.
Mertens PPC et al. - Design of primers and use of RT-PCR assays for typing European bluetongue virus isolates:
differentiation of field and vaccine strains. J Gen Virol, 2007, 88:2811-2823
Mueller-Doblies U et al. - Clinical signs and pathology shown by British sheep and cattle infected with bluetongue virus
serotype 8 derived from the 2006 outbreak in northern Europe. Vet Rec, 2007, 161:253-261.
Nara Pereira Em, Iwata H, Inoue T - The complete nucleotide sequence of segment L2 of Ibaraki virus encoding for the
antigen recognized by neutralizing antibodies. J Vet Med Sci, 2000, 62:317-321.
Omori T - Bluetongue-like disease in Japan. Bull OIE, 1961, 55:1109-1117.
Omori T et al. - Ibaraki virus, an agent of epizootic disease of cattle resembling bluetongue. I. Epidemiologic, clinical
and pathologic observations and experimental transmission to calves. Japanese J Microbiol, 1969a, 13:139-167.
Omori T et al. - Ibaraki virus, an agent of epizootic disease of cattle resembling bluetongue. II. Isolation of the virus in
bovine cell culture. Japanese J Microbiol, 1969b, 13:159-168.
Prestwood AK et al. - The 1971 outbreak of hemorrhagic disease among white-tailed deer of the southeastern United
States. J Wildlife Dis, 1974, 10:217-224.
Purse BV et al. - Climate change and the recent emergence of bluetongue in Europe. Nature Rev Microbiol, 2005,
3:171-18.1
Radostits OM et al. - Hemorrhagic diseases. In Veterinary Medicine. A Textbook of the Diseases of Cattle, Sheep, Pigs,
Goats and Horses. London, W. B. Saunders, 2007:1305.
Simshoni A - An epizootic Akabane disease in bovines, ovines and caprines in Israel, 1969-70: epidemiological
assessment. Acta Morphologica Acad Sci Hungarica, 1980, 28:197-199.
Shope Er, Macnamara G, Mangold R - Deer mortality - epizootic hemorrhagic disease of deer. New Jersey Outdoor,
1955, 6:17.
Stram Y et al. - Akabane virus in Israel: a new virus lineage. Virus Res, 2004, 104:93-97.
Thiry E et al. - Bluetongue in northern Europe. Vet Rec, 2006, 159:327.
Temizel EM et al. -Epizootic hemorrhagic disease in cattle, Western Turkey. Emerging Infect Dis, 2009, 15:317-319.
Toussaint JF et al. - Bluetongue in northern Europe. Vet Rec, 2006, 159:327.
Yadin H et al. - A large-scale outbreak of bovine hemorrhagic disease in Israel. Israel J Vet Med, 2007a, 62:28-29.
Yadin H et al. - Epizootic haemorrhagic disease virus type 7 infection in cattle in Israel. Vet Rec, 2008, 162:53-56.
Yeruham I et al. - Bovine ephemeral fever in a dairy cattle herd in the Jordan Valley. Vet Rec, 2005, 156:284-286.
Yeruham I et al. - Epidemiological investigation of bovine ephemeral fever outbreaks in Israel. Vet Med Int DOI:
10.4061/2010/29054, 2010.
Bovine neonatal pancytopenia
G. FOUCRAS - Université de Toulouse, INP, ENVT, UMR 1225, IHAP, Toulouse, France
[email protected]
Bovine Leptospirosis in Europe
W. A. ELLIS - Killinchy, Newtownards, UK
[email protected]
Introduction
Bovine leptospirosis is a worldwide zoonotic disease caused by spirochaetes of the genus Leptospira. It can cause
serious economic loss primarily through reproductive wastage, particularly in the dairy industry. Infection by the cattle
maintained strain - serovar Hardjo - has characteristics which sets it apart from the traditional view of animal
leptospirosis:
• it has a major tropism for genital tract, with often poor renal colonisation and urinary excretion,
• the organisms are excellent parasites, which do little damage to the host except under certain circumstances,
• immunity is very different to the conventional view based on incidental infections in experimentally infected
laboratory rodents and companion animals,
• it is primarily a disease of intensification,
• it poses particular problems for the diagnostician.
Effective monovalent vaccines for the control of serovar Hardjo have been available in the UK and Ireland since the
1980’s but with their recent more general availability in a number of mainland European countries it is perhaps timely
to review this infection of cattle, its diagnosis, treatment and control.
The organism
The genus Leptospira includes both saprophytic and pathogenic species. The pathogenic family consists of 13
pathogenic species: L. alexanderi, L. alstonii, L. borgpetersenii, L. inadai, L. interrogans, L. fainei, L. kirschneri, L.
licerasiae, L. noguchi, L. santarosai, L. terpstrae, L. weilii, L. wolffii, with more than 260 serovars.
Strains belonging to only the L. borgpetersenii, L. interrogans and L. kirschneri are found in Europe.
At the subspecies level, serovar classification of Leptospira is still widely used as it facilitates sero-diagnostic,
epidemiology and prevalence studies. It is based on the expression of the surface-exposed epitopes in a mosaic of the
lipopolysaccharide (LPS) antigens, while the specificity of these epitopes depends on their sugar composition and
orientation.
Leptospires have a typical double membrane structure in which the cytoplasmic membrane and peptidoglycan cell wall
are closely associated and are overlaid by an outer membrane. Within the outer membrane, the lipopolysaccharide
(LPS) constitutes the main antigen for Leptospira. In addition to LPS, structural and functional proteins form part of the
Leptospiral outer membrane. A large proportion of such proteins are lipoproteins with relative abundance on the cell
surface: LipL32 > LipL21 > LipL41.
The LPS antigens and the outer membrane proteins play a role as immunogens but their relative importance is remains
poorly understood.
Epidemiology
The epidemiology of bovine leptospirosis is potentially very complicated, since cattle can potentially be infected by any
of the pathogenic serovars. Fortunately, only a small number of serovars will be endemic in any particular region or
country. Furthermore, leptospirosis is a disease that shows a natural nidality and each serovar tends to be maintained in
specific-maintenance hosts. Therefore, in any region of Europe, cattle will be infected by serovars maintained by cattle
or by serovars maintained by other animal species present in that region. The relative importance of these incidental
infections is determined by the opportunity that prevailing social, management, and environmental factors provide for
contact and transmission of leptospires from other species to cattle.
Cattle act as a maintenance host for serovar Hardjo worldwide. In addition, there is evidence that serovar Hardjo may
be adapting to sheep and farmed red deer. Experimental data would suggest that goats are susceptible to Hardjo
infection. Closely related strains have been isolated from milking buffalo in southern Italy.
Incidental infections of cattle vary from region to region within Europe. While serological and cultural evidence of
serovars Bratislava, Canicola, Icterohamorrhaegiae, Grippotyphosa and Mozdok infection have been reported disease
reports are rare and have been largely restricted to a small number of animals - usually young stock.
Two major genotypes of serovar Hardjo are found - L. interrogans serovar Hardjo (so called Hardjoprajitno) and L.
borgpetersenii serovar Hardjo (so called Hardjo Bovis). Both genotypes share major outer membrane anitigens and
cannot be distinguished by serological tests. L. borgpetersenii serovar Hardjo is responsible for most Hardjo infections
in cattle and strains of this type is have been used in major monovalent vaccines (Spirovac) used for the control of
bovine Hardjo infection. L. interrogans serovar Hardjo is a much more fastidious organism to grow and there fore
comments about it relative importance or otherwise have to be guarded: data from the 1980’s indicated it was more
likely to be involved in disease outbreaks but it would appear now to be uncommon. A strain belonging to this type is
also used for vaccine production (Leptavoid-H). Within these genotypes there is considerable genetic diversity, a
consequence of which is that different strains show different tissue trophisms and pathogenicity leading to differences
in or absence of clinical disease. Comparison of the L. interrogans serovar Icteroheamorrhagiae and L. borgpetersenii
serovar Hardjo genome sequences has shown that Hardjo is considerably smaller, having lost a lot of redundant housekeeping genes thought to be necessary for survival outwith the host resulting in its limited host range, shorter survival
times outwith the host and consequently being much more dependent on host-to-host transmission.
Hardjo is endemic in many major cattle producing countries eg USA, Australia, New Zealand, South America. The
situation in Europe in less well understood due to lack of recent reliable surveillance data. It is endemic in the UK and
Ireland, but the situation in mainland Europe is variable. A recent serological survey of 212 herds in France indicted
that 65% of herds showed evidence of recent infection, while in the UK 75% of dairy herds in Wales had evidence of
infection. Bulk milk sample surveys of herds in Germany, Spain and Italy have shown infected herd prevalences of
36%, 20% and 5% respectively. Infection in the Netherlands was high in the 1980’s but thanks to a control scheme is no
almost absent. The limited data from Scandanavia would indicate it is either absent or present only at very low levels.
As well as factors which are inherent to the infecting strain, there are other factors which influence the extent and nature
of clinical Hardjo infection, especially animal population parameters. For clinical Hardjo to occur, there must be a
source of infection: direct or indirect contact with a persistent carrier animal and a group of sexually mature susceptible
cows. Major risk factors are: an open herd policy, with bulls being bought in or shared by neighbouring farms, bought
in females, co-grazing with sheep, watercourses with up-stream cattle and access to other cattle.
Pathogenesis and clinical disease
An understanding of pathogenesis is fundamental to an appreciation of the clinical expression of Hardjo infection, its
transmission, immunity, diagnosis and control.
Infection is thought to occur mainly through the mucous membranes of the eye, nose and genital tract. In the week
following infection a bacteraemia develops at which time leptospires may be detected in blood and milk. This phase is
usually subclinical but can result in agalactia.
Agalactia is characterised by a sudden drop iin milk production, a soft flabby udder, all four quarters are equally
affected, the milk has a colostrum like consistency, a high cell count and is apparently sterile when examined for
mastitis causing organisms. Affected cows may be pyrexic. Cows in early to mid lactation return to full milk production
over a 10-14 day period, with or without treatment, and appear to compensate for that loss of production over the
remainder of the lactation, however cows in later lactation do not appear to have a compensatory production response
and those affected late in lactation may dry-off prematurely.
Bacteraemia ends with the development of a humoral immune response. This humoral response is largely to LPS. There
is no significant cell mediated response. Figure 1 illustrates the serological response to infection as determined by the
microscopic agglutination test (MAT), while figure 2 compares the MAT response with serum IgG ELISA and milk
IgG ELISA responses.
Figure 1: Serological response to infection
Figure 2: Serological response in an experimentally infected heifer
Organisms localise and persist in the proximal renal tubules where they can persist for the life time of the animal.
Associated with renal infection a mild focal interstitial nephritis develops.
They also localise and persist in the male and female genital tracts. The genital tract is as commonly infected as the
kidney. Reproductive wastage associated with genital infection in the cow is the major cause of economic loss
associated with Hardjo infection. In the cycling cow persistent infectionof the oviduct can occur and there may be
invasion of the embryo. In the case of the pregnant cow a number of things may happen. Infection of the trophectoderm
occurs with no infection of the foetus (common). The foetus may become infected and if there is no functional adrenal
cortex the foetus may become persistently infected with no clinical consequences. Infection of the foetus in late
gestation can result in abortion, stillbirth or the birth of weak calves. This usually occurs some 4 to 12 weeks after initial
infection of the cow. Following expulsion of an infected foetus, leptospires may be found in vaginal discharge for up to
14 days. Infertility has now become an established facet of Hardjo infection. This is based on significantly higher
conception rates in Hardjo negative animals in infected herd, when compared with infected animals and split herd
vaccination trials in the year following Hardjo infection when significant improvements have been observed in
vaccinated cattle compared to unvaccinated controls and consequently much lower culling rates in the vaccinates when
compared with the controls.
Diagnosis
Diagnosis of agalactia is based on the the clinical features and a diagnostic rise in MA titres. Diagnosis of Hardjo
abortion is ideally based on the demonstration of leptospires in fetal tissues by immunofluorescence but frequently it
has to be based on herd serology, showing evidence of recent infection in affected groups and the absence of other
abortifacient agents. The diagnosis of infertility is often done retrospectively following a vaccination programme.
Bulk milk ELISA’s (Linodee or Prionics) are widely used as herd tests to show the absence or presence of infection in
herds and for monitoring herd status. They are also very useful educational tools for making clients aware of the status
of their herd and introducing them to considering control programmes.
Treatment
When faced with a herd outbreak of agalactia, vaccination is the tool of choice and brings about a rapid response. The
use of antibiotics to treat individual affected animals has limited use, at best hastening return to full milk production by
only 1 - 2 days. This limited value must be balanced against the cost of the antibiotics and the problems of milk
withdrawal times.
In the face of an abortion outbreak, vaccination is the prime method of control. However vaccination will not prevent
abortion in all cases as placental infection may have already taken place. Farmers need to be aware that abortions could
continue to occur for a further 3 months.
Vaccination and treatment will stop abortion outbreaks but again the use of antibiotics must be balance against the loss
of milk sales due to withdrawal times. This is usually the best option for those pregnant animals which have already
dried off.
Control
Control is based on the interruption of direct and indirect transmission, however direct transmission appears to be most
important as this leptospire has limited survival outwith the host. That means preventing sexual transmission, contact
with the products of abortion and vertical transmission. Avoid sweeper bulls or shared bulls and preferably move to AI.
There are various reasons for considering a control programme. These include the obvious reason of preventing clinical
disease and economic loss in cattle, but also the need to satisfy health and safety considerations by reducing the risk of
transmission to employees. Pedigree herds with the opportunity to sell bulls to AI stations also need to eliminate
infection from their herds. Control programmes also provide opportunities for generating income for veterinary
practices through the provision of vaccines and herd monitoring regimes. The type of control programme is determined
by what the desired outcome is: is it to establish an immune population or to establish a population completely free
from infection ?
Vaccination is the major control tool and it is the only tool required by most commercial farmers, whose requirement is
to have an immune population. Antibiotic therapy can be an important tool as an effective quarantine treatment for
preventing the introduction of infection into clean herds. It also has a role in herds going for eradication where there is a
need to reduce the level of infection in a herd. Identification and removal of infected animals is a major tool used in the
control of other infectious diseases but has no role in Hardjo control as there is no test or combination of tests which
will reliably identify infected animals.
Modern monovalent vaccines are killed bacterins which have been shown to give good microbiological and clinical
protection for up to 12 months and therefore fit in with an annual vaccination regime. In contrast to the LPS humoral
immune response induced by natural infection these vaccines also induce a strong TH1 CMI response which peaks
about 90 to 120 days post vaccination. CD4, CD8 and %'T cells are the major components of this response. This
response is to a number of outer membrane proteins. This is in marked contrast to the older multivalent vaccines which
have been shown to provide little protection when challenged by a natural route and do not induce a TH1 response. A
lot work has been done on possible recombinant vaccines but critical analysis of the results gives little indication of
progress on that approach.
Management of risk factors an important component of control programmes where eradication is the objective.
There are several options with various permutations for control.
Option 1 is annual vaccination. This is the most appropriate programme for the commercial farmer. It comes with a
health warning, - "if you start on a vaccination programme stay on it". Farmers are tempted to stop vaccination when
there are no apparent problems and cessation is seen as a means of cost cutting. They may by this time have a herd with
no active infection and after several years of no vaccuination will have a fully susceptible herd and may be at greater
risk than if they had not vaccinated in the first instance. If they start on a vaccination programme they must stay on it.
Option 2 is for farms who can establish freedom from infection by a number of clear serological and who have a
rigorous policy for controlling the risk factors and whose commercial interests are in selling high health status animals
to other similar farms or AI centres. There are voluntary registration schemes for such herds in a number of countries eg
CHeCS. They re require ongoing monitoring for freedom from infection to maintain registration.
Summary
• serovar Hardjo is maintained by cattle,
• sero-prevalences within Europe are highly variable,
• clinical impact is on the pregnant and or lactating dairy cow,
• vaccination is the most practical method of control for most commercial farmers,
• serological testing, especially milk ELISA’s are important in monitoring control programmes and as educational
tools.
The changing face of digital dermatitis - "Mortellaro's disease"
R. BLOWEY - FRCVS, Wood Veterinary Group, Gloucester, UK
[email protected]
Introduction
Digital Dermatitis (DD), also known as Mortellaro, Strawberry Foot Rot or, in its more chronic form, Hairy Warts, is a
bacterial infection of the epidermal skin of the heel bulb. The disease was first reported in Italy by Cheli & Mortellaro
(1974) and now has a worldwide distribution, accounting for around 20% of all lame cows. It was first reported in the
UK in 1988 (Blowey & Sharp, 1988). More recently digital dermatitis accounted for 17% of 750 cases of lameness seen
in a study reported by Hedges et al. (2001) or 12 cases per 100 cows per year from a total of 69 cases/100 cows. This
was equal in incidence to sole ulcers and white line defects.
Although enormous research efforts over the past 25 years has led to an increase in our understanding of lameness, the
incidence has not declined significantly, and remains around 50 cases per 100 cows per year.. Presumably this is
because the factors causing lameness (increasing yields, higher levels of feeding, larger herd size etc.) have increased
more rapidly than the control measures that have been applied. Another reason for the increase in lameness over the
past 15 years is of course the advent of digital dermatitis.
The lesions
Typically digital dermatitis is seen as a red, raw area of epidermitis, surprisingly painful to the touch, and with a
characteristic foul odour. Lesions are most commonly sited on the skin just between the bulbs of the heels and the
reservoir of infection is thought to persist in the interdigital pouch, which is the space between the claws towards the
heel. Lesions may also be seen at other sites such as the skin of the interdigital cleft, at the front of the interdigital cleft,
and sometimes under running the sole or even as a secondary infection on a sole ulcer or white line lesion with exposed
corium. If lesions occur on the anterior coronary band they can totally disrupt wall horn formation and lead to a vertical
fissure. Many cows with vertical fissures never recover because an osteitis develops on the underlying pedal bone, and
the excess new bone formed forces the fissure apart. The North American "hairy wart" form of digital dermatitis is
rarely seen in the UK. This occurs in chronic, longstanding infections, because epidermal proliferation is a common
response to the causative organism. Using an immunoperoxidase procedure and monoclonal antibodies, UK work has
identified the presence of the specific DD organism in necrotic anterior udder lesions (Read et al., 2011). Of much
greater importance, Evans et al. (2011) have shown that DD is involved in, and possibly the cause of, a range of hoof
lesions, including non healing sole ulcers, wall ulcers and toe necrosis. It would appear that the latter lesion especially
has increased over the past 5 plus years, and is now an important factor in the need to foot bath on a regular basis.
