GOAT THERIOGENOLOGY

GOAT THERIOGENOLOGY
Theera Rukkwamsuk
Dept. of Large Animal and Wildlife Clinical Science
Faculty of Veterinary Medicine
Kasetsart University
Alpine (French) : Dairy goat
Toggenburg : Dairy goat
Saanan : Dairy goat
Angora : Fiber goat
Boer : meat goat
GOAT
• Short-day breeders, with breeding season.
• From late August or September to late
January or February in Northern
Hemisphere.
• The Nubian dairy goat generally has longer
breeding season than dairy breeding
originating in Europe.
GOAT
• In regions near the equator where day
length varies little during the year, the
breeding seasons are correlated more with
rain and improved nutrition than simply
with season of the year.
• In region far from the equator, breeding
season may be restricted to a few months
(Oct - Dec)
TERMS USED IN GOATKEEPING
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BILLY : ADULT MALE
BUCK : ADULT MALE (DAIRY GOAT)
DOE : ADULT FEMALE
NANNY : ADULT FEMALE
DOELING : YOUNG FEMALE FROM BIRTH
UNTIL FIRST FRESHENING
TERMS USED IN GOATKEEPING
• FIRST FRESHENER : female that has had
one set of offspring
• FRESHENING : parturition
• GOATING : young goat from birth until
puberty
• KID : young goat from birth until puberty
• KIDDING : parturition
• WETHER : castrated male
PUBERTY
• ANY TIME AFTER 4 MONTHS OF AGE
DEPENDING ON
• : SIZE ( approximate 65% of their adult body
weight)
• : SEASON OF THE YEAR ( born early or late
in the kidding season)
PUBERTY
• Undersized doe kids may breed and
conceive only to undergo stress
abortion in mild to late gestation.
• Yong Angora nannies are often not
exposed to males until the second
breeding after they are born.
MANAGEMENT OF BREEDING GOAT
• Detection of estrous : presence of buck
or teaser buck
• The male effect : the sudden
introduction of a male to females that
have not been to exposed to a male at
least 30 days will induce ovulation
within 3 days in female if they are
transitional.
TRANSITION
• Refers to the reproductive state in
which female are not cycling, but
are approaching the breeding
season and so are more easily
induced to cycle than during deep
anestrous.
MANAGEMENT OF BREEDING GOAT
• Flushing : the technique of
supplementing nutrition for several
weeks prior to the breeding season
to increase in ovulation rate.
MANAGEMENT OF BREEDING GOAT
•Male : female ratio
- with natural service, one fertile buck per 50
does.
- Buck are capable of serving as many as 20
time / day.
- Young bucks in their first year of breeding
: 1 : 25 does
- Buck should be good body condition when
turned in with the female (deworm, foot trim)
MANAGEMENT OF BREEDING GOAT
• Timing of routine procedures :
deworm and foot trimming
• Breeding record.
• Breeding to an outside bucks.
PLANNING A BREEDING PROGRAME
USING THE MALE EFFECT
• Would be separate the bucks from the
does at least 1 month prior to breeding
season
• begin flushing the females 2 weeks
prior to introduction of the male.
• Introduce the male suddenly at the
desired onset the breeding season.
USING THE MALE EFFECT
• Infertile teaser animal can be used for
this purpose.
• This should result in most females
ovulating during the 10-day period after
introduces of the male.
• The male effect is reduced as the
breeding season progress.
SHORT ESTROUS CYCLES
• Due to lack of progesterone priming.
• Many of first estrous cycles observed (up
to 75%) during breeding season are short
(4-7 days).
• The first ovulation will not result in
conception because the CL formed is
short-lived.
SHORT ESTROUS CYCLES
• Management technique is to used infertile
teaser with the females for the first week and
then turn in the desired sires.
• One group of bucks can be turned in at the
beginning of season and replaced with a
rested group of bucks after the length of one
estrous cycle.
• AI might also best be postponed until the
second observed estrous.
OUT-OF-SEASON BREEDING
• Healthy animals that are proper size and
condition.
• Does that are less than 60 days postpartum
are not good candidates for successful outof-season breeding.
• Bucks should either be placed under lights
ahead of time, or should have been
continuously used since the previous
breeding season.
OUT-OF-SEASON BREEDING
• Continued use can help maintain libido in
buck during the none breeding season, but
dose not prevent the seasonal decline in
semen quality.
• A lower female : male ratio should be
considered during non breeding season(10:1) .
OUT-OF-SEASON BREEDING
• Light : exposed to 19-20 hour days for
two months at which time the extra
light are tuned off.
• Decrease in day length will stimulate
the goat to start cycling approximately
7-10 week later.
OUT-OF-SEASON BREEDING
• Melatonin : exogenous melatonin signal the
body that darkness is present, thus
indicating that day are suddenly shorter.
