Influence of assistance during hatching on the mortality and growth

Influence of assistance during hatching on the mortality and growth

Arch . Geflügelk. 2000, 64 (1). 40-41, ISSN 0003-9098 . © Verlag Eugen Ulmer GmbH & Co., Stuttgart
Influence of assistance during hatching
on the mortality and growth rate of ostrich chicks
Effekt einer Hilfestellung beim Sch lupf von Straußenküken auf d ie spä tere Mortal ität
und W ach stumsrate
J. O. Horbaficzuk 1 and J. Sales 2
Manuskript eingegangen am 30. November 1998
Introduction
A major problem in the ostrich industry is the poor survival of chicks from hatching till 90 days of age and the
lack of knowledge about why the birds died (DEEMING
et al., 1993). DEEMTNG and AYRES (1994) found that
25.0 and 90.2% of chicks assisted and unassisted during
hatching, respectively, survived under quarantine conditions (up till 35 days after the last bird has hatched).
However, these figures were based on sampIe sizes of 8
and 51, respectively. Although it is common practice in
the ostrich industry to assist chicks during hatching
(HALLAM, 1992), DEEMING and A YRES (1994) stated that
this resulted in poor quality birds being maintained and
that the problems associated with chicks not hatching
are not being investigated. The aim of the present study
was to determine the influence of the assistance during
hatching on the mortality and growth rate of ostrich
chicks up to 60 days of age.
Material and methods
Two hundred and forty ostrich eggs, from 14 females, a1l
in their third year of laying and kept in trios, were incubated in multi-stage PasReform incubators at standard
conditions. Eggs were sanitised in paraformaldehyde after
collection, stored for a maximum of 9 days at 12-15 °C
and sanitised again before setting. On day 39 viable eggs
were transferred ioto the hatcher.
Chicks were reared in indoor pens on a plastic mesh
15 cm above the floor, at a density of 0.8 m2/chick during
1-30 days of age had 1.2 m2 /chick during 30-60 days.
From 4 weeks of age chicks had access to outdoor pens
(5 m x 9 m). Room temperature was maintained initially at
32.5 °C for newly hatched chicks and reduced daily by
2 °C until ambient temperature remained between 2324 oe. Feeding and zoohygienic considerations of all
chicks were uniform. PeUeti sed food concentrate specially
formulated for ostrich chicks was supplied to the chicks
ad libitum from hatching to two months of age. Fresh
water was continuously available. From the second week
after hatching small amounts of finely chopped luceme
was provided periodically during the day. The pens were
I Polish Academy of Sciences, Institute of Genetics and Animal
Breeding, Jastrzebiec, Mrok6w, Poland
2 Department of Animal Sciences, University of Stellenbosch,
Stellenbosch, South Africa
cleaned at least once a day. Chicks were weighted on day
1,3, 7, 10, 14,2 1,30, 40,50 and 60.
Chi square (X 2 ) tests were used to evaluated differences
in percentage of chicks died between providing assistance
and without providing assistance and time period of death.
Growth rate (y) over time (x) was describe by a quadratic
equation of the form y = a + bx + cx 2 . Unpaired t-tests
were used to evaluate differences in a, band c between
chicks assisted and not assisted (SNEDECOR and COCHRAN,
1991).
Results and Discussion
Although there was no difference (X2 = 0.937) in the percentage of chicks died between the two groups at any time
interval (Table 1), the tendency was found that mortality
rate was higher at 15-60 days for chicks that have received assistance during hatching, especially after 31 days
of age. This implicated that factors other than assistance
du ring hatching depressed the influence of assistance on
mortality during an early stage. The majority of chicks
died within the first 14 days after hatching had unabsorbed yolk sacs.
The quadratic regression parameters for assisted and
non-assisted chicks is shown in Table 2.