Aetiology
Digital dermatitis is a bacterial infection caused by a spirochaete, most probably a Treponeme. Initial studies suggested
that Borrelia burgdorferi, the cause of Lyme disease might be implicated, and although calves seroconvert at the same
time as lesions appear, the correlation is by no means specific. Evans et al. (2008) have named three organisms that they
consider to be involved, namely T. phagedenis, T. medium and T. denticola. A strong association exists between
F. necrophorum and treponemes in human oral infections (Choi, 1997), and it may well be that a synergy exists in the
pathogenesis of the disease. One strain of the organism is thought to be sheep associated and may be implicated in the
syndrome of contagious ovine digital dermatitis (CODD) (Dhawi et al., 2005)
Damp conditions are important for the proliferation of the organism. Experimental transmission of DD (Read &
Walker, 1996) has only been achieved by soaking the leg with water daily for 8 days and then applying fresh DD
exudate onto scarified skin using gauze. Lesions of DD developed within 14 days, whereas no DD developed on dry
skin even after 90 days. This shows the extreme importance of wet environmental conditions in the development of the
condition.
Epidemiology
Laven (1999) established a method whereby a large number of cows could be rapidly screened for digital dermatitis
without having to lift the feet. This was achieved using a boroscope, a rigid fibre optic device with a light source at its
tip. The tip was placed just behind the heel and this provided the operator with a good view of the surrounding area
without having to lift the foot. Although adequate for "typical" heel lesions of digital dermatitis, lesions in the
interdigital cleft and on the anterior coronary band would be missed.
Immunity
An initial hypothesis proposed that exposure of heifers to digital dermatitis prior to calving might provide a degree of
immunity and might prevent the development of lameness later in lactation. Laven (1999) carried out a total of 1810
examinations on 328 cows in different housing systems and at different stages of lactation. Approximately 41% of cows
had lesions of varying severity, and of these, 66% of cows had lesions in both hind feet. It would therefore appear that if
a cow was susceptible to DD she was more likely to develop lesions on both hind feet, and this immediately suggested
that immunity was not of major importance in preventing the disease. Conversely, there were a proportion of cows that
never developed DD, even in the high prevalence group. This suggested that either some cows have an innate immunity,
or that the conformation of their foot and/or their behavioural pattern is such that were not exposed to the same level of
contamination. In a genomic comparison, Scholey et al. (2011) showed that resistance was determined by SNP’s (single
nucleotide polymorphisms) at specific loci, including site 42 mega bite on chromosome 26.
Housing systems
In a comparison of housing systems (Laven, 1999), cows in cubicles had 1.6 times more lesions than cows housed in
straw yards, and even when lesions did occur, straw yard cows had much less severe lesions. In addition cows in
cubicles with automatic scrapers had 1.2 times more lesions than cows in cubicles of the same design but without
automatic scrapers. It has been suggested that might occur:
• because the scrapers pull a "wave" of slurry through the building and this increases the contamination of cows’
legs,
• because it is the corrosive effect of the mixture of urine and faeces that is particularly important in the
pathogenesis of the disease, and,
• because the scraper removes the layer of cubicle bedding in the passage that would otherwise lead to drier
conditions.
As there is a lower incidence of DD in straw yards, an additional preventive measure would be to house freshly calved
heifers in straw yards for the critical first 2 - 4 weeks after calving. This would also have a beneficial effect on the
prevention of hoof lesions.
Factors increasing the degree of exposure to slurry will also be important. For example excess standing (from slow
milking systems, inadequate cubicle numbers, inadequate loafing space, or inadequate feeding space) will lead to
increased slurry and increased exposure times.
The influence of calving
In a biotin intervention study involving 1109 cows years on trial, where every lame cow was examined, photographed
and recorded by a vet, Blowey et al. (2004), showed a marked increase in proportion of the infectious causes of
lameness, digital dermatitis and foul, in the first month after calving. Digital dermatitis continued to increase until the
4th month, with heifers especially affected. This is a common finding reported anecdotally by dairy farmers. The post
calving increase in digital dermatitis is likely to be associated with two factors, namely immunosuppression and
increased standing and exposure to slurry. It is well known that there is a marked immune suppression in all
periparturient cows, and this immune suppression is likely to predispose to an increase in digital dermatitis and foul.
The foot of the post partum animal will also have increased exposure to slurry. This will be due to longer periods of
standing to be milked (and heifers are often last into the parlour), standing to feed (heifers again are often the last to be
able to access the feed trough), standing waiting for a cubicle or learning to use a cubicle, and possibly overall concern
about entering buildings with blind ending passages where they may feel trapped. This marked increase in DD and foul
in the postpartum animal has important implications for the control of these diseases. Clearly hoof and environmental
hygiene is important in the post partum period. In addition, routine preventive foot bathing should clearly start in the
transition group, ideally before the onset of the period of immune suppression.
The importance of "open" lesions
It is clearly easier to prevent the development of DD lesions than to control the "open sores" of classic DD. A
significant prevalence of raw "open" DD lesions in a herd must act as a source of infection for other cows in the herd in
the same way that a Staph aureus carrier is a major mastitis risk to other cows. As such, affected cows should be treated
(eg by bandaging a topical dressing in place for 2-3 days) as a matter of urgency to reduce the spread of infection. This
is often not done.
Treatment and prevention
Treatment
Individual cases are treated by thorough cleaning of the lesion followed by topical application of antibiotic. Anecdotally
use of an intramammary mastitis tube on a well cleaned lesion works well, and there are many published reports of
copper and other products having a beneficial effect, (Holzhauer et al., 2011). Long acting parenteral therapy, eg
ceftiofur, which has a nil milk withhold, has been advocated for the recently reported non healing hoof lesions such as
toe necrosis (Blowey et al., 2011).
Prevention
Prevention is based on maintaining the housing and general environment as clean and dry as possible (Barker et al.,
2009) and by whole herd footbaths through solutions of disinfectant.
Housing
Cleanliness of housing, and especially of the floor surfaces, will be dependant on a range of factors, many of which
were discussed earlier. Buildings should be well drained to remove excess floor water, and well ventilated, with good
air flow, to take moisture out of the atmosphere. Wide passageways in cubicle houses are of great benefit, as is the
provision of additional space and a lower stocking density in general.
Foot bathing
As discussed above, dry cows have mild lesions of digital dermatitis, and with the immune suppression associated with
calving, these proliferate to produce lameness 4-8 weeks into lactation. The best form of digital dermatitis control is
therefore a proactive footbath prepartum and in early lactation to prevent these mild lesions from developing. This
works well, with many UK farmers now controlling the disease by regular disinfectant foot bathing. The frequency of
bathing will vary with the severity of the challenge (viz depending on environmental conditions) but a common routine
for continual confinement herds is now twice daily every day. The previous reactive approach, namely only foot bathing
when lesions had developed sufficiently severely to produce lameness, was clearly illogical, because this allowed
lesions to develop to such an extent that total control was almost impossible. Common disinfectants include formalin
(usually at 4 - 5%) copper sulphate (4%), zinc sulphate and a range of proprietary products although it is likely that any
disinfectant would be effective. Although unpleasant to handle and a potential carcinogen - and hence its use has been
banned in some countries - formalin is rapidly degraded in the environment and hence can be emptied into the slurry
every day. Copper is more pleasant to handle, but it can accumulate in the environment and copper poisoning is
becoming more of an issue for dairy cows.
Foot baths should not be too deep - 70 to 80mm is ample - they should not be used close to the exit of the milking
parlour, as this may impede cow flow. If formalin is used, the footbath should not be positioned where fumes are
detectable in the parlour or where there are raw open lesions of digital dermatitis present due to pain. However, use of
formalin has been reported to control interdigital skin hyperplasia.
Foot baths should be comfortable to walk through and cows should feel a firm footing beneath. Baths with high ridges
in the base (suggested to splay the claws) will be uncomfortable to walk on and could lead to bruising of the hoof, and
as such are not recommended. If plastic baths are used they should be placed on a good level and firm surface.
Footbaths with a separate left and right side joined by hoops are not popular with cows as they alter their natural gait.
An easily cleaned and drained concrete bath is ideal.
References
Barker ZE et al. - Risk factors for increased rates of sole ulcers, white line disease, and digital dermatitis in dairy cattle
from twenty-seven farms in England and Wales. J Dairy Sci, 2009, 92:1971-8.
Blowey RW & Sharp MH - Digital Dermatitis in a dairy herd, Vet Rec, 1988, 122:505.
Blowey RW et al. - The effects of season and stage of lactation on lameness in 900 dairy cows, Proc Int Ruminant Digit
Symposium, Maribor 2004, p. 43.
Blowey RW, Evans NJ, Carter S - The involvement of digital dermatitis Treponemes in non – healing bovine hoof
lesions. Proc International Ruminant Digit Symposium, Rotorua NZ, March 2011.
Cheli R. & Mortellaro C - Digital Dermatitis in cattle. In Proceedings of the 8th International Conference on Diseases of
Cattle. Milan, 1974:208-213.
Choi BK et al. - Spirochetes from digital dermatitis lesions in cattle are closely related to treponemes associated with
human periodontitis. International Journal of Systematic Bacteriology, 1997, 47:175-181.
Dhawi A et al. - Bovine digital dermatitis and severe virulent ovine foot rot: A common spirochaetal pathogenesis. Vet
J, 2005, 169:232-41.
Evans NJ et al. - The association of bovine digital dermatitis treponemes with a range of ‘non healing’ bovine hoof
disorders. Vet Rec, 2011, 168:214.
Evans NJ et al. - Three unique groups of spirochetes isolated from digital dermatitis lesions in UK cattle. Vet Microbiol,
2008, 130:141-150.
Hedges VJ et al. - A longitudinal field trial of the effect of biotin supplementation on lameness in dairy cows. J Dairy
Sci, 2001, 84:1969-1975.
Holzhauer M et al. - Clinical trial on the curative effect of intra Hoof-Fit Gel an Digital dermatitis in Proc International
Ruminant Digit Symposium, Rotorua NZ, March 2011.
Laven R - The Environment and digital dermatitis. Cattle Practice, 1999, 7:349-355.
Read DH &Walker RL - Experimental transmission of papillomatous digital dermatitis (Footwarts) in cattle. Vet Pathol,
1996, 33:607.
Read DH et al. - Is digital dermatitis related to ulcerative mammary dermatitis of cattle? Proc International Ruminant
Digit Symposium, Rotorua NZ, March 2011.
Scholey R et al. - Genetic loci associated with digital dermatitis in UK Holsteins. Proc International Ruminant Digit
Symposium, Rotorua NZ, March 2011.
Abstract
Digital dermatitis and its associated syndromes is a common cause of lameness in dairy cows. It is a bacterial infection
of the epidermis primarily affecting the skin above the bulbs of the heel. Treponemes including T. medium, T.
phagedenis and T. denticola have been implicated. The prevalence of digital dermatitis is significantly affected by
environmental management, with higher rates wet conditions, for example in cubicle yards as opposed to straw yards,
and increased prevalence in automatically-scraped cubicles as opposed to tractor-scraped cubicles. Post partum
immunosuppression affects the severity of digital dermatitis, with lameness increasing significantly post partum and
peak levels occurring in the first 4 months post calving.
Much effort has been aimed at treatment, but treatment alone will not control dermatitis, just as treatment of mastitis
alone will not effectively control mastitis. Prevention is therefore essential. In addition to environmental factors, it is
proposed that the best form of digital dermatitis control is proactive foot bathing, including dry period and transition
cows. Foot bathing with disinfectant ideally needs to be regularly repeated, eg on a daily basis, to be effective. The
precise frequency required will depend on the level of environmental challenge.
POSTERS
Efficacy of Paromomycin in preventing cryptosporidiosis in naturally infected neonatal calves
BARBERIO A. [email protected]
A. Barberio, M. Badan, S. Bonamico, Istituto Zooprofilattico Sperimentale delle Venezie, Vicenza, Italy
G. Simonato, M. Mancin, Istituto Zooprofilattico Sperimentale delle Venezie, Legnaro, Italy
The aim of this study is to describe the use of Paromomycin in preventing cryptosporidiosis in naturally infected
neonatal calves on a dairy farm with a high prevalence of infection. A randomized trial with naturally infected calves
was carried out in a dairy farm with 710 cattle. The cows were vaccinated against IBR, BVD, Clostridium perfringens
and calf scour agents. The calves, irrespective if males or female, were kept in individual pens till 28-30 days, and fed
with cow milk and calf starter. All the calves born from 01.12.2009 and 03.05.2010 were included in the trial, and
randomly assigned to one of these two groups: calves treated with 50 milligrams of Paromomycin/kg BW, administered
orally in milk for 7 days, and untreated control group. For the following 21 days each case of diarrhoea was recorded
and a faecal sample from diseased animals was taken; furthermore every week a samples of faeces was taken from each
calf, irrespective of scour presence. All the faecal samples were examined using a coproantigen-ELISA for Rotavirus,
Coronavirus, Cryptosporidium spp. and E. coli K99, and a modified Ziehl-Neelsen stain for Cryptosporidium spp.
Statistical analysis was performed using Z test to compare two independent proportions. A total of 101 calves were
included in the trial, 49 in treated group, and 52 in the control one. The most frequent infective agents identified in the
diarrhoeic calves were Rotavirus and Cryptosporidium spp, with 31 (38%) and 27 (33%) cases respectively. The
remaining 23 (29%) cases of diarrhoea recorded were negative to all the tests performed. The peak of scour cases (31%)
was recorded at the average age of 14 days. Paromomycin was shown to be effective (P<0.01) in reducing the onset of
diarrhoea in treated calves: the prevalence of scour associated with the identification of Cryptosporidium spp was 10%
in treated calves versus 38% of control group. Paromomycin was effective also in calves with mixed diarrhoea from
both Cryptosporidium spp and Rotavirus (P<0.01): in this case the prevalence of scour in treated animals were 4% and
in control group 19%.
Effect of a pour on ivermectin treatment on colostrum quality of multiparous suckling cows
BOUSQUET E. [email protected]
E. Bousquet, Virbac, France
N. Gaudout, Villaines la Juhel, France
C. Mage, Estivaux, France
F. Courouble, Epinac, France
B. Chataigner, LVD69, Lyon, France
The objective of this study was to test the effects of an endectocide treatment scheme of suckling cows from a herd
infected by digestive roundworms on parasitological and zootechnical parameters.
Seventy nine suckling cows from one herd were randomly allocated to a treated or a control group on D0 (December
2008). No roundworms treatment had been administered since previous calving. Treated group received a pour on
ivermectin treatment (Virbamec pour on, 0.5 mg ivermectin/kg, Virbac) on D0, at turn out (March 2009) and at housing
(December 2009). Individual coproscopic examinations were done on D0 and D35. Immunodiagnosis of fasciolosis was
performed by ELISA method from pooled sera on D0. Inclusion at herd level required fecal egg counts (FEC) positive
for digestive roundworms and negative diagnosis of fasciolosis, and Paramphistomum FEC below 100 eggs per g (epg)
at cow level. An individual standardized body condition score was recorded on D0, at turn out, in summer and at
housing in 2009. Individual serological diagnosis of Ostertagia was performed by ELISA method on 10 cows per group
on D0 and D35, at turn out and at housing in 2009. Colostrum was sampled on all cows during 2009 and 2010 calvings
for assay of G immunoglobulins by radial immunodiffusion.
Results
FEC ranged between 0 and 45 epg on D0. Reduction was complete on D35 only in treated group (P<0.05).
Coproculture revealed a majority of Ostertagia (94%) and 6% of Oesophagostomum larvae. Serum antibody
concentration against Ostertagia decreased from a mean optical density ratio of 0.5 on D0 to a mean value of 0.3 on
D35, then remained in the range of limited immunological reaction (0.2 to 0.4) without differences between groups.
Mean body condition score increased from a median value of 2.5 on D0 to 4 during 2009 summer then decreased to 3 at
housing (no differences between groups). Colostrum immunoglobulins mean concentration was higher in treated group
during 2010 calvings (120.5 g/l vs 92.2 g/l in control group, P<0.01). Thus endectocide treatment of adult suckling
cows may be valuable owing to its effect on colostrum quality.
Use of decoquinate: its influence on the growth of indoor Merinos lambs in Extremadura
HABELA M.
[email protected]
M. A. Habela, Universidad de Extremadura, Caceres, Spain
J.M. Carmona, Acorex Merida, Spain
M. Jimenez, Alpharma Valencia, Spain
A. Richard, Alpharma, France
Sub-clinical coccidiosis is responsible for poor growth.
Decoquinate works very early in the coccidia life cycle on the free forms of the parasite before lesions occur. It works
every day in feed ensuring a continuous protection while still allowing immunity to develop.
The purpose of this trial was to check if adding decoquinate to our suphonamides feed after weaning would be
responsible for better growth. Sulphonamides are known to be effective against coccidia when parasites are inside the
cells, consequently not working at the same place as decoquinate.
The feed consumption being lower for the first days, in order to ensure a dosage of 1 mg/kg BW, decoquinate content in
the feed was 40 ppm the first 15 days then 25 ppm for the following 16 days while Sufadiazin was 500 ppm added to
100 ppm of trimethoprim for the first 15 days only. The SD group received decoquinate + Sulphonamides the first 15
days then decoquinate alone for the following 17 days while the S group received Sulphonamides + trimethoprime for
the first 15 days.
66 male and female lambs born to multiparous ewes, were divided at weaning at 24 days of age in 2 groups. Body
weights were recorded at D 0, weaning at D 13, D 19 and D 32 (end of the trial). Oocyst counts were done from 6 lambs
from each group at the beginning and the end of the treatment period.
Lambs had an average weight of 3.5 kg at birth and 16.73 kg at 24 days for SD group and 16.09 kg for S group, the start
of the trial. Average final weights were 26.97 kg for SD and 25.39 kg for the S group(+.94 kg). The feed conversion
ratio was 3, 11 in the SD and 3, 18 in the S group.
None of the lamb suffered from clinical sign of coccidiosis.
The average Oocyst shedding was low in both group at the start of the trial and higher at the end.
These results confirm that decoquinate increases growth.