• Hormone : progestin and equine chrionic
gonadotrophin.
ESTROUS CYCLE IN GOAT
The Estrous Cycle
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Usually 21 days unless in transition
Standing heat for 24 (to 72+) hours
Estrogen dominant for 2-4 days
Progesterone dominant during luteal phase (1214 days)
• Phases: Estrus (day 0-1), metestrus (day 1-5),
diestrus (day 6-17) and proestrus (day 18-20)
Control of Estrous Cycle
• Doe’s hormones
• Day length (season or
artificial light)
• Presence or absence of
bucks
Breeding Options
• Doelings: 60-70% of mature weight, or by 10-12
months old maximum
• Does: Two-three months after kidding (for three
kid crops in two years)
• Every Fall, as does cycle naturally
• When she stands for buck
• AI: 12-18 hours after start of estrus
Out-of-season breeding techniques
Assess body condition score before breeding
Early re-breeding means early weaning
POSTPARTUM PERIOD
• Goat usually breed during the autumn
and kid 5 month later.
• This is the anestrous season, so the
animals do not resume cyclicity
postpartum until the subsequent
autumn.
POSTPARTUM PERIOD
• Animals that kid during the breeding
season and have a postpartum period
similar to that observed in cattle.
• Normal goat will begin estrous cycles
30-40 days after kidding during
breeding season. Uterine involution is
complete at this time.
DETECTION OF ESTROUS
Does in estrous will : seek the male
: flag their tail vigorously
: vulvar hyperemia
: present of mucus
: increased vocalization
: frequent urination.
DETECTION OF ESTROUS
• Heat detection is not reliable without
the presence of buck.
• Homosexual activity is not as
prevalent in does as it in cows.
• Teaser animals can used.
• Buck rags are the rags that are
saturated with buck odor.
Signs of heat are:
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Unusual restlessness and bleating
Continuous twitching of the tail
Decreased milk production
Decreased appetite
Redness and swollen around the vulva
Mucous discharge that wets the hair around the tail
Attempts to fight molest and annoy other goats
Rubbing against other animals
Mounting other animals or standing to be mounted.
SYNCONIZATION OF ESTROUS
THE MALE EFFECT
HORMONE
: PROSTAGLANDIN
: PMSG
: PROGESTERONE
PROSTAGLANDIN
• Two injection (11 days apart).
• Show sign of estrous 36-60 hour after
injection.
• Functional CL are present from day 4 to
day 16 of the 20-day estrous cycle.
PROGESTERONE+PMSG
• Use in non breeding season.
• P4 can administered by vaginal implants, ear
implants or daily injection for 9-15 day.
• Administered 300-600 iu of PMSG 48 hour prior
P4 removal.
• Standing estrous starting 12-36 hours after
removal P4.
PROPER TIME OF BREED
• Goat ovulate 30-36 hours after the onset of
standing estrous.
• Typically bred 12-24 hour after they are
first observed in standing heat.
• Goat may remain in standing estrous for
24-36 hours.
MATING SUPERVISION
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HAND-MATING
PEN-MATING
PASTURE MATING
ARTIFICIAL INSEMINATION
PREGNANCY
Pregnancy Detection
• Lack of heat
• Lack of interest in/by
buck
• Hormonal assays (milk,
serum)
• Ultrasound
• Doppler
• Hulet’s Rod
• Ballottement
• X-rays
EARLY DEVELOPMENT OF THE CONCEPTUS
• Embryo enter the uterus on the third to
fourth day after estrous.
• 11 day after fertilization, the blatocyst is
about 1 mm diameter.
• Attachment of the chorioallantois to the
endometrium is cotyledonary, beginning
in the caruncular areas at about 17-20
day.
EARLY DEVELOPMENT OF THE CONCEPTUS
• Tranuterine migration of embryo is
common.
• Approximately 10-20% of embryo from
double ovulation on one ovary
migrating to contralateral uterine
horn .
ESTIMATEING THE STAGE OF GESTATION
• 1.78 * ( BIPARIETAL DIAMETER(MM) +1.46)
• CROWN-RUMP MEASUREMENT
• = (fetal length (inched)/ 0.149) + 30
LENGTH OF GESTATION
• Breed average for gestation length vary
from 143 days(Black Bengal) to 153 days
(Murciana breed).
• Most average fall in the range of 146-150
day.
• The genotype of the fetus influences
variation in gestation more than
genotype of dam.
LENGTH OF GESTATION
• There is a tendency for does carrying
female kids, does carrying multiple
kids and does kidding during the
breeding season to have shorter
gestation.
NUTRITION DURING THE LATE GESTATION
• Close attention should be paid to the
nutrition of goats during the last 4-6 weeks
of gestation because of their susceptibility
to pregnancy toxemia.
