Small Ruminants Flashcards
where does the sperm mature?
in the epididymis
what is unique about the ram penis?
it has the vermiform appendage. the ram can live without it and it doesn’t affect fertility, but the idea is to spray the semen on to the cervix
how long does it take for sperm to mature and be produced
47 days (6-8 weeks)
healthy mature rams and bucks make how much sperm a day
10 billion sperm a day (wowee)
how does season affect ram and buck semen production
during the off season (feb to july) the testes are softer and dont produce as much sperm
how is the cervix of the sheep different than other mammals?
it has sort of salloon doors staggered like a zipper, making it VERY hard to get through the cervix or do cervical AI! During mating the penis does not go through the cervix
how many cervical rings do goats have
3
sheep and goats are seasonally polyestrus. what does this mean?
they will cycle repeatedly until they either get preg or the season ends
in what season do female sheep cycle?
sheep are short day breeders (opposite of horses), so they cycle from about august to january in the northern hemisphere. This depends on the breed of sheep tho, some sheep have very short cycles, some have longer cycles.
true or false: sheep near the equator will cycle all year round
true because they rely on changes in daylight and if there is none, nothing will change!
what happens during the transition period?
cycles are irregular and fertility is decreased
how long is gestation in sheep/goats?
approx 5 months(150 days)
how long is the estrous cycle in sheep and goats?
sheep: 17 days
goats: 21 days more like cows
true or false: ewe lambs and doelings have shorter cycle lengths
true, theyre like heifers and tend to take less days to cycle
how long is estrus in sheep and goats? differences between them?
30 hours (2-3 days)–>stand to be mounted by the male
sheep are quiet when theyre horny unless you have a teazer ram, but goats are much easier to tell, theyre let you know
during diestrus, what are the ovaries doing?
forming new follicles to be ready to ovulate next estrus if there’s no conception
corpus luteum forms at each ovulation site
the CL in sheep and goats is unique. how so?
stress can destroy the CL and cause early embyronic loss. this can be caused by poor nutrition, excessive handling, illness, etc
how is the GOAT CL unique?
goats require a CL for full term of pregnancy and abortion will occur if the CL regresses at ANY point during pregnancy. in sheep the fetus contributes a little more progesterone production but in goats it’s all the CL!
high progesterone in diestrus leads to what behavior?
rejection of the male
high esotrgen during estrus leads to what behavior? be specific
acceptance of the ram–>actively seek them out, tail flagging, standing to be mounted
describe the breeding behavior of the ram when it’s time to breed
what is one thing unique to goats?
sniffing the vulva, flehmen response, test for estrus by kicking the female, extends the head and neck.
goats: urination on beard and front legs which the females like apparently
when preparing males for the breeding season, what kinds of things are you doing? and how soon before breeding season are you doing these things?
6-8 weeks before:
- reduce stress which can damage semen such as frostbite, fever, bad nutrition (takes 47 days to make new sperm)
- look at body condition, you want 3.5 at breeding. fat males have poor libido and bad semen quality (fat deposits in scrotum and messes with thermoregulation)
ram to ewe (or buck to doe) ratio depends on what things?
age of the male: mature rams can handle 30-50 ewes himself, ram lambs can only do 15-20
seasonality and breed: if it’s not prime time for the specific breed, the ram/buck might only breed 5 females
size of breeding area: rams get to fewer females in a pasture setting bc it takes time and effort to find them
single sire vs multiple groups: competition and fighting between rams
synchronized females: if ALL the females are in heat for just one day, can he get to them all? most mature rams/bucks can only do like 10 and ram lambs might get overwhelmed
what things are you doing 6-8 weeks out (from letting rams/bucks out) for the females?
body condition scoring: we want 3-3.5 at breeding
nutritional flushing of ewes/does to increase ovulation rate: feed more calories just before to give them a boost. doesn’t work if the animals are already fat. don’t give protein, just calories (grain/barely)
why do ewe lambs/doelings need to be managed separately from mature females?
they are still growing AND they will be pregnant too
they need better nutrition: more protein and more concentrate
they need adequate bunk space (can get pushed out by mature females and wont get the food they need)
the mature females can be aggressive
what age are ewes and doelings first bred? how much do we want them to weigh?
7-8 months of age
should weigh 70% of mature bw
some people also wait another year to breed them for the first time so theyre around 18 months old, they do this in the UK
why is ideal body condition so important for ewe lambs/doelings
if too thin= they wont conceive or lose pregnancy
if too fat=prone to vaginal prolapse and dystocia, decreased milk production
how long is the breeding season for sheep and goats? what should the conception rate be?
sheep os 35 days, for goats 42 days MAX. this allows for 2 full cycles and a lambing/kidding period of 45 to 50 days.
conception rate should be 95 to 100 %
why should you NOT leave rams/bucks out for a long time?
the females will lamb/kid late and this is annoying and these animals dont breed well, they need to be culled
benefits of a short breeding season?
easier to manage nutrition of pregnant ewes/does (theyre all the same days of gestation)
nutrition and disease prevention is more effective in lams/kids (older animals spread disease to younger animals and this way theyre all the same age)
management is more efficient: ultrasounds, shearing, nutrition changes in late gestation, parasite control, vaccines, breeding testing, selection of replacements
implantation occurs when
day 16
what can you use to abort a sheep/goat?
Estrumate (a PGF) injections before 30 days of pregnancy
the placentome is made up of
maternal side=caruncles
fetal side=cotyledon
briefly describe the 3 stages of parturition
stage 1: contractions start, restlnessnes, 2-12 hrs, she may not come for grain, may not notice at all
stage 2: delivery of lams/kids, 1-2 hours, can take longer if multiple babies
stage 3: delivery of placenta, within 6 hours is normal, longer than 24 hours is retained, nursing of lambs may help get placenta to come out (more oxytocin released). Discharge of lochia for a few weeks (uterus cleaning itself)
when should you vaccinate females before giving birth?
4 week before
describe the 30 minute rule
if theres 30 minutes of pushing and nothing has happned=yikes
after one baby is born and 30 mins has gone by with nothing=yikes
should see the baby up and nursing within 30 minutes