Dairy cow mortalities due to babesiosis and anaplasmosis in Sudan
IBRAHIM A.
[email protected]
A. Ibrahim, S. Lazim, University of Bahr El Ghazal, Sudan
D. Geysen, Institute of Tropical Medicine, Antwerp, Belgium
Tick-borne diseases are major constraints to livestock development in the Sudan. The present paper reports the results
of a study on blood parasites in two dairy farms in Khartoum State. Sharp decrease in milk yield, recumbency, as well
as mortality in adult milking cows was encountered in these dairy farms. A total of 96 cattle (61 from Shigla and 35
from Soba area) were examined. These consisted of 75 cows and heifers over 1year old and 21 calves under 1 year.
Analysis of 96 blood smears revealed 47 samples (49%) positive for blood parasites. Thirty nine (83%) of the positive
cases were adult animals and the rest (17.0%) were young calves. The majority of adult cows was infected with
Theileria spp. (33.3%) and with Anaplasma spp. (28.2%) or had mixed infections (33.3%). Only 5% were positive for
Babesia spp. the mixed infections consisted of five cases with Theileria and Anaplasma spp. and eight cases with
Babesia and Anaplasma spp. Babesia bigemina was molecularly confirmed in 3 randomly selected cases using PCRRFLP. Infections in the young calves (8 cases) showed the same trend with only one case (12.5%) infected with
Babesia spp., two cases (25%) with Anaplasma spp. and three samples (37.5%) with Theileria spp. parasites. The
remaining two cases (25%) suffered from a mixed infection of Theileria and Anaplasma spp. Good post-treatment
progress regarding the general health of the sick animals was seen following babesiosis and anaplasmosis treatment.
Moreover, deaths in the adult cows stopped. It was concluded that despite the absence of Boophilus species ticks in the
investigated area, babesiosis and anaplasmosis should be considered as possible cause of death or economical losses in
dairy cattle in Khartoum State. Further investigation into the presence of tick vectors and the role of biting flies in this
respect is recommended.
Evaluation of botanic active compounds on the coccidian excretion and the growth
performance of Charolais suckling calves in Allier department (France)
MEDINA B.
[email protected]
B. Medina, F. Recoquillay, Phytosynthèse, Riom, France
P. Curat, St Etienne de Vic, France
Introduction
Respiratory disorders are one of the main health problems for calves caused by a large variety of pathogens (Schelcher
and Valarcher, 1999). The prevalence of these disorders is particularly high (6 to 17%) among suckling and non-weaned
calves (Assié et al., 2003). Recently, an epidemiologic study pointed out that 77% of suckling calves in Allier
department (03) were contaminated with coccidian oocysts in barns (Richard et al., 2006).
Therefore, the aim of this study was to evaluate the effect of a plant extracts based feed additive (PULMO Cx®, 95000
ppm of terpens, PHYTOSYNTHESE, Fr) on the performance of growth and coccidian excretion on Charolais suckling
calves.
Protocol
The evaluation of the additive was done through 2 consecutive studies. The first one was carried out on a total 42
animals during a 300-d period. In one group (CTL), animals were feed with a basal starter feed (18% CP) and received
2 treatments of vecoxan® (diclazuril, 1 ml/2.5 kg) at one month of age and at weaning whereas in the other group
(PULMO Cx®), animals received Vecoxan® only at one month of age and starter feed supplemented with 4 kg/ton of
PULMO Cx®. The second one was achieved on 18 calves: control group (CTL) received the same program as
mentioned before. In the PULMO Cx® group, no more vecoxan® was completed and substituted by a free access to
PULMO Cx® (20% mixing with clays) since the first week then in the starter feed (4 kg/ton) as previously. In each
study, live weight (LW) was recorded, a veterinary follow-up and faeces analysis were achieved on each animal.
Results
First study, weaning LW of animals from the PULMO Cx® is 16 kg heavier (P<0.1) than that one of the CTL group.
Second study, weaning LW of animals from the PULMO Cx® is 9 kg heavier (NS) than that one of the CTL group. In
both groups 5 animals excreted more than 100 epg of feces of coccidia. The max of excretion reached 2650 in CTL
group compared to 1140 epg of feces in PULMO Cx®.
Conclusion
Metaphylaxis program supplemented or completed only with plant extracts based feed additive affected positively
performance of growth of suckling Charolais calves.
Compared evaluation of two feed additives on the coccidian excretion and the growth
performance of Prim Holstein calves in Côte d'Armor department (France)
MEDINA B. [email protected]
B. Medina, J.M. Brault, Phytosynthèse, Riom, France
P. Douard, Yvignac, France
Introduction
For improving the profitability of its dairy farm, two strategies are possible for a farm's manager: to increase milk
production per milking cow or to decrease the cost of rearing of no-milking animals (calves and heifers for cattle turn
over) (increase ADG, decrease diseases and veterinary costs). In fact cost of rearing young dairy cattle represents till 10
to 40 ( of the production cost of 1000 kg of milk. Therefore, the aim of this study was to evaluate the effect of plant
extracts based feed additive (EMX®, 89600 ppm of terpens, PHYTOSYNTHESE, Fr) on the performance of growth and
general health's status on dairy calves.
Protocol
Two groups of 8 calves were conducted in parallel. Milk-replacer was fed till 77-90 days of life. A started feed was at
disposal (voluntary consumption 500 and 2000 g/d at 3 weeks and at weaning, respectively). In the CTL group, the
started feed was supplemented with Decoquinate premix (1%) (Deccox®), whereas in the EMX® group, both milkreplacer and starter feed were supplemented with the plant extracts based feed additive (EMX ®, 6 and 2 kg/T,
respectively). Live weight (LW), faecal coccidian's excretion and general health's status follow-up were recorded over
the trial.
Results
No animals died or suffered from pulmonary troubles.
Between 100 and 120 days of age, 50% (4 of 8) of the calves from the CTL group excreted coccidian ookysts compared
55% (5 of 9) in calves from EMX®.
In terms of growth performance (no significant differences): at weaning, average daily gain (ADG) of CTL group was
925 g/d compared to that one of EMX® 805 g/d.
From weaning to the end of the trial (between 4 and 5 months of age), ADG of CTL group decreased to 881 g/d
compared to that one of EMX® reaching 1000 g/d.
Conclusion
If the natural antibacterial activity of the EMX® additive did not present a total specificity against coccidia, the mode of
action of plant extracts should have a protective effect on epithelial cells of the small intestine explaining impact on
limiting symptoms of the disease and positive effects on growth performance.
Influence of decoquinate on the growth of Charolais calves at grass
RICHARD A. [email protected]
A. Richard, Alpharma, Verrières le Buisson, France
E. Charrier, Marcigny, France - L. Sgaralino, Misérieux, France
The purpose of this trial was to investigate whether adding decoquinate to feed provided to calves at pasture over the
summer would improve growth.
The trial was undertaken in a pedigree farm. As a routine for coccidiosis prevention on the farm, calves receive one
dose of toltrazuril the first few days of life and then diclazuril at turnout.
Decoquinate was incorporated in the feed to provide 0.5 mg/kg BW for 76 days.
40 pedigree males were divided at turnout in the spring into 4 groups according to age, BW, and phenotype: 2 groups of
"heavy" animals, one receiving decoquinate (Dx) 294 kg and the other a control (Ct) 302 kg, and 2 groups of "light"
animals, one receiving decoquinate (222 kg) and another control (218 kg). Body weights were recorded at D0 (12 July)
and D76 (26 September, the end of the trial). After 76 days’ decoquinate treatment, the "heavy" decoquinate group
weighed 466 kg whilst the controls weighed 454 kg, and the "light" decoquinate group weighed 375 kg whilst the
controls weighed 346 kg. So the decoquinate groups performed + 22.5*kg vs control.
Oocyst counts were done from on samples from 5 decoquinate-treated calves and 5 controls. The average oocyst
shedding was very low in both groups at the start of the trial, Dx: 48 oocysts per gramme and Ct: 255, and at the end of
the trial , Dc :171 and Ct :216. Eimeria bovis was recorded in 8 calves at D0 (3 for Dc group and 5 for Ct) and 4 calves
at D76 (2 for Dc group and 2 for Ct) both at alow level (maximum 915 for control at D76). Eimeria zuernii was
recorded in 2 calves at d 0. None of the calves showed clinical signs of coccidiosis before, during or after the trial.
These results confirm those of trials already performed on Charolais calves at grass: decoquinate increases growth even
when there are no clinical signs of coccidiosis.
Calculations and precautions for medicated feed
RICHARD A. [email protected]
A. Richard, Alpharma, Verrières le Buisson, France
D. Renney, Nimrod Veterinary Products Ltd, Cheltenham, England
H. Leibovich, Moshav Udim, Israel
For animals in a large group, collective treatment is easier than treating individuals. The same is true of a small group
requiring an extended course of treatment.
Ruminant farms usually lack equipment for medication of drinking water. Medicated feed is a useful alternative. It is
manufactured under veterinary prescription in registered mills which follow strict regulations concerning matters such
as traceability and homogenous mixing. The latter ensures a consistent daily intake of the active ingredient.
Having chosen a drug, the vet has to calculate an inclusion rate to provide the intended dose. To do so, he must take
account of the body weight of the animal, its feed intake and the concentration of the drug in the medicated premix For
example, 0.5 mg decoquinate/kg bodyweight for 80-kg calves implies that each calf needs 40 mg. If the daily feed
intake is 1 kg, the concentration of decoquinate must be 40 mg/kg. This is 40 g per ton, or 40 ppm. But use of undiluted
active ingredients is not permitted, because their inclusion rates would be too low for homogenous dispersion. An
authorized medicated premix must be used. Deccox is a 6% premix of decoquinate in several countries, so 700 g/ton
must be added to provide a concentration of 42 ppm (7 kg/ton in France where Deccox is a 0.6% premix).
Feed intake may vary considerably in the following situations, which must be taken into account to avoid underdosage:
•
•
•
•
•
•
•
•
young ruminants drinking milk,
feed transition especially after weaning,
stress, especially transportation stress,
restricted feed intake,
heat stress,
dilution of compound feed with home-grown cereals or protein concentrate,
intercurrent disease,
competition between animals.
Body weight also must be carefully evaluated. It is often under-estimated. If this is compounded by over-estimation of
feed intake, the consequence is dramatic underdosing.
In conclusion, medicated feed offers an easy and well-controlled means of prophylaxis or treatment of ruminants, but
some precautions must be observed in order to provide the intended dosage.
Evaluation of the comparative efficacy of moxidectin plus triclabendazole pour-on solution
against adult and immature liver fluke, Fasciola hepatica, in cattle
BATRAM D.
[email protected]
D. Batram, Pfizer Animal Health, Paris, France
T. Geurden, Pfizer Animal Health, Brussels, Belgium
C.D. Smothers, Pfizer Animal Health, Kalamazoo, USA
Objective
To evaluate the efficacy of a pour-on solution containing 0.5% w/v moxidectin plus 20% w/v triclabendazole against 4,
6 and 8 week old immature and 12 week old adult stage of the liver fluke (Fasciola hepatica) in cattle compared to
untreated controls and to treatment with commercially available formulations of 0.5% w/v ivermectin (IVM) plus 20%
w/v closantel pour-on or 1.0% w/v IVM plus 10% w/v clorsulon injection.
Procedures
Male, 3 to 4 month old, Holstein-Friesian calves (n=104), were allocated into 13 groups of 8 animals. All animals were
infected with 500 metacercariae of the liver fluke on Day 0. One group remained untreated. Four groups were treated
with either moxidectin plus triclabendazole pour-on at a dose rate of 0.1 ml/kg, respectively 4, 6, 8 or 12 weeks after
infection. Four groups were treated with IVM plus closantel pour-on at a dose rate of 0.1 ml/kg and a further four
groups were treated with ivermectin (IVM) plus clorsulon by subcutaneous injection at a dose rate of 0.02 ml/kg at the
same time points after infection. All animals were euthanised and necropsied for the recovery of flukes 14 to 15 weeks
after infection.
Results
The fluke count data indicated a very good establishment of infection in all animals after experimental infection (range
of 30 to 148 flukes per animal in the untreated group). Compared to the untreated controls, the moxidectin plus
triclabendazole treated animals yielded significantly (P<0.001) lower fluke counts at all treatment days. The efficacy
was 90.9%, 98.0%, 99.5% and 99.9% on weeks 4, 6, 8 and 12 after infection. By comparison, the efficacy in the IVM
plus closantel pour-on treated animals was 26.8%, 68.2%%, 90.6% and 99.3% on weeks 4, 6, 8 and 12 after infection.
The efficacy in the IVM plus clorsulon injection treated animals was 29.7%, 43.4%, 53.2%, and 99.2% on weeks on
weeks 4, 6, 8 and 12 after infection.
Conclusions
The results of the present study confirm the high efficacy of the moxidectin plus triclabendazole pour-on combination
against early immature, late immature and adult liver fluke in cattle. The treatment efficacies of IVM plus closantel
pour-on and IVM plus clorsulon injection are low against immature liver fluke. These differences in efficacy have
important implications for their use in liver fluke control programmes.
Evaluation of Norgestomet Crestar® in the reproduction performance of dairy cattle: case of
the area of the bass Kabylie
AYAD A.
[email protected]
A. Ayad, Y. Bellik, M. Iguer-Ouada, University A. Mira, Bejaia, Algeria
H. Benabarek, University M. Istambouli, Mascara, Algeria
Poor rates of estrus detection combined with low conception rates make management of reproduction in lactating dairy
cows a challenge in most dairy herds. Synchronisation of estrus has been developed to help farmers manage
reproduction more efficiently (Larson et al., 1992). The objective of our study was to evaluate the effectiveness of
Norgestomet Crestar® for synchronisation of estrus and the effect on pregnancy rate in cows. After a waiting period
(~ 90 days postpartum), Holstein-Frisian females (2-10 years old, 0-8 parity) from different dairy farm were
inseminated after detecting estrus (n=135). Females were allocated randomly to treated (n=69) or control (n=64)
groups. The treated animals received a Crestar® during 9-10 days, and artificial insemination (AI) at implant removal
(56-60 hours). Blood samples were collected from the coccegeal vein into a tube containing EDTA on Days 0, 21 and
30 after service. The plasma was immediately separated (1,500 x g for 15 min) and stored at -20°C until assayed. The
day of AI was considered as Day 0. Plasma progesterone (P4) and pregnancy-associated glycoprotein (PAG) levels
were determinate by RIA technique (Ayad et al., 2007; Lopez-Gatius et al., 2007). Females were classified as anestrus
if samples of P4 were <1 ng/ml and as cyclic if samples of P4 were "1 ng/ml. A cut-off value of 0.8 ng/ml PAG was
used to confirm pregnancy in the cow. The results of this experiment showed a higher rate of heat synchronisation in
treated group (94%) in comparison with control group (86%). Thirteen cows from treated and control group were
inseminated when progesterone concentrations were higher than 1.0 ng/ml (4 and 9, respectively). The plasma PAG
levels at Day 30 after AI were significantly lower in the treated group (7.13±2.29) compared to the control group
(8.75±2.16), and pregnancy rates were 26% (15/57) and 41% (18/43), respectively. In summary, this hormonal
treatment cannot be recommended as a general method for improving reproduction performance of dairy cattle in
northern Algeria. However, these data suggest that this hormonal protocol can be used to obtain satisfactory cyclic cow
rates and less incidence of incorrect timing of insemination.
Effect of caesarian section on aerobic bacteria of genital tracts of nubian goats in the Sudan
BADAWI M.
[email protected]
M. Badawi, Sudan University of Science and Technology, Khartoum, Sudan
S. Makawi, Faculty of Veteinary Medicine, Khartoum, Sudan
A total of 82 deep cervical swabs were collected from 10 post-parturient Nubian goats. Thirty eight (38) of these swabs
were from five Nubian goats which have kidded normally (control group) and 44 swabs were from post-parturient
Caesarean sectioned Nubian goats (CS group). Collection of the swabs started from the second day after kidding till the
goat came into the first observable heat. The number of isolates from the swabs taken from the two groups of goats
reached 104, belonging to 10 different genera. They included Bacillus spp, Bordetella spp, Corynebacterium spp,
Escherichia spp, Gemella spp, Klebsiella spp, Microccocus spp, Proteus spp, Staphylococcus spp and Streptococcus
spp. The organisms which were common between the two groups included: Bacillus cereus, Escherichia coli,
fergusonii, Staphylococcus chromogens and Streptococcus faecalis. It could be concluded from this study that, the most
likely, pathogenic organisms isolated during the post-partum period were more frequent in CS goats compared to those
goats kidded normally.
Comparison of the conception rates in synchronization methods: double OvSynch vs.
PreSynch-HeatSynch
DINI P. [email protected]
P. Dini, P. Mottaghian, M. Vafaei, Islamic Azad University, Tehran, Iran
M. F. Moghaddam, Islamic Azad University, Karaj, Iran
D. Nasseri, Committee of Veterinary Council of Islamic Republic of Iran
Estrus synchronization has become a routine reproductive management tool for dairy producers. Reproductive
performance has decreased over the last 25 years on dairy farms, and the lack of estrus detection or inaccurate detection
are major reasons for increased numbers of days open for the average cow. This study evaluated a new synchronization
method, using Ovsynch prior to the Ovsynch-timed AI protocol (Double Ovsynch) compared to Presynch-Heatsynch
protocol. Therefore Computer-based records of a large dairy farm (4400 cows) from October 2010 to the end of
December 2010 were investigated and 967 cows were selected. They were assigned to two groups on 35-40 days
postpartum: (1) Presynch-Heatsynch (n=641), two injections of PGF2alpha 14 days apart, followed by GnRH on day 0,
PGF2alpha on day 7, estradiol benzoate on day 8, and timed AI (TAI) 48 hours later (day 10); (2) Double-Ovsynch
(n=326), received GnRH, PGF2alpha 7 days later, and GnRH 2 days later, followed by the Ovsynch-timed AI protocol
7 days later. The beginning of PreSynch-HeatSynch and continuing of Double OvSynch were depended on the
existence of corpus luteum. Experimental design allowed artificial insemination to occur during the designed protocol
when estrus was detected. Pregnancy was diagnosed 39–45 days after TAI. In sum there was no significant difference
(P>0.05) in the conception rates between two protocols (44.8% in group 2 versus 49.1% in group 1), however there was
a significant difference (P<0.05) in the conception rates of the cows which inseminated following the estrus behavior in
two groups (61.4% in group 2 versus 49.1% in group 1). In addition there was a significant difference (P<0.05) among
the conception rates of TAI and AI following the estrus behavior in group 2 (Double-Ovsynch Protocol). Eventually, it
may be concluded that with regard to the reproductive management practices of dairy farms, each of these protocols
may be helpful to increase their reproductive performance.