• Animals in confinement may be gradually
introduce to 0.5-0.7 kg of concentrate per
head per day.
BOOSTING COLOSTRAL IMMUNOGLOBULINS
• Pregnant does should be vaccinated
approximately 1 month prior to
expected parturition.
• These disease include
enterotoxemia(overeating disease cause
by Clostidium perfringens) and tetanus.
TERMINATION OF PREGNANCY
• Because goats are dependent on
corpus luteum as a source of
progesterone throughout gestation,
pregnancy can be terminated at
any time through the
administration of prostaglandin.
PREGNANCY DIAGNOSIS
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NON RETURN TO ESTROUS
PROGESTERONE TEST
ULTRASONOGRAPHY ( 30 DAY)
OESTRONE SULPHATE (50 DAY)
RADIOGRAPHY (75-80)
MISCELLANEOUS METHOD ; BALLOTTMENT
PRENATAL LOSSES
• Environmental factor such as
temperature and nutrition play an
important role in ovulation rate and
very likely in embryo survival rate.
• Fertilization failure and EED are
higher during the early part of
breeding season.
PRENATAL LOSSES
• Heat stress and selenium-vitamin E
deficiency may also be associated
with infertile and EED in small
ruminant.
• Infectious causes of abortion can
cause significant losses in goat.
PARTURITION
SIGNS OF IMPENDING PARTURITION
• Development of mammary gland.
• Relax of the sacral ligament in the
last days of gestations.
Normal Kidding
• Phase 1 = Prepatory period (ligaments relax,
udder fills, fetus repositions, cervix dilates,
cervical plug discharged) ; lasts 12-36 hours
• Phase 2 = Labor and delivery of kid(s); lasts 560 minutes
• Phase 3 = Passage of fetal membranes and
placenta; lasts 0-12 hours
Phase 1
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Pacing
Vocalizing
Off by self
Gets up and down often
Looks at abdomen
Doesn’t eat
Paws ground
May leak milk
Tailhead ligaments very loose
Fetus is being presented to cervix,
causing dilation
• Vulva swollen
Phase 1
Phase 2
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Doe usually lies down
Fetal membranes appear
Abdominal presses evident
Nose and/or feet appear
5 to 60 minutes between kids
Phase 2
Phase 2
Presentation of fetal nose
Phase 2
Delivery of fetal head
Phase 2
Phase 2
Note angle of lamb’s body with respect to ewe’s pelvis
and mimic this when helping to deliver kid/lamb/calf/foal.
Completion of Phase 2:
Delivery of Lamb
Completion of Phase 2:
Delivery of Kid
Beginning of Phase 3: Expulsion of Fetal
Membranes and Placenta
Lochia: Normal for up to three weeks
post-kidding. Dark red, no foul smell.
INDUCTION OF PARTURITION
• Injected with 10-20 mg of
prostaglandin F2α after 140 days of
gestation.
• Goats will usually kid 27-50 hours
(mean 31 hour) after being injected
with prostaglandin or one of its
analogues.
Dystocia = difficulty with delivery
Causes:
• Fetal-maternal relative size mismatch
• Uterine inertia (fatigue, low calcium)
• Maternal factors: ringwomb, hernias,
pelvic fracture...
• Malpresentation of fetus
• Fetal monsters or malformation
Malpresentations
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Head back
Leg(s) back
Jumbled-up twins/triplets
Transverse
True breech (rump and tail presented)
Posterior presentation (hind feet
presented)
• Poll presented
Keys to Assisting:
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Be clean
Be gentle
Be patient
Use lubricant
Small hands help
Twins can be very confusing
Take time to figure out what you feel
Look for key landmarks you can identify
Have assistant retract does’ vulva
Be willing to be “repulsive” (retropulse kid
back into doe)
Questions
• Is she dilated enough?
• Does she just need a tincture of
time?
• Front leg or hind leg?
• One or more kids? Which parts
are which?!
• Should I check for another kid?
When to Assist:
1. Malpresentation
2. No progress after one hour of
active labor (doeling) or one half
hour (doe)
Head Back
• Very common
• Could confuse with breech
presentation
• Won’t feel tail or anus
• Check for ear, eye, teeth.
• Angle of mouth is a good
handle
• Can be difficult to correct if
kid dead a while
• Head snare can help
Leg Back
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Also very common
ID front leg vs. back
ID twins, single or triplets
Follow leg to chest to other
shoulder; follow leg to knee,
bend knee tightly closed, cup
hoof in hand, lift up and
forward while pushing shoulder
back; hoof must be delivered
first
• Must protect uterus from hoof
Reproductive Problems
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Dystocia
Pregnancy toxemia
Milk fever
Abortions
Retained placentas
False pregnancy
Nymphomania (cystic ovaries, Copper def.)