Toble 1. Percentoge of chicks (% of total in group) d ied ot certoin
intervals
Anteil verendeter Küken nach dem Schlupf in verschiedenen Altersabschnitten (in % der Küken in der Gruppe)
Doys
Without ossistonce
(n = 63)
Assistonce
(n = 36)
0- 7
8- 14
15 - 30
31 - 60
4.8
9.5
7.9
6 .3
5.6
8 .3
11.1
13 .9
Toble 2. Growth constonts (y =
60 doys of oge
0
+ bx + cx 2 )
of chicks up to
Regressionsgleichungen für den Wachstumsverlauf der Küken
bis zum 60. Lebenstag
Without
assistance
Assistance
n
o
b
c
63
0.844 ± 0.098
0.011 ± 0.017
0.001 ± O.OOO
36
0.872 ± 0.116
0 .016 ± 0.021
0 .001 ± O.OOO
Archiv für Geflügelkunde 1/2000
HORBANCZUK and SAlES, Assistance during hatching of ostrich chicks
No differences (P> 0.05) were found in any of the
parameters between groups. The form of this equation
cIearly illustrated the initial decIine in weight of ostrich
chicks after hatching previously reported (DEEMlNG et al.,
1993; DEEMING and AYREs, 1994).
It should be emphasised that in present investigation the
majority of chicks (40-45%) that being assisted were malpositioned (HORBANCZUK et al., 1997), mainly "head in
small end" (malposition II, where the embryo was inverted
withjn the egg with the head in the end away from the air
space (LANDAUER, 1967». In this position external pipping
is rarely possible, which means that about 15-18 hours
after internal pipping the embryo must be assisted. Apart
from thi , egg shell thickness exceeded 2 nun in the present study, in comparison to an average of 1.83 nun reported for ostrich egg shells (SALES et al., 1996).
Especially, factors responsible for mortalities up to
14 days of age needs further investigation. However, assistance during hatching has no intluence on the growth
rate of ostrich chicks up to 60 days of age.
Summary
The influence of assistance during incubation on the SUfvivability and growth rate of ostrich chicks up till 60 days
of age was investigated in the presented study. Although
assistance during incubation has no influence (P > 0.05)
on neither mortality rate nor growth rate up tiB 60 days of
age, there was a tendency of higher mortality rate from
day 15 to 60 for chicks assisted.
Keywords
41
Obwohl sich die Hilfestellung beim Schlupf nicht auf die Mortalität oder die Wachstumsrate bis zum 60. LT ausgewirkt hat
(P > 0.05), zeigte sich eine Tendenz zu einer etwas größeren
Sterblichkeit zwischen dem 15. und 60. Lebenstag für die Küken ,
denen beim Schlupf Hilfe gegeben wurde.
Stichworte
Strauß, Brut, Schlupf, Überlebensrate
References
DEEMI 'G, D. C. and L. AYRES , 1994: Factors affecting the growth
rate of ostrich (Struthio camelus) chicks in captiv ity. Vet. Rec.
135, 617-622.
DEEMING, D. c., L. AYRES and F. J. AYRES, 1993: Observations
on the comrnercial production of ostrich (Struthio camelus) in
the United Kingdom: Rearing of chicks. Vet. Rec. 132, 627-
631.
HA LLAM , M . G., 1992: The Topaz lntroduction to Practical Ostrich Farming. The Ostrich Producers Association of Zimbabwe, Harare, Zimbabwe.
LANDAUER, W., 1967: The hatchability of chicken eggs as influenced by environment and heredity. Monograph 1 (revised),
Stors, The University of Connecticut, USA.
HORBANCZUK, J., T. CELEDA and S . ARMATOWSKJ , 1997: Selected
abnormalities in late dead embryos and hatchings in ostriches.
The Ostrich News (USA) 107, 45-51.
SALES, J., D . G. POGGENPOEL and S. C. CILLIERS, 1996: Comparative physical and nutritive characteristics of ostrich eggs.
World 's Poultr. Sci. J. 52, 45-52.
SNEDECOR, G. W . and W. G. COCHRAN, 1991: Statistical Methods,
8th ed., Iowa State University Press, Ames, USA.
ostrich, incubation, hateh, survivability
Zusammenfassung
Effekt einer Hilfestellung beim Schlupf von Straußen küken
auf die spätere Mortalität und Wachstumsrate
In der vorliegenden Untersuchung wurde der Einfluß einer Hilfestellung beim Schlupf auf die spätere Überlebensrate und das
Wachstum von Straußenküken bis zum 60. Lebenstag untersucht.
Archiv IVr Geflügelkunde 1/2000
Korres pondenzad resse: J. O. Horbaiiezuk, Ph.D., Polish Aeademy of Seienees, Inst. of
Genelies and Animal Breeding, Jastrzebiee, 05·55 1 Mrok6w, Poland.
e- mail : o lav@rackelma il .col11