Experience from using Heatime® activity monitoring for heat detection in Norwegian dairy
cows
GILLUND P.
[email protected]
P. Gillund, A. O. Refsdal, Geno, Hamar, Norway
R. T. Garmo, BioKapital, Hamar, Norway
Efficacy of Heatime® heat detection system was investigated during 95 estrous cycles in Norwegian dairy cows and
heifers housed in three herds from March to July 2009. The described stand alone heat detection system records animal
activity at 2 h interval 24-7. Data are transferred by infrared communication when a cow passes close to the antenna.
The recommended interval from the threshold activity alarm signal to artificial insemination (AI) is 15-25 h. The
objective of the study was to investigate cow activity, precision, and optimal time for AI after the alarm signal. Animals
were equipped with activity tags fitted on neck band one or two estrus cycles prior to AI to record normal animal and
herd activity. Threshold activity value was set to 5.0 according to the producer’s recommendations (on a scale from 0 to
approx. 70). The farmer performed visual heat detection minimum twice daily supplementing the data collected from
the control box. Pregnancy was verified by rectal palpation 6 weeks after AI. The average activity level was 20.8 (range
5-62) and the average interval from alarm signal to AI was 22.9 h (range 6.5- 52, SD±8.7). Overall pregnancy rate after
a single AI was 68%, whereas the specific pregnancy rates in each herd were 63, 74, and 73%. There was no difference
in activity level between herds. No differences in average activity level and interval to AI were detected between
pregnant and non-pregnant animals. Parity did not affect activity level or the interval from alarm signal to AI.
Transition from indoor feeding to pasture caused elevated animal activity up to 24 h in all herds. The activity
monitoring system revealed estrus episodes not detected by visual observation. An estrus threshold activity equal to 5.0
was found to be satisfactory for the activity level in Norwegian dairy cows. Based on this investigation, the described
heat detection system is a helpful tool for heat detection in Norwegian dairy herds. The optimal time for AI seems to be
close to 24 h after achieved threshold value for alarm signal.
Comparison of ceftiofur hydrochloride and PGF2alfa for treatment of endometritis in dairy
cows
KHOSHNEVIS S. [email protected]
S. Khoshnevis, M. Moghadam, N. Delvar, N. Nazemi, Tehran, Iran
Endometritis is one of the most general diseases of uterine after parturition in dairy cows. Defining and treatment of
endometritis is very important for improving the reproductive performance. Generally, endometritis is the inflammation
of endometrium and it does not penetrate into the deeper layers.
A cow with endometritis does not have clinical signs but it may affect on involution of uterus that results decrease of
conception rate, increase of culling rate and totally disturbance in the reproductive performance. The aim of this study is
the comparison of ceftiofur hydrochloride and PGF2alfa administration for treatment of endometritis and its effect on
reproductive performance in dairy cows. Ceftiofur is a broad spectrum antibiotic with 0 days withdrawal time in milk
and PGF2alfa is one the most common hormone for treatment of endometritis. In this study, the examined cows were at
30-33 days after parturition and then the cows with endometritis were divided into the two groups. Cows in group 1
(n=33) were treated with PGF2alfa after diagnosis and it was repeated after 11 days. Cows in group 2 (n=26) were
treated daily for 3 days with ceftiofur hydrochloride (Eficur, HIPRA, Spain), (1.1 mg/kg, SC). The period of this study
was about 20 months and there is no significant difference (P>0.05) in days open, conception to service interval,
treatment to first service interval, service per conception, conception rate, first service conception rate and second
service conception rate between two groups. We concluded that administration of PGF2alfa has a more effect on
treatment of mild endometritis but Ceftiofur hydrochloride is more beneficial for severe endometritis.
Evaluation of the antagonistic effects of Lactococcus lactis PTCC 1403 and isolated vaginal
lactic acid bacteria against the most prevalent pathogens of uterine and mammary gland
infections of dairy cows (in vitro study)
MOTTAGHIAN P. [email protected]
P. Mottaghian, P. Dini, Islamic Azad University, Tehran, Iran
M. F. Moghaddam, O.A. Amarloie, F. Mousakhani, Islamic Azad University, Karaj, Iran
The objective of this study was to evaluate and compare the antagonistic effects of Lactococcus lactis PTCC 1403 and
isolated vaginal lactic acid bacteria against the most prevalent pathogens of uterine and mammary gland infections of
dairy cows. Lactococcus lactis PTCC 1403 were obtained from Persian Type Culture Collection (PTCC) reference
laboratory and LAB were isolated from vaginal sampling of healthy cycling Holstein dairy cows during the estrus
phase. Antagonistic effects of L. lactis PTCC 1403 and Isolated LAB were evaluated by agar spot test against indicator
pathogens isolated from specimens of mastitis and various types of uterine infections - including Streptococcus spp.,
Staphylococcus aureus, Escherichia coli, Proteus mirabilis, Klebsiella pneumoniae, Pseudomonas aeroginosa,
Arcanobacterium pyogenes and Clostridium perfringens - which referred to our veterinary laboratory. The measured
inhibition zones were classified as negative, weak positive (+), moderate positive (++) and strong positive (+++). The
two first classes were regarded as resistance. Classes of moderate and strong positivity were regarded as intermediate
and complete susceptibility, respectively. In sum all of the indicator pathogens were susceptible to both L. lactis PTCC
1403 and Isolated LAB. Pseudomonas aeroginosa and Arcanobacterium pyogenes showed the most susceptibility and
Clostridium perfringens showed the least susceptibility to both L. lactis PTCC 1403 and isolated LAB. Furthermore
three strains of Cl. perfringens were totally resistant to the isolated LAB. Regarding the percentages of susceptibility
(89% versus 87%) as well as the mean measured inhibition zones (10.94 mm versus 9.82 mm), there were no significant
(P>0.05) differences between the antagonistic effects of L. lactis PTCC 1403 as a known probiotic and the isolated
LAB.
Reproductive performance in Norwegian dairy herds the last twenty years
REFSDAL A.
[email protected]
A. Refsdal, Hamar, Norway
K. Karlberg, Norwegian School of Veterinary Science, Oslo, Norway
In many countries there has been a decline in reproductive performance in dairy cattle during the last decades. As a
result, the number of inseminations per inseminated cow, days from calving to conception and calving intervals have
increased. At the same time the productivity of dairy cattle has increased considerably, not least because of progress due
to genetic improvement. In contrast to many other countries, Norway has a long tradition of including fertility in the
Total Merit Index (TMI). Viewed against this background, the present study describes the trends in some reproductive
measures in Norway the last two decades.
The results obtained in the present study are based on insemination reports and herd recording files comprising 80.4%
of the herds in 1991 increasing to 98.2% in 2010. Ai-technicians and veterinarians report all inseminations into the AIdatabase, and they are only paid when the inseminations are registered. The data are based on 438150 numbers of first
services in 1991 declining to 300993 services in 2010. The major part of the inseminations is performed with semen
from the Norwegian Red (NRF) breed.
The average number of days from calving to first (CFI) and last insemination (CLI) varied from 81 to 86 days and 104
to 108 days respectively during the period. Both CFI and CLI interval for first lactation cows was consistently 5-6 days
longer than for cows in later lactations. The average non return rate after single inseminations (NR60) increased
significantly from 69.8% in 1991 to 73.4% in 2002 (P<0.001) and then declined to 72.9% in 2010. The overall number
of inseminations per animal inseminated (NIA) was 1.7 during the entire period for controlled animals, and the calving
interval varied between 12.4 and 12.6 months.
In conclusion, Norwegian cattle, mainly comprising the NRF breed, has a high level of reproductive performance and a
positive (NR60) or relatively constant trend (NIA, calving interval) during the last two decades even though the
productivity has increased considerably in the same period. This is in contrast to the declining reproductive performance
reported in many countries.
Studies on common diseases of racing camels in UAE
AL-JUBOORI A. [email protected]
A. Al-Joboori, Abu Dhabi Food Control Authority, UAE
Camels have been formerly considered as hardy animals and less susceptible to most of the diseases that affect other
livestock in the same ecological zones. However, as more research was conducted camels were found to be susceptible
to a large number of pathogenic agents which are major constrains in improvement of camel health. Racing camels are
less susceptible to diseases than other type of camels (milk camel), due to fact that racing camels are kept under healthy
hygienic condition and good nutrition in comparison to other types of camels. The risk factors associated with various
diseases and/or conditions in racing camels are over training/exercise, sudden change of diet, sudden ingestion of large
quantities of carbohydrate rich feed, transport of camels for a long distance by automobile, camel age, season of the
year, overcrowding, poor management, lowered nutritional status and use of illegal medications or supplements. Racing
camels are prone to many diseases, especially ruminal lactic acidosis, lameness, nutritional deficiency, gastrointestinal,
respiratory tract infections, camel pox, contagious ecthyma, camel mange, ringworm, trypanosomiasis and hemorrhagic
disease.
Comparison of diagnostic methods for viral respiratory diseases in sheep naturally infected
AMARAL DA SILVA A. [email protected]
A. Amaral da Silva, J. Simoes Marcondes, M. Alas Martins, R. Calderon Gonçalves, School of Veterinary Medicine
and Animal Science, FMVZ/UNESP, Botucatu, Brazil
Due to the high morbidity and mortality of breathing in sheep, the early diagnosis of these diseases is necessary so that
the veterinary can take appropriate therapeutic and prophylactic measures. Due to the difficulties associated with viral
isolation from clinical samples, the standardization of techniques for the identification of the etiological agents
responsible for an outbreaks of respiratory viral infection in a sheep flocks is a necessity.This work was intended to
characterize the upper and lower respiratory airways cellularity, perform serologic survey antibodies against Bovine
Respiratory Syncytial Virus (BRSV) and Bovine Parainfluenza-3 Virus (BPI-3) and relate these findings with the
histopathologic and immunohistochemical examination of the lungs from sheep with respiratory disease. We used 30
sheep sent to slaughter field: 10 clinically healthy and 20 presenting symptoms of compromised airway detected on
clinical examination. All animals included in the study underwent physical examination, collection of oropharyngeal
and tracheobronchial secretions and lung fragments. We also tested blood samples for antibodies against BPI-3 and
BRSV. The healthy animals were not seropositive for the viruses studied. In the group of diseased animals 36.7%
(11/30) samples were positive for BPI-3 and 33.3% (10/30) for BRSV. The cytological exam revealed significant
difference in the total eosinophils counts in the airways between healthy and sick animals (P>0.012). Among sick
animals, Histopathologic analysis showed 83.3% (25/30) of animals with interstitial pneumonia, 6.7% (2/30) with
fibrinous pneumonia, 6.7% (2/30) with chronic pneumonia and abscess 3.3% (1/30) purulent bronchopneumonia.
Immunohistochemical analysis detected the presence of BRSV and BPI-3 on 20% (6/30) and 13.3% (4/30) of sick
animals, respectively. We can conclude that a combination of direct and indirect diagnostic techniques is useful for
diagnosis respiratory diseases of viral etiology, especially immunohistochemistry, that demonstrated the presence of the
virus BRSV and BPI-3 in sheep with respiratory disease.
Oxidative stress in sheep with pneumonia
AMARAL DA SILVA A. [email protected]
A. Amaral da Silva, M. Alas Martins, R. Calderon Gonçalves, School of Veterinary Medicine and Animal Science,
FMVZ/UNESP, Botucatu, Brazil
A. Dias, Botucatu Medical School, São Paulo State University, Botucatu, Brazil
In domestic animals pneumonia involves an intense inflammatory response in the lungs, causing serious damage to the
structures of the respiratory tract due to oxidative stress resulting from the release of large quantities of reactive oxygen
species (ROS) during the respiratory burst. This study aimed to investigate the oxidant and antioxidant status of healthy
sheep (n=20) and animals with pneumonia (n=20). Blood concentrations of thiobarbituric acid reactive substances
(TBARS) and total glutathione (GSH-t) and antioxidant enzyme activity of superoxide dismutase (SOD) and
glutathione peroxidase (GSH-Px) were determined in the blood of all animals. In parallel, some hematological (total
count of erythrocytes and leukocytes, differential leukocyte count and hemoglobin) and biochemical parameters
(fibrinogen concentrations and total plasma protein) were also determined. Statistical analysis of the blood test revealed
significant increase in the total leukocytes count (P<0.05), segmented neutrophils (P<0.05) and eosinophils (P=0.01) in
the blood of sick animals. With respect to biochemical parameters, sheep suffering from pneumonia showed a
significant increase in the concentration of fibrinogen (P<0.05) and total plasma protein (P=0.04). The marker of
oxidative stress (TBARS) was significantly higher in sheep suffering from pneumonia (P<0.05). Among the
antioxidants, an increase of SOD (P<0.05) and GSH-Px (P<0.05) activity and in the concentration of GSH-t (P<0.05)
were observed in diseased animals. These results demonstrate the occurrence of oxidative stress and lipoperoxidation
during pneumonia in sheep, associated with strong inflammatory response and accumulation of phagocytic cells.
Thrombosis of the cranial vena cava in a 17-year-old Salers cow
BELBIS G. [email protected]
G. Belbis, B. Ravary-Plumioen, G. Avila, Y. Milleman, ENV, Maisons Alfort, France
A 17-year-old Salers cow was referred to the Large Animal Hospital of the National Vet School in Alfort. The referring
vet suspected a pericarditis. At admission, the cow exhibited a severe oedema at the entry of the thorax; along with
swelling of both jugular veins. Normal heart sounds were difficult to hear at the heart auscultation, while no abnormal
sounds were evidenced. The cow kept a good appetite and the body condition score was about 2.5 to 3. Diarrhoea
appeared during the first week of its hospitalisation, along with a marked hyperthermia (up to 40.9°C).
Ancillary complementary exams were undertaken. The Salers cow showed a hypoalbuminemia with a slight
hyperglobulinemia, and exhibited a neutrophilic leucocytosis and lymphopenia. Ultrasonographic examination of the
reticulum evidenced reduced contractions, and fibrinous adherences were suspected. Echocardiography was difficult to
perform and a moderate pericardial and/or pleural effusion was suspected; the heart seemed to have an irregular surface.
Treatment associating broad spectrum antibiotics and NSAIDs was undertaken during the hospitalisation. But, because
of the absence of improvement of the cow’s condition, euthanasia was decided and necropsy was undertaken.
Necropsy revealed fibrinous and fibrous pleuritis, with 2L of a fibrin-rich serous exsudate. Lungs exhibited some dark
red lobules of firm consistency. Tracheobronchic lymp nodes were hyperplasic and congestive. The most interesting
lesion consisted in the presence of a big motley (red and white) thrombus adhering to the cranial vena cava, whose wall
was severely thickened. Along with this most prominent lesion, we evidenced a parareticular abscess, and numerous
abscesses in the liver.
Histomorphological analysis and immunohistochemical detection of Bovine Parainfluenza-3
virus and Bovine Respiratory Syncytial virus in sheep
CALDERON GONCALVES R. [email protected]
R. Calderon Gonçalves, J. S. Marcondes, A. Amaral da Silva, School of Veterinary Medicine and Animal Science,
FMVZ/UNESP, Botucatu, Brazil
The increasing development of sheep breeding has resulted in the largest animals agglomeration of animals indoors,
predisposing them to different challenges causing respiratory diseases, especially viral agents as Type 3 Parainfluenza
and Respiratory Syncytial Virus. Such viruses are incriminated as precursors of respiratory diseases, since they facilitate
the entry of bacterial agents due to damage in lung defense mechanisms. The aim of this study was to describe the
histomorphology of the lung lesions in sheep naturally affected by respiratory disease, and compare the results with
immunohistochemistry for the detection of Bovine Parainfluenza Virus Type 3 (BPI-3) and Bovine Respiratory
Syncytial Virus (BRSV) in lung samples from these animals. We used 30 sheep sent to slaughter field: ten clinically
healthy and 20 presenting symptoms of compromised airway detected on clinical examination. Lung fragments
measuring 2x2 cm were removed from lung lobes with lesions, fixed in buffered 10 formalin, processed histologically
by the usual method and then stained with hematoxylin and eosin (HE). After interpreting microscopic morphology, all
samples that showed abnormal consistent with pneumonia were selected for the immunohistochemistry technique. For
immunohistochemistry, we used anti- polyclonal anti-BRSV serum (VMRD, Inc., Pullman, WA, USA, 210-70 BRSV)
and for detection of BPI-3 we used polyclonal antiserum anti-PI-3 (VMRD, Inc. Pullman, WA, USA, 210-70 PI-3).
Histopathologic analysis showed 83.3% (25/30) of animals with interstitial pneumonia, 6.7% (2/30) with fibrinous
pneumonia, 6.7% (2/30) with chronic pneumonia and abscess 3.3% (1/30) purulent bronchopneumonia. Of the 30
infected patients studied, 33.3% (10/30) showed a positive immunostained for the virus analyzed, 13.3% (4/30) were
positive for BPI-3 and 20% (6/10) were positive for BRSV. We conclude that immunohistochemistry for BRSV and
BPI-3 showed satisfactory results with the protocol used, can be applied in routine clinical laboratories as an as an
important diagnostic tool, contributing in cases where identification of the viral etiological agent is essential for
decision making in the face of outbreaks of respiratory disease.