Prolapsed uterus
Retained Placenta
• Retained beyond 12 hours
• Causes: infections, premature, abortion,
selenium deficiency, calcium deficiency
• DON’T PULL!
• Treatment: call your vet
– Oxytocin
– Perhaps Lutalyse®
– Antibiotics (intrauterine vs. systemic)
– NSAIDs help with fever, inflammation,
toxins
– Tetanus booster
Prolapsed Uterus
• Associated with lack of exercise,
nutritional deficiencies and/or dystocia
• Treatment: call your vet
– Clean, clean, clean (use HOT soapy
water)
– Elevate hind quarters
– Use gentle fists, not fingers
– Antibiotics, oxytocin, tetanus booster
– No need to stitch vulva if uterus
replaced properly
– “Bit” or bite block prevents doe from
straining against prolapse reduction
efforts
Causes of Abortions
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Spontaneous regression of CL
Toxins
Exogenous hormones
Fetal malformation/genetic error
Trauma
Maternal illness (fever,
starvation)
• Too many feti for uterus to
support
• Campylobacteriosis
• Selenium deficiency
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Listeriosis
Salmonella
Steroids
Molds/fungi
Toxoplasmosis
Leptospirosis
Immune factors
Chlamydiosis (last
2-8 weeks);
treatment and
vaccination
available
Neonatal Kid Care
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COLOSTRUM! When in doubt: tube feed
Dip navel with 7% iodine; clip to 1-2”
Check doe’s udder; strip out teats
Vitamin E/Selenium injection
Tag, tattoo or other ID
+/- anti-toxins, depending on doe’s vaccination
history
• Keep warm
• May need enema in 1-2 days.
• Beware of Floppy Kid Syndrome...
Record Keeping
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Birth weight
Animal ID
Dam and sire
Number of kids
Kidding ease
Treatments,
medications
Weaning weight
Dates of routine
procedures
Illnesses
Birth date
Number of kids
weaned
Pounds of kids weaned
Kidding Supplies
• See handout
• ESSENTIAL:
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tube feeder
Bo-Se®
Iodine
Thermometer
Epinephrine
Disinfectant soap
Synchronizing Estrus
• Why??
• Methods
1. Progesterone sponges, implants or feed
additive for at least 14 days, +/- FSH; heat in 35 days.
2. Prostaglandin (Lutalyse ®or
Estrumate®) injections for herd; repeat in 10-11
days; most in heat 2 days later. Goat must have
CL for treatment to be effective
• You will need to have enough bucks or straws
to service all does!
NOTE: none of these products are approved for use in goats
Superovulation and Embryo Transfer
• Cost prohibitive for most herds
• Being used by purebred Boer breeders and
breeders of other rare or high-value breeds or
individuals
• Steps: synchronize donor and recipient;
superovulate donor; breed/inseminate donor; flush
embryos; implant embryos in recipients
• Nutritional flushing two weeks pre/post-breeding
associated with increased number of ovulations
Artificial Insemination
• Reasons
• Growing in availability, practicality and
popularity
• Steps: semen collection, processing,
storage, insemination
• Inseminate 12-18 hours after estrus starts
• Methods: cervical, trans-cervical and
laparoscopic
Breeding Out-of-Season
• Reasons
• Remember: most breeds respond to
decreasing day length and start cyclingin
August or later.
• Methods: (combination is best)
Melatonin orally, injection or implant
Artificial Light: 16 hours of light
Male effect (new buck => greater
effect)
Artificial Day Length
• Two months of 16-19-20 hour days, or
1-2 hr. of bright light 16 hours after
dawn; holds off cycling
• After two months, return to short day length;
does start cycling in about 6 weeks
• Add buck for added male effect
• Consider electricity bill...
Hormonal Manipulation of Out-of-Season Breeding
(during anestrous period)
• Progesterone source for 11 days (d. 0-11)
• Give prostaglandin and PMSG on day 9
• Estrus 36-48 hr. later
Influences on Buck Fertility
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Temperature
Season
Health
Nutrition
Genetics
Selecting Bucks
• Positive traits of buck and progeny!
(weaning weights, dressing percent, rate
of gain, conformation, etc.)
• Fertile! (Re-assess each year)
Normal external genitalia
Libido
Normal ejaculate (microscopic exam)
• Healthy and sound
SUMMARY
• The best reproduction program is part of an
entire herd health program
• Nutrition plays a very important role
• Colostrum, colostrum, colostrum!
• Know due dates for best management!!!
• Not every animal should pass its genes on
• Plan breeding to hit best market dates with
kids
• To turn a profit, you must learn how to do most
treatments and interventions yourself