Arterial blood gas analysis in sheep with pneumonia
CALDERON GONCALVES R. [email protected]
R. Calderon Gonçalves, D.A. Laurenti da Ferreira, A. Amaral da Silva, School of Veterinary Medicine and Animal
Science, FMVZ/UNESP, Botucatu, Brazil
A. Dias, Botucatu Medical School, São Paulo State University, Brazil
Pneumonia is considered serious health problem in sheep production, with significant economic losses due to high
morbidity and mortality. Pneumonia is characterized by an intense inflammatory response in the lungs, which can lead
to serious damage to lung function if not properly contained. The blood gas analysis is a complementary test that can be
particularly used to assess lung function in clinical practice. The aim of this study was to determine arterial blood gases
in healthy sheep (n=20) and clinically diagnosed with pneumonia (n=20). After physical examination, blood samples
were obtained from the carotid artery to perform the gas analysis of all animals studied. Blood samples were taken
using needles connected to plastic syringes containing sodium heparin (about 1000 IU). Blood gas analysis were carried
out immediately after collection in a portable blood gas analyzer (I-STAT®, Abbott Laboratories, Illinois, USA). The
following parameters were determined: arterial oxygen pressure (PO2), partial pressure of carbon dioxide (PCO2),
pressure of hydrogen (pH), oxygen saturation (SO2), bicarbonate (HCO3-), total carbon dioxide (TCO2) and base excess
(BE). The analysis revealed significant increase of PCO2 (P<0.05) and HCO3- (P=0.01) and significant decrease in pH
(P<0.05) in animals suffering from pneumonia. However, only the variable PCO2 was found above the reference values
for the species. There were no significant statistical differences in other variables studied. The results revealed
significant changes in lung function in sheep suffering from pneumonia, reflected mainly by a hypercarpnia due to
alveolar hypoventilation.
In vitro sensitivity of Mannheimia haemolytica, Pasteurella multocida and Histhophilus somni
to three cephalosporins
COLOMER SANS S. [email protected]
S. Colomer, J. Maldonado, L. Valls, HIPRA, Spain
The in vitro activity of ceftiofur, cefquinome and cephalexin against Mannheimia haemolytica, Pasteurella multocida
and H. somni were determined by assesing the Minimum Inhibitory Concentrations (MIC) according to the National
Committee for Clinical Laboratory Standards (NCCLS). All pathogens were susceptible to the drugs tested, although
some differences were observed. For M. haemolytica, cephalexin was the less active drug, while ceftiofur and
cefquinome showed identical MIC values (0.03 µg/ml). Ceftiofur was highly active against P. multocida with a MIC
value of 0.008 µg/ml. The MIC values for cefquinome and cephalexin were 0.03 and 2 mg/ml, respectively. For
H. somni, the lowest MIC value corresponded to ceftiofur, being fourfold more active than cefquinome (0.25 and
1 µg/ml, respectively) and eightfold more active than cephalexin (0.25 and 2 µg/ml, respectively). Taken together, these
findings indicate that ceftiofur is the most active antibiotic against the most relevant respiratory pathogens implicated in
cattle pneumonia, compared to cephalexin and cefquinome.
Diagnostic approach of bovine tuberculosis (bTB) with interferon gamma (IFN gamma) in
Dordogne, France
GHYOROS G. [email protected]
G. Ghyoros, M. Bastos da Silva, Villefranche du Périgord, France
J. L. Moyen, LDA, Coulouneix, France
The objective of this work was to demonstrate the importance of using the interferon gamma test as a new decision
scheme adapted to health management in Dordogne. Until 2000, tuberculosis was considered an "old" disease. Indeed,
until 2003, skin testing detects only a few infected herds. Originally, cases were detected at slaughterhouses. Since
2004, there was a growing awareness of local actors (breeders, health protection group, veterinarians, veterinary
services, and laboratories), leading to better monitoring and an increase in the number of outbreaks found. France is
officially bTB free, as long as prevalence remains below the EU thresholds. Nevertheless, we can not neglect certain
areas that have a disturbing increase in cases since 2006, justifying the introduction of new decision-making patterns
adapted for health management in Dordogne. One of the recent developments is the recognition of IFN gamma as a
diagnostic test. In addition, IGRA (Interferon gamma releasing assay Bovigam® (less than 48 hours), complements the
intradermal test. Recently, campaign in Dordogne (2009/2010) showed a rate of confirmation of infection by 40%
following IFN gamma positive test. This rate is considered excellent, due to the gain of specificity provided by the use
of IFN with specific antigens and a gain of sensitivity of direct controls such as bacteriology and PCR after slaughter.
The animals with an IFN positive test with specific antigens were killed. Non confirmed animal are either non-infected
animals, either infected without lesions whose immune system responded, but over which we have not collected the
samples where the seeds were. In conclusion, the use of IFN gamma is a significant benefit for the evolution of
screening for bTB. IFN after a positive skin test has a very good positive predictive value while maintaining a higher
sensitivity than IDC. Its use in conjunction with IDS allows a gain in sensitivity which is very important, useful for
farms at risk and the implementation of the protocol notwithstanding. The detection of IFN gamma identifies positive
animals sensitized with Mycobacterium bovis, at different times, indicating the efficiency of the method. However, the
disadvantages of the test are the high cost per unit and short time (8 hours) between sample collection and start of the
test.
Selection criteria for antimicrobial treatment of bovine respiratory disease (BRD) based on
target pathogens to be involved
HELLMANN K.
[email protected]
K. Hellmann, G. Braun, J. Rass, I. Radeloff, Klifovet AG, Munich, Germany
Introduction
Veterinarians are requested to use narrow spectrum antimicrobials to treat infectious bacterial disease wherever
possible. Pathogens causing Bovine Respiratory Disease (BRD) are P. multocida, M. haemolytica, Histophilus somni,
Mycoplasma bovis and other Mycoplasma spp. and viruses.
Pathogens may occur concurrently in the same animal on farms. The authors present results of bacteriological
observations, prevalence and relevance of bacterial and Mycoplasma pathogens identified during BRD outbreaks.
Microbiology
All samples were collected either via deep nasal swab (n=1507) or via bronchoalveolear lavage (BAL, n=81). Cattle
sampled showed acute clinical disease. Samples were collected, identified and dispatched via courier to an ISO 17025
or GLP accredited laboratory for pathogen isolation and identification.
Selection of farms
From 1999 to 2010, three to 123 animals of 28 outbreaks of BRD on farms located in Germany and France were tested
based on clinical history of BRD caused by BRD pathogen.
Results
Microbiology
PM was the most frequently isolated bacterial pathogen (89%), identified on 26 farms. MH (71%), HS (46%), MB
(46%) and MO (75%) were also isolated with different frequency.
Mono-infection caused by BRD pathogens
In most outbreaks, more than one pathogen was isolated (92.9%). In only 2 of 28 outbreaks, a single bacterial pathogen
was isolated. In 75% of BRD outbreaks, three or more pathogens were identified.
Correlation of number of samples taken and pathogens isolated
Three to 123 samples were tested per outbreak. On farms, where >15 animals were sampled, at least 3 different
pathogens were identified.
Discussion and conclusion
The results show that BRD is most frequently caused by multiple pathogens. BRD outbreaks caused by just one
causative pathogen are seldom. If sufficient samples are taken, it is likely that 3 or more different causative pathogens
are identified. Mycoplasma spp., PM and MH are most frequently involved. Selecting antimicrobials for treatment of
BRD must take into consideration that the active ingredient and formulation is efficacious in Mycoplasma spp., PM and
MH at the target site of infection for a sufficiently long time period.
Comparison of the injectability of 4 different Florfenicol formulations
MANTECA C. [email protected]
C. Manteca, S. Lacoste, C. Riboud, D. Remmy, Ceva SA, Libourne, France
Objective
The aim of this study is to compare easiness of injection of 4 commercial Florfenicol solutions.
Four commercial solutions of Florfenicol have been used in this trial: Shotaflor (300 mg/ml), Nuflor (300 mg/ml),
Nuflor 450 (450 mg/ml) and Florkem (300 mg/ml).
Fifteen ml of the tested product is suck in a glass syringe of 20 ml set up with a 1.2 mm diameter steel needle. A mass
of 1 kg (equivalent t to 1 Newton) is applied on the piston and the time needed to empty the last 10 ml of solution is
recorded.
This methods is repeated 6 times for each solution at 4°C and at 20°C. Results provided here are the average +/standard deviation and statistical analysis, based on a Student’s t-test.
Results
At 4°C, the times needed to empty the syringe were: Shotaflor: 116+/- 13s, Nuflor 450: 42 +/- 2s, Nuflor 300: 89 +/- 8s,
Florkem: 38 +/- 5s. All these differences are significant (P>0.05) except between Nuflor 450 and Florkem (NS). At
20°C, the times needed to empty the syringe were: Shotaflor: 73 +/- 2s, Nuflor 450: 27 +/- 1s, Nuflor 300: 56 +/- 3s,
Florkem: 23 +/- 0.5s. All these differences are significant (P>0.005).
Conclusions
In case of respiratory diseases, many animals can require treatment, therefore numerous injections can be performed.
This is why comfort and convenience of use due to a good injectability is important in the field. The differences in
performance between the products can be explained by different excipients in their formula. Glycol diethylene allows a
decreased viscosity and thus provides a better injectability than Glycol propylene present in historical products.
Florkem shows the best injectability, including in case of low temperature. This high fluidity strongly increases the
comfort and convenience of use in the field.
Comparison of the syringeabilty of 7 different hydrochloride ceftiofur formulations
MANTECA C. [email protected]
C. Manteca, S. Lacoste, S. Trotebas, Ceva Santé Animale, Libourne, France
Introduction
Different factors have an influence on adherence to prescription by farmer. Easy route of administration, short duration
of treatment, minimum number of injection per day etc… Injection route requires comfort and safety properties of
medicine and ease of injection is one of the most important. High fluidity allows fast injection which mitigates the risk
of inappropriate injection site, local injury or needle breakage.
Seven commercial suspensions of hydrochloride ceftiofur (50 mg/ml) have been used in this trial: Ceftiomax, Ceftiocyl,
Readycef, Truleva, Eficur, Excenel-RTU and Cevaxel-RTU.
Fifteen ml of the tested product is suck in a glass syringe of 20 ml set up with a 1.2 mm diameter steel needle. A mass
of 1 kg (equivalent to 10 Newton force) is applied on the piston and the time needed to empty the last 10 ml of product
is recorded.
This test is repeated 6 times for each suspension after storage at 4°C and at 20°C. Results provided here are the time
average +/- standard deviation and statistical analysis.
Results
At 4°C, the time needed to empty the syringe were: Ceftiomax: 53.0 +/- 2.5s, Ceftiocyl: 55.7 +/- 2.9s, Readycef: 56.2
+/-2.1s, Truleva: 54.2 +/- 0.98s, Eficur: 26.0 +/- 0.62s, Excenel-RTU: 63.8 +/- 3.66s, Cevaxel-RTU: 11.0 +/- 0.5s. All
these differences are significant (P>0.05).
At 20°C, the time needed to empty the syringe were: Ceftiomax: 47.8 +/- 1.6s, Ceftiocyl: 44.7 +/- 0.6s, Readycef: 44.7
+/-0.7s, Truleva: 47.3 +/- 0.8s, Eficur: 26.5 +/- 0.6s, Excenel-RTU: 65.7 +/- 5.9s, Cevaxel-RTU: 12.0 +/- 0.4s. All these
differences are significant (P>0.05).
Conclusions
In case of diseases, many animals can require treatment; therefore numerous injections can be performed. Thus comfort
and convenience of use due to a good syringeability are important in the field. The performance differences between the
hydrochloride ceftiofur products can be explained by different excipients in their formulation. Propylene glycol allows a
decreased viscosity and thus provides a better syringeability. Cevaxel-RTU shows one of the best syringeability and
fluidity, including in case of low temperature. This high fluidity strongly increases the comfort and convenience of use
in the field.
Can botulism in cattle be diagnosed by serology?
MAWHINNEY I. [email protected]
I. Mawhinney, J. Payne, VLA, Sutton Bonnington, UK
D. Palmer, Animal Health Laboratories, Perth, Australia
Previous reports suggest that outbreaks of botulism in Australia can be identified by detecting antibody to botulinum
toxins in surviving cohorts from the affected group. The purpose of this study was to see if the same approach would be
applicable in UK outbreaks, which are frequently associated with use of poultry manure. 300 serum samples from
routine submissions to VLA were used as a negative control group. 140 blood samples were taken from mainly healthy
cohorts in 4 outbreaks of botulism and a few animals that died from suspected clinical botulism in a various parts of
England and Wales. Type D toxin was identified in some outbreaks. Antibody to type C and type D Clostridium
botulinum toxins was tested by ELISA at the Animal Health Laboratories in Perth, Western Australia. The proportion of
samples that were seropositive to type C or D toxin were similar in the control and trial animals at <2%. Some of these
were seropositive to both type C and D. The use of serology in affected animals or surviving cohorts is insufficiently
sensitive to diagnose botulism, at least due to type D intoxication, in outbreaks typical in Great Britain.
Evaluation of Bovilis-BVD vaccine efficacy in sheep against new border disease virus isolates
MEYER G. [email protected]
G. Meyer, M. Deplanche, S. Anne, F. Schelcher - Université de Toulouse, INP, ENVT, UMR 1225, IHAP, Toulouse,
France
A.B. Cay, M. Tignon - CODA-CERVA-VAR, Unit of Enzootic and (Re-) Emerging Viral Diseases, Brussels, Belgium
In 2009, a new epizootic of pestivirus occurred in sheep breeding in a central region of France. The prevalence and
incidence of ovine pestiviruses in the Aveyron department were estimated in 2010 to 5.8% and 1.9% in dairy units and
21.7% and 8.5% in meat units respectively. To characterize the pestiviruses of this epizootic, we firstly performed
phylogenetic analyses of viruses isolated from small weak lambs that suffer with "hairy-shaker" syndrome.
Phylogenetic study, performed on the 5)-non-coding (5)-NCR) and the Npro-coding regions, indicated a border disease
virus origin. Border disease viruses were assigned to clusters BDV-3 for one outbreak and BDV-6 for the other one.
The BDV-3 group gathered isolates reported in Germany, Switzerland and France between 1985 and 2006. The BDV6
group clustered isolates collected in France since the ‘90. This data indicated circulation of two different genotypes at
the same time and in the same geographical location.
We further tested the efficacy of a commercialised inactivated BVD vaccine against the new BDV viruses isolated from
sheep or Pyrenean chamois, by neutralisation assays. Three groups of six sheep were not vaccinated (group 1) or
vaccinated two times at 28 days of interval with half (group 2) or the quarter (group 3) vaccine dose recommended for
cattle vaccination. A neutralising antibody response against BVD and BDV was detected in all sheep of the group 2.
Neutralising antibodies against BVD NADL strain were detected between 4 to 6 weeks after vaccination and reached a
mean peak of approximately 9 log2ED50 2 months after vaccination. Neutralisation antibodies against four strains of
BDV of genotypes 1, 4, 5 and 6 were also found and discussed. In the group 3, only four out of five sheep developed
neutralizing antibodies against NADL that reached a peak two months after vaccination with 3 log2ED50 mean titres
lesser than sheep of group 2. Finally, a challenge with the BDV-3 ncp 10-405 strain, isolated in 2010 in Aveyron was
performed six months after vaccination in the three groups of sheeep, by intranasal inoculation of 106 TCID50 of virus
per animal. Hematological and virological examinations are discussed in regards to vaccine protection.
Simultaneous congenital abnormalities in a new-born calf
MILLEMAN Y. [email protected]
Y. Milleman, G. Belbis, B. Ravary-Plumioen, ENV, Maisons Alfort, France
J.F. Lebon, Flers, France
An eight-day-old female Holstein calf was referred for a supernumerary limb (melomelia) at the level of the left
forelimb.
The calf showed a small supernumerary limb in mediocaudal region of the left forearm. This small limb was about 2 cm
in diameter and 25 cm in length. It was constituted by several articulated bone segments which formed two digits, a
metacarpus, and three small bones more proximally. This abnormality did not interfere with the calf locomotion.
Moreover, a heart murmur was detected at heart examination; the murmur was more pronounced on the right than the
left side. A unique ventricular septal defect or a ventricular septal defect associated with other cardiac congenital
defects was suspected in addition to the limb abnormality.
Ancillary diagnostic tests included an ultrasonographic examination of the heart and a radiographic examination of the
left forelimb. The ultrasonographic examination of the heart showed a ventricular septal defect of about 1 cm in
diameter. The radiographic examination of the forelimb showed that the rudimentary limb was not joined to the ulna.
A surgical resection of the rudimentary limb was undertaken under light sedation completed by a regional anaesthesia
(brachial plexus block) of the limb.
As the growth potential of the calf was compromised due to the heat abnormality, the calf was euthanatized for
necropsy two weeks after surgery. The post-mortem examination revealed a ventricular septal defect of 1.5 cm in
diameter located just below the aortic and sigmoid valves, a moderate right ventricular hypertrophy and a moderate
dilatation of the pulmonary artery base.
This present case shows that an obvious malformation without vital impact (melomelia) can hide another more severe
congenital defect with vital impact (heart disease). If a congenital malformation is diagnosed in a new-born calf, it is
therefore important to search for other congenital defects.
Detection of anti bovine leukemia virus anti bodies in patients with leukemia
MOHAGHEGHZADEH A. [email protected]
A. Mohagheghzadeh, J. Alvani, A. Mohagheghzadeh, A. Yousofi, Islamic Azad University-Zahedshahr branch, Iran
Cancer is the second most common cause of mortality after cardiovascular disease in some countries that in addition to
the problems that creates for the future, heavy economic costs on society to impose. Bovine leukemia virus is a cancer
causing virus of cattle which can be passed from mother cow to calf via the milk BLV commonly inflects dairy and beef
cattle and is found in the marketed milk and meat of these animal. Although there are numerous causes for cancer virus
are of major importance in this field, for example HTLVI and HTLV2 in addition BLV is cancer causing virus of cattle
that is related to above mentioned viruses in the genus of delta viridae and family retroviridae.BLV has many
outstanding features. The possibility of transmission of the virus from cattle to man is real one. Most infected cattle do
not removed from the herd consumption of un pasteurized dairy products or undercooked beef could possibly allow
transmission of infectious virus to humans. BLV infections are not limited for cattle. The virus can infect sheep and
nonhuman primates experimentally and cause cancer in sheep in the laboratory it can infect the cells of many species
including humans and other primates.
A new attenuated IBR live vaccine containing a double genetic deletion gE-/tk- is efficacious
in front of experimental BoHV1 infections, even in the presence of maternally derived
antibodies
MORENO A.
[email protected]
A. Moreno, C. Casado, M. Roca, O. Creixans, Laboratorios Hipra S.A., Amer, Spain
Objectives
To test the efficacy of a new double deleted (gE-/tk-) attenuated live IBR vaccine (Hiprabovis IBR Marker Live,
HIPRA), vaccinating with 2 minimum doses (10exp6.3 CCID50/calf) 21 days apart and infecting experimentally the
animals with a virulent BoHV-1 strain.
Vaccination scheme
Trial 1 (basic vaccination scheme): 5 seronegative vaccinated calves + 5 seronegative mock-vaccinated control calves.
Trial 2 (duration of immunity): 4 seronegative vaccinated calves + 4 seronegative mock-vaccinated control calves.
Trial 3 (influence of maternally derived antibodies): 5 seronegative vaccinated calves + 5 seropositive vaccinated calves
+ 5 seropositive mock-vaccinated control calves.
Challenge scheme (administration of 10exp7 CCID50/calf, intranasal, BoHV-1 Iowa strain)
Trial 1: 21 days after vaccination.
Trial 2: 6 months after vaccination
Trial 3: at the moment when the seropositive control group seronegativized
Follow-up after infection for all trials: monitorization for 21 days for
• clinical signs (general and respiratory),
• rectal temperatures,
• viral nasal shedding.
Results
Trial 1: A great and significant reduction in respiratory and general clinical signs, increase of body temperature, and
viral excretion after experimental infection was observed.
Trial 2: There was still a clear and significant reduction in respiratory and general clinical signs, increase of body
temperature, and viral excretion after experimental infection 6 months after vaccination.
Trial 3: There were almost no differences between the two vaccinated groups as for the significant reduction in
respiratory and general clinical signs, increase of body temperature, and viral excretion after experimental infection,
despite the presence or not of maternally derived antibodies at the time of vaccination.
Conclusions
The efficacy of a new double deleted (gE-/tk-) attenuated live IBR vaccine (Hiprabovis IBR Marker Live, HIPRA) was
demonstrated up to 6 months after the vaccination scheme was completed. The vaccine was also efficacious in the
presence of maternally derived antibodies.
Safety of a new attenuated IBR live vaccine containing a double genetic deletion gE-/tk-.
Dissemination and shedding after vaccination; latency, reactivation and re-excretion after
vaccination and treatment with dexamethasone; abortigenicity and passage through the
placenta
MORENO A.
[email protected]
A. Moreno, E. Desmiquels, C. Casado, M. Roca, Laboratorios Hipra S.A., Amer, Spain
Objectives
To test the safety of a new double deleted (gE-/tk-) live attenuated IBR vaccine, (Hiprabovis IBR Marker Live,
HIPRA):
• dissemination and shedding after vaccination,
• latency, reactivation and re-excretion after vaccination and dexamethasone treatment,
• abortigenicity and passage through the placenta.
Trial 1. 6 seronegative calves: high vaccine overdose (>10exp8.3 CCID50/calf). Necropsies at 2, 4 and 6 days post
vaccination, including swabs, respiratory and reproductive tissues and trigeminal ganglia.
Trial 2. 4 seronegative calves: 2 maximum vaccine doses (10exp7.3 CCID50/calf) 21 days apart. 4 positive control
calves: 10exp7 CCID50/calf of a challenge strain. Three months after vaccination all calves were treated with
dexamethasone and latency, reactivation and re-excretion of the vaccine virus were analysed.
Trial 3. 24 seronegative pregnant cows: a vaccine overdose (10exp8.3 CCID50/cow). All cows were observed daily
until the end of pregnancy.
Results
Trial 1: No viral shedding was detected. No dissemination of the vaccine virus to the different tissues and organs of the
vaccinated animals was detected. No genetic material of BoHV-1 was detected in the trigeminal ganglia.
Trial 2: The vaccine virus was not shed after the dexamethasone treatment. Again, no genetic material of BoHV-1 was
detected in the trigeminal ganglia. In contrast, the positive control calves did shed high amounts of challenge virus after
the dexamethasone treatment.
Trial 3: 22/24 cows remain well until the end of pregnancy. A normal proportion (2/24) of cows aborted. There were no
evidences of IBR infection in these abortions: no virus was detected in placenta or foetus. In contrast, a bacterial
infection was determined in one of the abortions. All calves born to term were in good health and were completely
seronegative to IBR antibodies before sucking the colostrum.
Conclusions
The safety of a new double deleted (gE-/tk-) attenuated live IBR vaccine (Hiprabovis IBR Marker Live, HIPRA) was
demonstrated:
• there was no dissemination or shedding after vaccination,
• no latency (trigeminal ganglia) or reactivation could be detected,
• after dexamethasone treatment there was no viral re-excretion,
• the vaccine virus is not abortigenic: it did not cross the placenta.
Active immunisation and efficacy of a Q fever phase I vaccine (Coxevac®) in adult infected
goats under field conditions
ORSZAGH G. [email protected]
Orszagh G., Ceva SA, Budapest, Hungaria
Manteca C., Ceva Santé Animale, Belgium
Introduction
Shedding of Coxiella burnetii in vaginal discharge or abortion materials are some of the most important sources of
contamination in animals and humans. By immunising animals against Coxiella burnetii, a Q fever phase I vaccine
(Coxevac®) has proved to decrease shedding in dairy goats in experimental trials. However, few data is available on the
efficacy of this vaccine to reduce shedding in dairy goats under field conditions.
The aims of this study were, to describe the humoral immunity provided by this vaccine and its capacity to decrease
shedding in a dairy goat flock under field conditions.
A Q fever outbreak occurred in a dairy goat flock leading to abortions and human Q fever cases. Eighty six, nonpregnant goats, over 3 months of age were annually vaccinated with Coxevac® during 2 years. The non-vaccinated
control group, composed of three seronegative goats, served as sentinel to evaluate the capacity of vaccination to
decrease Q fever spread to uninfected animals.
The animals were observed during 2 years for clinical signs of Q fever. Humoral immunity was evaluated 6 and 18
months after the completion of the first vaccination using an ELISA test (Checkit Q-fever ELISA, IDEXX). Coxiella
burnetii shedding was investigated by real-time PCR on vaginal mucus samples, abortion and placenta material
collected following each kidding and/or abortion.
Results
All animals in the vaccinated and sentinel group remained healthy. No further human cases occurred. All animals from
the sentinel group remained seronegative. In the vaccinated group 34%, 87% and 99% of the animals were sero-positive
respectively 6 months before and after vaccination and 6 months after the annual booster.
Following vaccination, the number of shedders in the vaccinated group decreased from 35% of all samples at the first
kidding season following vaccination to 3% of all samples in the next kidding season.
Discussion
A significant humoral immunisation was reached in all animals after use the vaccination with Coxevac®. Vaccination of
all animals present in the flock reduced the frequency and the shedding level of C. burnetii thereby preventing the
contamination of animals and subsequent zoonotic human Q fever cases.
Surveillance for diseases of the nervous system in cattle in England and Wales over a 10 year
period 2001-2010
OTTER A. [email protected]
A. Otter, Animal Health and Veterinary Laboratories Agency, Shrewsbury, UK
Surveillance for farm animal disease in England and Wales is undertaken at the Animal Health and Veterinary
Laboratories Agency. The details from diagnostic submissions are recorded in databases known as "VIDA" and
"Farmfile". Specific diagnoses include lead poisoning, louping ill, listeriosis, cerebrocortical necrosis,
encephalitis/meningitis, and recently added, botulism. Other recognised diseases are recorded within a category known
as "diagnoses not listed" (DNL), with descriptive text. The laboratory submissions where a diagnosis is not reached
despite reasonable quality of samples and diagnostic testing are recorded as "diagnosis not reached". Scrutiny of these
databases is carried out on a quarterly, annual or ad hoc basis for novel conditions and emergent trends in endemic
disease.
Lead poisoning is the most commonly diagnosed cause of nervous disease each year. It occurs more commonly in
weaned animals and especially in the Spring after animals have been turned out; the most common source of
intoxication is discarded batteries although geochemical sources account for around 20% of cases.
Botulism was rarely diagnosed prior to 2003 but has since shown a marked increased incidence with nearly all cases
associated with direct or indirect contact with broiler manure.
Louping ill and listerial encephalitis are both sporadically diagnosed, and most commonly in adult animals. Louping ill
is strongly geographically related and is only seen in animals at pasture, whereas listeriosis has a wider age range and is
more frequent in housed cattle than those at pasture. Cerebrocortical necrosis, which is usually associated with thiamine
deficiency, occurs mostly in weaned housed animals, with a similar incidence in heifers on dairy farms and in fattening
animals. The diagnosis of encephalitis and/or meningitis is most frequently made in housed unweaned suckler calves.
The "unlisted" diagnoses are relatively common and include BVDV associated cerebellar dysgenesis and
hypomyelination, pituitary abscessation, trauma-induced pathology, clostridial epsilon intoxication, breed-related
conditions such as neuraxial oedema of Polled Herefords, and developmental abnormalities. Previously unreported
conditions have been identified including necrotising encephalitis associated with BoHV-1, disseminated tuberculosis
and encephalitis secondary to Mycoplasma bovis middle ear infection.
Tumoral enlargement of the neck in a three-month-old calf
RAVARY-PLUMIOEN B. [email protected]
B. Ravary-Plumioen, G. Belbis, Y. Milleman, ENV, Maisons Alfort, France
W. Addey, Buchy, France
A three-month-old calf was referred for a mass in the ventral neck region. A percutaneous aspiration by needle had been
previously realised by the referring veterinarian but had failed to collect any liquid. Before admission, the calf had been
treated without any success with antibiotics.
The calf exhibited a marked enlargement of the ventral neck region, along with signs of respiratory difficulty, a
moderate bloat and a moderate growth retardation. The deformation of the ventral neck region extended from the
pharyngeal area to the entrance of the chest and was firm in consistency but not painful. Examination of the respiratory
system revealed orthopnea, dyspnea, roaring and a light bilateral mucopurulent nasal discharge. Examination of the
mouth didn’t reveal any abnormality.
The differential diagnosis included a voluminous abscess or hematoma, a tumoral deformation of some cervical organs
(like thymus or lymph nodes), an actinobacillosis involving lymph nodes or a megaoesophagus. Ancillary diagnostic
tests included another attempt of percutaneous aspiration and an ultrasonographic examination of the ventral neck. Only
a little blood was obtained by percutaneous aspiration. The ultrasonographic examination showed a heterogeneous
hypoechogenic mass with some echogenic focal lesions but without any fluid zone within the mass and no trace of
capsule around the swelling. An abscess or hematoma was therefore unlikely and excluded from the diagnostic
hypotheses.
The calf was finally euthanatized for necropsy. The post-mortem examination revealed a voluminous and firm mass
localised dorsally and on the right side of the trachea and an enlargement of lymph nodes adjacent to the mass. The
surface of mass was nodular and the parenchyma of the mass appeared to be composed of multiples lobules of
homogeneous white-greasy tissue demarcated by white fibrous septa. Lymph nodes were of heterogeneous appearance.
A post-mortem diagnosis of thymic tumor was made at first, then confirmed by histologic analysis. The thymus and
lymph nodes showed a diffuse infiltration of pleomorphic and atypical lymphocytes, confirming the diagnosis of thymic
lymphoma (sporadic bovine leukosis).
Thymic lymphoma generally occurs in cattle aged between six months and two years but sometimes as early as three
months, as in this case.
A Comparison of therapeutic effects of saline solution and dextrose-saline solution on
electrolyte imbalances and electrocardiographic findings in neonatal calf diarrhea
SAYYARI A.
[email protected]
A. Sayyari, M. J. Panahandeh, M. Malekan , Islamic Azad University, Karaj, Iran
P. Mottaghian, H.A. Sterabadi, Tehran University, Iran
Diarrhea in neonatal calves due to the high mortality, treatment costs and poor growth has perpetually imposed serious
economic loss to dairy cattle industry. There has constantly been an ambiguity in application of various solutions and
identifying a more appropriate method in order to correct dehydration and electrolyte imbalances caused by diarrhea
which are effective in causing cardiac arrhythmias and deterioration of patient situation. Thus, the aim of this study is to
evaluate and compare the therapeutic effects of dextrose-saline solution and normal saline solution on electrolyte
imbalances and ECG findings obtained from diarrheic calves. Twenty calves, up to 14 days old, suffering from diarrhea
with 10% and above dehydration were randomly distributed into two treatment groups. The first group was treated
using normal saline solution (0.9%) and the second group was treated with dextrose–saline solution (sodium chloride
0.9% and dextrose 5%). Before treatment, using the base-apex lead, the ECGs of the patients were obtained. Jugular
blood samples were obtained to determine the PCV and consequently to estimate precisely the dehydration percentage
and amount of blood glucose and serum electrolytes (sodium, potassium, magnesium and calcium). Afterwards, the
patients of each group were treated and the blood samples for evaluating the mentioned values as well as ECGs were
obtained. Considering the results of statistical analysis in the first group, there was no significant difference in the
recorded values of variables before and after treatment (P>0.05). In the second group, there was a significant difference
in the values of potassium, calcium, magnesium and glucose variables before and after treatment (P<0.05).
Furthermore, there was no significant difference in the value of Sodium and heart rates before and after treatment
(P>0.05). Among the studied calves, seven showed some cardiac arrhythmias which were all removed entirely after
fluid therapy regardless of the kind of applied solution. Eventually, according to the results of the study, dextrose-saline
solution can be considered as an appropriate choice in order for correction of the electrolyte imbalances caused by
diarrhea in suffering calves.
Efficacy and safety of a new 450 mg/ml florfenicol formulation administered intramuscularly
in the treatment of bacterial bovine respiratory disease
THIRY J.
[email protected]
J. Thiry, V. de Haas, MSD Animal Health, Beaucouzé, France
F. Adriaens, Merck Animal Health, Summit, USA
Bovine respiratory disease (BRD) is of considerable economic significance as a result of morbidity, mortality and poor
growth rates in both beef and dairy cattle. The development of clinical disease and pulmonary lesions has been
associated with infectious bacterial agents including Mannheimia haemolytica, Pasteurella multocida, Histophilus
somni and Mycoplasma bovis. Thus the early use of efficacious antimicrobials is very important to stop the progression
of the infection at the individual level and the spread of the disease in the herd. An injectable 450 mg/ml florfenicol
formulation (Nuflor Minidose; MSD Animal Health) was recently introduced in the market for subcutaneous
administration. The objective of the study was the safety and efficacy evaluation of this 450 mg/ml florfenicol
formulation in the treatment of naturally occurring respiratory disease when administered intramuscularly, compared to
a positive control group treated with the well established 300 mg/ml formulation. A total of 174 calves, selected from 5
sites in France and Spain, aged from 1 to 17 months, showing severe signs of respiratory disease, were randomly
assigned to treatment with either the 300 mg/ml (3 ml/45k g; Nuflor; MSD Animal Health) or 450 mg/ml (2 ml/45 kg;
Nuflor Minidose; MSD Animal Health) florfenicol formulation, both administered intramuscularly twice, 2 days apart.
Animals were clinically observed daily for 14 days following treatment initiation. The predominant pathogens present
in pre-treatment respiratory tract samples were Mannheimia haemolytica and Pasteurella multocida. Mycoplasma bovis
and Histophilus somni were also present. All isolates were subject to in vitro sensitivity testing and found susceptible to
florfenicol. In both treatment groups, rectal temperature dropped and clinical index (depression and respiratory signs)
significantly improved (P<0.05) after treatment. As a result, 97.7% of the 450 mg/ml florfenicol formulation treated
animals were considered treatment successes on day 5. On day 14, 67.82% of the animals were classified as treatment
successes and among them 63.22% were cured. It can be concluded that the treatment by intramuscular injection of the
new 450 mg/ml florfenicol formulation is equally efficacious as the original 300 mg/ml formulation in the treatment of
a naturally occurring outbreak of bovine respiratory disease.
Efficacy of three dry cow intramammary products on cure and prevention of intramammary
infections during dry period and on the control of clinical mastitis post calving
BOUSQUET E. [email protected]
E. Bousquet, Virbac, France
O. Volling, A. Bormann, V. Krömker, University of Hanover, Germany
J. Friedrich, Virbac, Germany
The objective of this study was to compare clinical and bacteriological efficacy of 3 dry cow intramammary products in
modern German dairy herds.
One hundred nineteen dairy cows from 10 herds in Lower Saxony and East Westphalia were randomly allocated to 3
groups at the time of drying off, receiving either Cobactan DC (cefquinome : 150 mg, Virbac), Benestermycin
(penethamate hydroiodine : 100 mg, benethamine penicillin : 280 mg, framycetin sulphate : 100 mg, Boehringer
Ingelheim) or Orbenin Extra (cloxacillin benzathine : 1000 mg, Pfizer). Quarter milk samples were taken weekly on all
cows for bacteriological analysis and somatic cell counts (3 samples before drying off and 3 samples post calving).
Intramammary infection by a pathogen was confirmed if the considered pathogen was isolated at least twice (either
before drying off or post calving). Clinical mastitis cases were recorded till 100 days after calving (milk samples taken
for bacteriological analysis from the concerned quarters). Bacteriological cure of an infected quarter by a given
pathogen at drying off was defined as the absence of this pathogen post calving. A new infection of a quarter was
defined as isolation of a pathogen which was not present at drying off. Statistical comparisons were made by the chisquare test (qualitative criteria) or by analysis of variance (quantitative criteria).
Results
Main pathogens isolated at drying off and post calving were coagulase negative Staphylococci and Streptococcus
uberis. Bacteriological cure rate was identical for the 3 groups (83%). New infections rates ranged between 9.3% and
13.6% in the 3 groups (non significant differences). Quarter somatic cell counts significantly decreased from pre drying
off (geometric mean around 190 000 cells/ml) to post calving (geometric mean below 50 000 cells/ml) but were not
significantly different between groups. Rates of quarters showing clinical mastitis during the first 100 days in milk were
respectively equal to 4.5%, 6.9% and 9.2% in Cobactan DC, Orbenin Extra and Benestermycin groups (significant
difference between Cobactan DC and Benestermycin). Main bacteria isolated from clinical mastitis cases were
environmental pathogens (coliforms, Streptococcus uberis, Enterococci). Differences may be due to different activity
spectrums of products.
Field experience with a vaccine against bovine mastitis in North-East Spain
FRANQUESA O. [email protected]
O. Franquesa, D. Herrera, Q-Llet SLP, Seva, Spain
The objective of the study was to evaluate the efficacy of a vaccine against bovine mastitis (Startvac, Laboratorios
HIPRA) in a commercial dairy herd.
The trial was conducted in a dairy herd with high incidence of environmental mastitis, due to coliform bacteria, CNS
and Streptococci species, located in the north east of Spain. The trial started at March 2010, when the farm was milking
270 cows and the mean milk production was 32L/day/cow. Dry cows, close up cows and fresh cows were housed in
chopped straw bedded pack pens. Lactating cows were housed in freestalls with chopped straw as a bedding material.
All lactating cows, dry cows and heifers to months before calving were vaccinated intramuscularly with 2cc of Startvac
(Laboratorios HIPRA), containing inactivated Escherichia coli J5 and Staphylococcus aureus SP140 strain expressing
Slime Associated Antigenic Complex (SAAC). The farm used blanket vaccination, with a second dosis 3 weeks after.
Every four months blanket vaccination was repeated and only heifers were revaccinated after 3 weeks.
Individual somatic cells count from monthly milk test and clinical mastitis cases were evaluated and compared with the
previous year. During 2010, the farm increased 25% the number of milking cows without any expansion in its facilities
so cow densities increased, making even bigger the challenge to the vaccine.
The parameters compared between 2009 and 2010 were:
• percentage of healthy animals (less than 200.000 cells/ml)
• percentage of new infection risk
• percentage of new clinical mastitis cases
Results
Monthly percentage of healthy cows was higher than previous year (almost 10%) with higher diferences during
summertime (with more E. coli exposure) ; percentage of new infection risk was more than 5% less than previous year
and percentage of new clinical mastitis cases moved from a yearly 125% in 2009 to a 46% in 2010
Conclusions
The vaccine has been efficacious protecting the udder health in the farm, increasing the percentage of healthy cows,
reducing the risk of new infections as well as the percentage of new clinical mastitis cases.
Efficacy of the vaccine Startvac in an austrian dairy herd
HOFER J.
[email protected]
J. Hofer, K. H. Gigler, Herd health services for farm animals of Carinthia, Austria
D. Mansfeld, Institute for Food Safety and Veterinary of Carinthia, Austria
The importance of subclinical mastitis of Staphylococcus aureus is very high. The presence of subclinical mastitis of
Staphylococcus aureus in carinthia is near 30% of the bacteriological findings. The cow associated transfer and the
clinical characteristics make the reduction of the subclinical infections with this bacterium very important for herd
health and the efficiency of milk production. In a dairy farm 18 lactating dairy cows (Simmental FV) with an average
milk yield of 6800 litres per cow S. aureus were detected. Bacteriological status starting the project was positive in 58
udder quarters of 72 totally. All udder quarters were examined by palpation and by California mastitis Test (CMT). The
bacteriological investigations were monitored in 2-month intervals over the period of one year. The vaccine Startvac
was used at 3 times according to the manufacturer's suggested schedule. All heifers were also included in the vaccine
program. The cell account and cell number of individual animals was recorded and evaluated. No corrections were
made at the general milking procedure. Only a hygiene - program with intermediate cleaning and desinfection of the
teat cup liner was carried out and the animals were dipped over a short period of 3 months. 4 animals subjected to
antibiotic treatment.
In the bacteriological study population after the first part of vaccination could already be found a reduction of the
positive findings of Staphylococcus aureus. After 1 year starting the vaccine program individual cell account was
decreased significantly. The bacteriological detection rate of S. aureus after one year decreased from 58 positive
bacteriological findings to only one. The average cell count values of the operation significantly decreased. The
reduction of Staphylococcus aureus herd problems is possible by combining several measures. The use of the vaccine
Startvac seems to be an effective measure to reduce Staphylococcus aureus detection rate on individual dairys and herd
cell account decrease significantly.
Effect of organic zinc supplementation on somatic cell count in cow milk
ILLEK J.
[email protected]
J. Illek, University of Veterinary and Pharmaceutical Sciences, Brno, Czech Republic
S. Dresler, Mendel University, Brno, Czech Republic
V. Kudrna, Institute of Animal Sciences, Prague, Czech Republic
The aim of the study was to investigate the effect of organic zinc source supplementation on somatic cell counts in milk
of cows in peak lactation.
Methodology
The study included 80 Holstein cows, with milk yield from 8,126 to 11,235 kg per 305 day lactation. The study was
carried out in a herd with a long history of zinc deficiency. Zinc concentration in total mixed ration was 32 to 38 mg
Zn/kg on dry matter basis.
Lactating cows were divided into two even groups: Supplemented and Control. All the cows received the same diet.
The supplemented group received 30 mg organic zinc source (Bioplex Zn) kg feed on dry matter basis daily. Mean
dietary dry matter consumption was 21,5 kg in both the groups.
From all the cows, milk samples were collected on a monthly basis, and SCC determined by Fossomatic. In 10 control
cows and 10 supplemented cows, serum zinc concentrations were measured at the start of the trial, and at three month
intervals,using the AAS method. All the cows were monitored for the health status and mastitis occurence for the whole
trial period.
Results
The initial mean somatic cell counts in the Supplemented and Control were 318,230 +- 81,756 and 306,380 +- 85,723,
respectively. In the supplemented cows, SCC in milk was gradually decreasing to 185,220 +- 51,214 at the end of the
trial, whereas the control showed only a slight decrease in SCC (294,652 +- 76,523). A decrease in SCC of the
supplemented group was significant.
The 10 supplemented cows under study showed an increase in serum zinc concentrations. The initial serum zinc
concentrations in the supplemented and control were 10.08 +- 3.12 umol/l and 9.24 +-2.83 umol/l, respectively. After 3
months, serum zinc concentration in supplemented cows was increased to 14.87 +- 1.97 umol/l, and in control cows it
was 10.73 +- 2.7 umol/l.
Conclusion
The results imply that the elimination of zinc deficiency by organic zinc supplementation has a favourable effect both
on somatic cell counts in milk and serum zinc concentrations in dairy cows.
The study was carried out within the project NAZV n. GH81309.
Efficacy of vaccination on mastitis: a tool for control
JIMENEZ GALAN L. M. [email protected]
L. Jimenez Galan, N. Roger, R. Timon, E. Aparicio, Servet Talavera SL, Spain
Mastitis is a disease of much cost on dairy farms around the world; many microorganisms caused intramammary
infections like coagulase negative staphylococcals, Escherichia coli and Staphylococcus aureus in others. The fight
against mastitis has been in the past and is yet in several countries against major contagious pathogens, in the last years
environment microorganisms caused many losses on farms. We need some tools to prevent mastitis besides dry-off
treatment, milking machine performance, milking hygiene, etc.
In this study we try to show the profits of vaccination with Startvac on farms without visible signs of mastitis and
without somatic cell count problems.
From July to December 2010 were selected 228 animals (cows and heifers) were vaccinated with Startvac divided in
vaccinated group was called Treatment Group and non vaccinated group called Control Group. Vaccinated animals
received tree doses, one dose in day 0, second dose in day 35 and three dose day 97. All animals are observed one time
per month to check intramammary infections and check milk production. All intramammary infections were sampled to
determine which microorganisms are caused. All clinical mastitis were recorded and sampled.
In this study we try to show the profits of vaccination with Startvac on farms without visible signs of mastitis and
without somatic cell count problems. Profits are due less intramammary infections and more milk production in
vaccinated animals. Study shows different isolated microorganisms in both groups.
Vaccination with Startvac is a good tool to prevent intramammary infections.
A clinical report of high mastitis prevalence caused by S. aureus in a dairy cows farm
NAVARRO SANSANO C.
[email protected]
C. Navarro Sansano, ESVET Eduard Palma, Barcelona, Spain
Objective
The purpose of this study was try to decrease the SCC, the clinical mastitis rate and the high prevalence of a contagious
mastitis by S. aureus in a farm of dairy cows located in the northwest of Spain, and the goal was to do it without the
elimination of a great number of animals.
The study was made during 2010 (from January to December), the farm has 53 lactation cows with 29 l of milk
production (average), the SCC was 560.000 and the rate of clinical mastitis was 12%. The microbiologic cultures
demonstrated the presence of the following pathogens:
• contagious: S. aureus 41%, Prothoteca 4%, A. pyogenes 4%, S. uberis 2%
• environmental: SNC 4%, S. dysgalactiae 34%
The efficacy of the milk quality program was evaluated every month through the following indicators: SCC in bulk
milk, clinical mastitis rate, health cows rate (means two consecutives controls under 200.000 SCC) and chronic cows
rate (two consecutives controls higher than 200.000)
Milk quality program
1.- Startvac vaccination program: vaccination in blanket (lactation, drying and 7 month pregnant heifers), 3 dosages
(2 ml each) with a 15 days interval. Revaccination each 4 months.
2.- Management: identify and separate contagious animals in order to milk them at the end of the milking. Those
animals couldn’t stay with the health ones till were obtained 4 consecutives negative cultures.
3.- Change in milking parlour and milking machine:
4.- Gradually eliminate chronic animals. The animals positives to A. pyogenes, Prototheca and S. aureus.
5.- Change in antibiotic therapy
Conclusions
In one year the health animals has increased from 44% to 73%. The clinical mastitis has decreased from 12% to 2%,
and the chronic animals have decreased from 32% to 10%.
At the end of the study could observe a decrease in S. aureus prevalence (from 41% to 6%), non presence of contagious
pathogens like A. pyogenes, S. uberis and Prototheca, and the absence of enviromental pathogens like S. dysgalactiae.
In conclusion, in front of highs prevalence of S. aureus, Startvac vaccination, in conjunction with corrective
management, could be a good tool in order to reduce the CSS bulk milk and to improve the health of the farm without a
great animal elimination.
Evaluation of the Startvac® vaccine for preventing mastitis on a farm in the north of Spain
ORTEGA ARIAL DE VELASCO R. [email protected]
R. Ortega Aria de Velasco, Centro Tecnico Veterinario de la Espina, Gijon, Spain
Objective
The objective of this study is to assess the efficacy of Startvac® on a farm with 50 milking cows and production of
25.5 L. and a cell count of 618,000. The indices that have been assessed are: changes in the prevalence of pathogens,
SCC in bulk tank, the rate of cows above 400,000 SCC and rate of cows below 200,000 SCC.
The trial was conducted on a dairy farm where the most important prevalence was S. aureus, CNS and coliforms. The
trial began in June-July 2010 and ended in February 2011.
The vaccine, Startvac®, from Laboratorios Hipra, S.A. was used. A 2-ml dose was administered intramuscularly.
Startvac® contains Escherichia coli J5 and Staphylococcus aureus strain SP140 expressing the Slime Associated
Antigenic Complex (SAAC). The protocol used consisted of blanket administration to all animals: lactating cows, dry
cows and heifers (two months before calving); the dosage was repeated three weeks later and then repeated every three
months.
Conclusions
The vaccine was efficacious in cases of clinical mastitis (reduced from 24% a month to less than 5%). We also detected
an increase in the number of cows, the SCCs of which were lower than 200,000 SCC (which rose from 44% to 60%)
and a decrease in the number of cows with an SCC over 400,000 SCC (from 34% to 22%).
The prevalence of infection with S. aureus was significantly reduced (from 11% to 2%) and the presence of coliform
infection significantly reduced (33% to 7.8%)
In short, the use of the Startvac® vaccine can be a helpful tool both for reducing the incidence of cases of clinical
mastitis as well as for reducing somatic cell counts on dairy farms.
Field experience with a vaccine against mastitis in a farm with colimastitis
SESTO F.
[email protected]
F. Sesto, J. L. Miguez, C. Noya, M. Penelas, M. Lopez, Seragro, Spain
Introduction
The purpose of this work is to describe the apparition of a colimastitis case in a farm and demonstrate how a vaccine
against mastitis could belongs to a quality milk protocol and improve in this way the farm rates.
Description
The farm is located in the northwest of Spain, with 240 cows in straw bedded pens and a parallel milking parlor with 12
x 2 points.
Every month were checked the following critic points: milking routine, milking machine, feeding and cow comfort.
Mastitis incidence:
The farm is assessed in control and prevention of mastitis from 2002 till end of 2009 with the following rates:
• SCC in milk tank lower to 200.000,
• absence of mastitis with acute and hiperacute symptoms,
• rate of clinical mastitis lower than 3%.
From end of 2009 to September 2010, the situation changes dramatically because appears a very high mastitis incidence
characterizated by an hiperacute symptoms caused by E. coli, the affected cows were in various productive phases, SCC
were higher than 200.000 and the rate of cows with SCC higher than 1.000.000 were 5%.
In the evaluations of the critic points made every month, never was found an alteration that persists along the time and
who could was the cause of the coliform mastitis incidence.
That was the reason because decided to vaccine in blanket with Startvac® (Hipra laboratories), in June 2010.
The evolution after the vaccination was the following:
• a decrease in the average of SCC in tank from 223 to 157,
• an increase of health animals (<200 SCC) from 78% to 85%,
• dramatically reduction in coliform mastitis incidence.
Conclusion
Startvac ® vaccination, as a part of a quality milk program, helps to improve the rates and productivity of the farm.
The usage of the vaccination, in conjunction with a milk quality program, decreases the mastitis severity and the SCC
and increase the number of health cows in a farm.
Use of the vaccine Startvac in a dairy farm with problems with S. aureus
WERNITZNIG J. [email protected]
J. Wernitznig, Vienna, Austria
In a dairy farm with 19 Simmental-cows with a high prevalence of S. aureus the vaccine Startvac with an effect against
S. aureus, E. coli und CNS was used.
Introduction
The therapy against subclinical mastitis is the use of antibiotics. Thereby mastitis can sometimes be cured. Against
S. aureus this therapy is mostly not effective. With vaccination against mastitis there is now a prophylactic alternative
to the use of antibiotics available. New studies show that by vaccination against S. aureus, E. coli and CNS better
results in the control of these infections can be reached.
For the evaluation of the prevalence of S. aureus quarter milk samples were taken and analysed bacteriologically three
times in an interval of one week. Further milk samples were taken every fifty days two times in an interval of one week.
All cows and heifers were checked 15 times in the year 2010. With 370.000 cells/ml in the bulk milk the delivery block
was threatened.
The whole herd was vaccinated with Startvac and 4 weeks later a booster was injected. Then the vaccination scheme of
the manufacturer was accomplished. The heifers were vaccinated in the standard vaccination scheme (45 and 10 days
before and 52 days after calving).
Results
From the 19 cows S. aureus was found in 7 animals. 50 days after the booster only in 4 cows S. aureus was still
detectable. One cow stayed S. aureus positive on one quarter during the whole research period. At the first check up the
SCC was lower than 100.000/ml at 42% of the animals and at 9,2% higher than 800.000/ml. One week after the first
vaccination the SCC reduced to 200.000/ml. The threatened delivery block was resolved.
Five months after the vaccination at 10,5% of the animals the SCC was inbetween 200-400.000 cells/ml but already
84,2% had a SCC under 100.000/ml. Since the start of vaccination no new infections with S. aureus could be detected.
Discussion
The vaccination of the whole stock reduces the infection impact remarkable. Also the SCC is influenced positivly.
All heifers that where incorporated in the herd were kept from an infection with S. aureus. It is very important to
include them into the vaccination program. A new introduction into the herd can be prevented.
Conclusion
The preventative vaccination with Startvac is a very promising alternative to the antibiotic therapy of mastitis.
The innate response of mammary epithelial cells to different S. aureus isolates
ZECCONI A.
[email protected]
A. Zecconi, R. Piccinini, M. Mazzili, DIPAV, Milan, Italy
S. aureus is still the most important contagious mastitis pathogen worldwide. Previous papers showed that S. aureus
isolates have different virulence patterns and S. aureus strains are very often herd-specific. The aim of this study was to
assess the relationship between S. aureus strains characterized by different virulence patterns and the innate response of
a mammary epithelial cell line (BME-UV). Ten S. aureus isolates from subclinical mastitis cases in dairy cows from
different herds were considered. Isolates were selected from our strain collection based on their genetic characteristics
and antimicrobial susceptibility. BME-UV was exposed to S. aureus cultures for 24 h. Extracellular and intracellular S.
aureus counts were performed by standard agar plate dilution method, intracellular and extracellular lysozyme and
NAGase were measured by fluorimetric assays. The results at 4 h after challenge showed higher intracellular counts
than extracellular ones, suggesting that S. aureus internalization is an early event and it is not depending from the
extracellular concentration. During the experimental period, lysozyme concentration was associated to the increase in
bacterial counts, what suggests that a minimum concentration of about 102 cfu/ml is needed to elicit a cellular response.
Finally, lysozyme and NAGase activities showed to be associated to S. aureus genetic patterns in accordance to
previous observation suggesting that the different immune response to S. aureus intramammary infections is influenced
both by cow and by S. aureus characteristics.
Effect of a organic form of selenium on selected haematological and biochemical parameters
in calves
BEDNAREK D. [email protected]
D. Bednarek, K. Dudek, M. Szyma*ska-Czerwi*ska, NVRI, Pulawy, Poland
The aim of the study was to evaluate the effect of organic form of selenium (Sel-Plex, Alltech) on the selected
haematological and biochemical indices in calves. The study was curried out in twenty 10-12 weeks aged calves
randomly divided into two equal groups. The animals in the first group (n=10) were treated with 0.68 g the organic
selenium preparation (Sel-Plex) i.e. each animal received per day 0.3 ppm Se+. The preparation was administered once
a day by 11 weeks and calf blood for laboratory investigations was collected once a week. The following indices were
determined: RBC, HCT, MCV, HGB, MCH, MCHC, WBC, LYM, MID, PMNL, PTL, MPV in whole blood of calves,
and also total protein, glucose and selenium concentration in their serum. The obtained result indicated the stimulating
effect of organic selenium on the haematopoetic system in treated calves manifested with the increased values of mostly
haematological parameters in compared with the controls. In the animals the significantly higher concentrations of
selenium in serum were also reported. Moreover, the contents of total protein and glucose in serum of the animals were
increased too pointing to the significance of selenium, especially its organic forms in the metabolic processes in
mammal organisms.
Subclinical ketosis cases in Algeria
DECHNOUCHE K.
[email protected]
K. Deghnouche, Mohamed Kheider University, Algeria
M. Tlidjane T. Meziane, Hadj Lakhder University, Algeria
The chronic shortage of animal feed in Algeria (weak forage) suggests a high prevalence of metabolic diseases.
Therefore a preliminary study was conducted in 2010 to determine the prevalence of subclinical ketosis in some dairy
farms. Sixty cows Pius black, multiparous, clinically healthy, divided, into two lots, D: dry cows (n= 30), and E: early
lactating cows (n= 30), were selected in three different farms (A, B, C). Farms A and B Traditional type, are located in
an arid area (Biskra) and Livestock C semi-intensive situated in a temperate region (Constantine). A net energy deficit
was found for the three farms, it has been estimated at 1.67, 2.13 and 0.84 kg of milk respectively for farm A, B and C.
The concentrations of serum parameters studied (cholesterol and triglycerides), and the activity of enzymes (AST and
ALT), were close to physiological values except for glucose which was 0.45 g/l in dry cows and 0.36 g/l in early
lactating ones. The Labstix test in milk and urine was found positive in thirty six out of sixty cows. The distribution of
subclinical ketosis by rearing revealed a high prevalence in farms A and B. It was found that subclinical ketosis is a
metabolic disorder very common in the studied farms. It is not only higher in cows in early lactation as reported by
different bibliographical sources, but it is also found in the dry period in our research.
Changes in subcutaneous fat tissue in periparturient dairy cows
FLEISCHER P. [email protected]
P. Fleischer, O. Penkava, S. Slosarkova, J. Doubek, University of Veterinary and Pharmaceutical Sciences, Brno, Czech
Republic
The objective of this study was to evaluate the changes in the mean area of adipocytes and macrophages (MP)
infiltration of the subcutaneous fat tissue in periparturient dairy cows in relation to the body condition score (BCS, 1 to
5 scale) and biochemical markers of lipomobilisation.
A total of 30 Holstein cows or heifers were included in the study. From each animal, a pair of samples of blood and
subcutaneous fat was collected. The first sampling was performed 2 to 20 days (mean 8.6) ante partum (a.p.), and the
second one 1 to 12 days (mean 7.4) post partum (p.p.). The fat samples were obtained from the regio clunis using
bioptic forceps. The mean area of one adipocyte was calculated from 20 cells bearing a nucleus. The macrophages in
the sections of fat tissue were stained using the indirect imunohistochemistry with primary antibody anti-CD68 (clone
EBM 11) and the staining system CSA-HRP (both DAKO, Denmark). The number of MP was counted as a number of
stained cells in five fields of vision under a magnification of 10x40. Blood sera were examined for the levels of nonesterified fatty acids (NEFA) and beta-hydroxybutyrate (BHB). Statistical analysis included the Wilcoxon test for group
comparison of paired samples and the Spearman test of correlation.
The mean area of one adipocyte amounted to 7 371 square $m a.p. and 5 831 square $m p.p. with a highly significant
difference (P<0.001). The mean count of MP infiltrated in fat tissue was significantly (P<0.01) higher p.p. (1.57 a.p.,
3.87 p.p.). A significant relationship between adipocyte area and MP counts was observed only p.p. (r=0.54; P<0.05).
The area of adipocytes a.p. was in a negative correlation with the level of BHB a.p. (r=-0.49; P<0.01). The rate of
decrease in fat cell area was in correlation with levels of NEFA and BHB a.p. only; with NEFA in a positive way
(r=0.43; P<0.05) and with BHB in a negative way (r=-0.38; P<0.05). There weren’t any significant relationships
between counts of MP and biochemical parameters as well as between BCS and any other parameter.
The results confirmed the premise of increased macrophage infiltration of fat tissue after the periparturient load in dairy
cows. The confirmed decrease in adipocyte area around the parturition appears to be in relation with serum levels of
NEFA and BHB.
Supported by the grants IGA VFU No. 51/2010/FVL and NAZV No. QI91A238.
The usefulness of acute phase proteins in farm animal medicine
KOVAC G. [email protected]
G. Kovac, C. Tothova, O. Nagy, University of Veterinary Medicine and Pharmacy, Kosice, Slovak Republic
Presented study was aimed at the evaluation of selected acute phase proteins (APPs) in various physiological conditions
(after birth, after parturition), and during some inflammatory disease conditions in cattle. The first part of this study
deals with the evaluation of the concentrations of major bovine APPs, haptoglobin (Hp), serum amyloid A (SAA) and
fibrinogen (Fbg) during the first 6 months of life. The obtained data showed a significant influence of age on the
investigated parameters. The most marked changes we recorded in the concentrations of SAA characterized by higher
values in calves during milk and transitional feeding periods. In the second part of the study, we evaluated the
concentrations of APPs, and some other biochemical variables in dairy cows in the period from 4 weeks before till 10
weeks after parturitiion. Our findings suggest a significant influence of reproduction cycle on the monitored variables,
with the highest concentrations of Hp and SAA in cows in the early postparturient period. Similar trend was observed in
the serum concentrations of non-esterified fatty acids and +-hydroxybutyrate by significant positive correlations with
the evaluated APPs, suggesting strong relationships between the acute phase response and physiological changes around
parturition. In the third part of the study, we analyzed the influence of various inflammatory diseases on the
concentrations of APPs in calves. The obtained results showed increased production of evaluated APPs in calves with
respiratory diseases. Moreover, presented data indicated that other diseases in calves, e.g. diarrhoea and
omphalophlebitis, although in a less extent, may also induce an acute phase response. In the fourth part of the study, we
evaluated the influence of mastitis in dairy cows on the concentrations of mammary associated milk amyloid A (MAA).
The obtained results indicated elevated production of MAA in cows with clinical changes on the mammary gland, and
also in cows with sub-clinical mastitis. The findings presented in the fifth part of the study showed elevated production
of APPs also in heifers affected by hoof diseases and lameness. The obtained results suggest that APPs may be a
meaningful contribution to the laboratory diagnosis and may provide suitable additional diagnostic information.
Metabolic profile and organic feed in dairy cows
UBALDI A. [email protected]
A. Ubaldi, A. Fusari, University of Parma, Italy
R. Matarrese, G. M. Lacalandra, University of Bari, Italy
"Organic breeding" was introduced as an innovative and healthy technique to breed dairy cows and to produce milk
destined to humans. According to animal needs, some of the major ingredient have been changed: indeed, in the case of
this study soya-bean has been replaced with Vicia faba subsp. minor and so on. From the nutritional point of view,
quantitative features of fed have been conserved changing only the qualitative characteristic of row materials, which
had to came from growing rigorously organic.
We studied a herd of dairy cows (95 subjects) comprising multiparous lactating cows and heifers in order to evaluate
the significant clinical and metabolic alterations following to a drastic feed change (traditional-organic).
The blood samples were collected before (1 week) and after (1 week, 1 month, 2 months) feed change to perform the
metabolic profiles.
The sharp transition between feed provoked significant variations in metabolic parameters in cows in different lactating
stages during the first month. Several blood parameters returned to "traditional" values, while others reached stable and
different blood concentrations compared to the beginning of trial.
Most important metabolic variations were registered in dry cows group: increase of albumin, glucose, calcium and
phosphorus; decrease of urea, total lipids, GOT, GGT and total bilirubin. On these basis, we can assert that nutritional
status of the dry cows, such as the hepatic functionality, have been ameliorated.
Similar trend (decrease of GOT and total bilirubin values) was recorded in lactating animals, confirming the
amelioration of the hepatic status.. Hyperlipidemia showed in the first collection recovered and glicemia increased.
In heifers, we recorded increase of glicemia and calcemia and decrease of GOT, total bilirubin and urea. This pictures
confirms better hepatic and nutritional status. The amelioration of clinical status of heifers improved the insemination
index.
As regard to milk production, an improve of the quality parameters, expecially in middle lactation cows was recorded.
In conclusion, we can assert that feeding variations permits (after 70 days) the production of a "high quality organic
milk" in dairy cows and contributes to improve, also, reproductive performances in heifer and metabolic status in all
groups of subjects.
Off-label use of ceftiofur in dairy cows: clinical and metabolic impact
UBALDI A. [email protected]
A. Ubaldi, A. Fusari, E. Parmigiani, G. Morini, University of Parma, Italy
Ceftiofur is semisynthetic 3rd generation cephalosporin. Ceftiofur sodium/HCl is indicated for treatment of bovine
respiratory disease in cattle. Ceftiofur HCl is also approved for foot rot in cattle. No milk withholding time required
when administered as labeled. In this work the Authors report the "off-label" use of ceftiofur in the dismetabolic status
in post partum period in bovine.
For this study, 810 dairy cows were employed. Bovine were fed with one daily TMR (total mixed ration). Subjects were
divided in treated (706 subjects) and control group (104 subjects). Treatment was administred immediately post partum
in a single dose of 20 ml Naxcel® (4.0 g/subject of ceftiofur) at base of the ear.
Afterwards, these examinations were realized: recurrent body temperature and clinical signs 30 days along post partum;
blood samples were collected first, third and seventh days post partum; determination of blood NEFA, Triglycerides
and BHB (beta-OH-butyrrate) in a random group of 100 treated subjects and 46 control subjects utilizing commercial
kit; control of the decrease of ingestion and body weight with evaluation of BCS; daily milk production.
Serum parameters concentrations revealed: decrease of haematic concentration of NEFA and BHB and unchanged
values for Tryglicerides.
These laboratory findings confirm the absence, in the treated bovine, of the clinical and subclinical ketosic status. The
laboratory diagnosis supported the clinical observations.
The antibiotic activity of Ceftiofur acts on the energetic metabolism, too, especially on the lipidic metabolism. Use of
Ceftiofur produces the following variations: decrease of fever episodes, metritis, ketosis, left abomasal displacements
and deaths.
Moreover, connected to the amelioration of the clinical post partum status of the treated cows, at 30th day, we reported
a better value of BCS, confirming the preventive action of the drug on pathological status. This permits to animals to
meet the production and reproductive efforts more easily.
In the treated group, reproductive performances improved like uterine involutions, average time parturition first A.I.,
average numbers of inseminations per pregnancy and average number of pregnancies within the second A.I
In conclusion we can assert that ceftiofur can be of helpful to buiatric practice to prevent metabolic and reproductive
diseases.
Foot lesions in dairy cattle in Switzerland: prevalence and risk factors
BECKER J. [email protected]
J. Becker, M. Reist, A. Steiner, VetSuisse Faculty, Bern, Switzerland
As part of a project designed to approach the problem of lameness and pain in dairy cattle, this study was performed to
assess the prevalence of foot lesions in dairy cattle in Switzerland and to evaluate possible risk factors.
1543 dairy cows of 78 herds were investigated at routine claw trimming from 2010 to 2011 in Switzerland. Locomotion
score, body-condition score, cleanliness of leg, udder and flank and the following foot lesions were assessed: digital
dermatitis, heel-horn erosion, Rusterholz sole ulcer, sole ulcer, white line disease, double sole, hemorrhage, widened
white line, subclinical laminitis, chronic laminitis, interdigital hyperplasia, interdigital phlegmona, infection of the toe,
lesions with deep structures affected.
Structured personal interviews with the associated farmers were arranged to investigate possible cow-level and herdlevel risk factors. Potential risk factors included into the statistical analyses were: breed, cleanliness, body-condition
score, acidosis, ketosis, endometritis, mastitis, other foot lesions, housing system, regular outdoor exercise, factors
concerning farm as type of production, size of herd and farm, income by dairy farming, feeding and forage, claw
trimming and farmers’ opinions as to the importance of claw health. Within-herd prevalence was used as the dependent
variable for herd-level risk factor analysis.
Herd prevalence of lameness was more than 75%. Heel-horn erosion, Rusterholz sole ulcer and digital dermatitis
occurred in more than 70% of herds, white line disease and interdigital hyperplasia in more than 30%.
Prevalence of further foot lesions and cow-level and herd-level risk factors for foot lesions are currently being
evaluated; results will be presented by means of the poster.
Attitudes towards painful interventions at the feet of dairy cattle in Switzerland
BECKER J. [email protected]
J. Becker, M. Reist, A. Steiner, VetSuisse Faculty, Bern, Switzerland
Lameness is not only a problem of economic loss but also of animal welfare. As prevalence of lameness increases,
painful surgical interventions at the feet of cows are performed more often. Administration of local anesthesia is
required in cases involving the pododerma, but it is usually not done because of various reasons.
A project was designed to approach this problem, assessing attitudes towards painful interventions of the feet.
Attitudes of 77 farmers and 32 claw trimmers towards painful interventions of the feet were assessed during personal
interviews, 137 bovine veterinarians responded to an equivalent online survey.
The sensation of pain of cows was judged to be significantly lower than of humans and horses in all three groups of
surveyed persons. Veterinarians considered significantly more often the administration of local anesthesia for surgical
excision of a sole ulcer to represent a useful intervention than claw trimmers and farmers did. Costs for pain
management did not reveal to be the main issue for the farmers’ attitude. The knowledge of the statutory provision of
Switzerland that anesthesia has to be administered in any case of painful intervention, was low among farmers and
veterinarians.
Further parameters are currently being evaluated and compared to findings of studies from other countries, and results
will be presented by means of the poster.
Evaluation of the Narcotrend for monitoring anesthesia in calves
DOLL M.
[email protected]
M. Doll, M. Metzner, C. Sauter-Louis, Klinik für Wiederkäuer, Oberschleißheim, Germany
O. Klaus, Medizinische Hochschule Hannover, Hannover, Germany
T. Kneif, Klinikum Region Hannover, Hannover, Germany
Most surgeries in calves are done under general anesthesia. In humans, additional EEG monitors, such as the
Narcotrend, are increasingly used. The Narcotrend monitor converts the original EEG into a numeric index from 0
(deep anaesthesia) to 100 (awake). The aim of this study was to test the Narcotrend in calves.
In 43 Simmental calves, aged 2 days to 4.5 months, anesthesia was monitored and data collected during surgery and the
subsequent waking or deepening phase. The animals were divided into two groups according to the general condition
and sensorium – either unremarkable (group 1) or disturbed (group 2).
For anesthesia the standard protocol of the Clinic for Ruminants was used, namely xylazine, ketamine and isoflurane.
The patients breathed spontaneously throughout the entire anesthesia. Depth of anesthesia was assessed by clinical
parameters. It was divided into four planes: "awake", "too light", "adequate” and "too deep". At the moment of skin
incision and manipulation of the peritoneum it was noted whether or not movement following the surgical stimulus
occurred. The EEG was visually analyzed, looking for burst suppressions. This, as well as the evaluation of the
deepening phase was done for both groups. All other analyse were done only for animals with undisturbed general
condition and sensorium.
Results
There was no discernable relationship between the Narcotrend index and the clinically determined plane of anesthesia.
Furthermore the Narcotrend index did not reflect the analgesic part of anesthesia. Between the Narcotrend index and
end-tidal isoflurane concentration there was a weak significant correlation (Spearman) (group 1: r=0,309, plane of
deepening (both groups): r=0,317), which was contrary to what we expected. Regarding both groups, the EEG epochs
were correctly classified in 97.7% regarding burst suppression pattern. However, there was a large difference regarding
the incidence of these patterns (group 1: 1.6% ; group 2: 31.3%)
Conclusion
Under the given circumstances, the Narcotrend could make no contribution to the monitoring of anesthesia in calves.
Study of myocardial bridges in cattle
MOHAGHEGHZADEH A. [email protected]
A. Mohagheghzadeh, A. Mohagheghzadeh, Islamic Azad University, Zahedshahr, Iran
S. Vaez Badiehgard, Shiraz, Iran
Myocardial bridges in human and number of different species of animals is described and classified. In formulation of
the classification special attention was given to the location, width, thickness of muscular layer of the bridge and the
number of commitant veins of the over bridge artery. Myocardial bridge is an anatomic arrangement which lies across
the coronary arteries. In this survey 120 cattles who come to slaughter-house in kazeroon have been studied after
slaughter if they had myocardial bridge. 49 cases had myocardial bridge that 83.3% were paracoronal and 16.6% were
subsinosal. Myocardial bridges associated with other risk factors are an important cause of Myocardial infarction in
human beings. In animals these structures were reported in necropsy.
Bovine radiology - Digital diagnostic atlas
STEINER A.
[email protected]
A. Steiner, U. Geissbühler, M. Stoffel, A. Siegrist, VetSuisse Faculty, Bern, Switzerland
Literature on bovine radiographic evaluation is rare and limited - with the exception of one book dating from 1989 - on
publications about selected anatomic regions and clinical cases. Bovine radiographic knowledge however is desired in
regions and breeds, where individual bovine medical care is practiced. Furthermore, the comprehension of comparative
radiographic findings in different species and the acquisition of bovine radiographic anatomy are of significant value for
student’s and resident’s education.
Normal and abnormal bovine digital radiographs of the appendicular skeleton, the head, the vertebral column, the
pelvis, the thorax and the reticulum were chosen and collected from our electronic image archive. Abnormal
radiographs originate all from clinical cases. As often as possible, normal radiographs from calves and adult cows were
also collected from clinical cases (for example comparative radiographs of the contralateral limb of a cow with
lameness). All the missing normal radiographs were performed either on a fresh dead born calf or on an adult cow
determined for slaughter. The images of this cow were performed under the supervision and with permission of the
national animal protection committee.
Image quality optimizing, correct image orientation and image labelling were performed with the aid of graphic
software. Radiographic anatomic structures were labelled and named under the supervision of an anatomist (MHS) and
a board certified radiologist (UG).Then the images were uploaded as jpeg-files on an in house programmed, Microsoft
Windows® based image viewing software.
Normal images were completed with schemes to illustrate image acquisition technique and with information about
exposure and positioning data and used auxiliary radiographic equipment.
The radiographs of the clinical cases were completed with labels pointing at the radiographic findings, with a clinical
case report and with a radiographic report.
The electronic atlas was completed by text chapters about software instructions (handbook), applied radiation
protection, radiographic interpretation guideline and systemic skeletal diseases.
A demo version of the atlas is accessible at
http://www.dkv.unibe.ch/content/wiederkaeuerklinik/education_training/radiology_atlas/index_eng.html.
The atlas can now be ordered at: [email protected]

Palais du Pharo, Marseille 16-18 Nov. 2011

Transcription

Similar documents

Dairy Daily Grind at Toreja Dairy Farm in Bgy. Dayapan, Ibaan

Livestock Opportunity - Indian Agricultural Program of Ontario

The Jackson Family Farm spans five generations, over 100 years

In 1928, Amelia Earhardt took her first successful flight over the

FMC Dairy Corporate Brochure - Professional Dairy Producers of

SNU Rally at the Fallon Cantaloupe Festival September 2012

7000 Head Herd Dispersal