Beef Cattle Flashcards
at what age should a beef cow have her first baby
2 years
how often should beef cows have a calf
every year
how long is cow gestation in months?
9 months
at what age are calves weaned?
6-7 months
what is the equation for calf crop?
weaned/# cows exposed to a bull
how long is cow gestation in days?
approx 280
how many days is a cow’s estrus cycle?
21
to calve every 365 days, a cow only has _________
one 21 day estrous cycle to get pregnant
who is more fertile: cows or heifers?
heifers
who has a higher dystocia risk: heifers or cows? why?
heifers because they are not yet at their mature body weight and are smaller
what are 3 things you can do for calving management?
- precalving vaccinations
- minimize neg effects of dystocia
- colostrum management
why do we do precalving vaccinations?
it allows for passive transfer of immunity to the fetus to help protect against neonatal calf diseases
list some pros and cons for having a Jan/Feb calving
- weaned calves are larger=more $$$
- coldest part of the year
- labor intensive
- need more feed for dams
list some pros and cons of having a March/April/May calving
- temperature isn’t as cold
- don’t need as much feed for dams
- finished calves are marketed during lower prices=less $$$
- spring storms can cause disease and death for calves
interferes with grain farming
when should you do pre-breeding vaccinations? what else should you do at the same time?
45 days prior to the giant cow orgy
also give anthelmintic treatments
body condition score the entire herd
what are the main diseases we vaccinate against before breeding?
- infectious bovine rhinotracheitis (IBR, also bovine herpesvirus type 1, BHV-1)
- Bovine viral diarrhea type 1 and type 2 (BVD)
how does body condition score effect the re-breeding of cattle after they have calved?
cows in good body condition start cycling again sooner after they’ve calved, compared to cows in thin body condition who take longer to start cycling again after they’ve calved
who do you want to cull, those with larger pelvic size or those with smaller pelvic size?
those with smaller pelvic size–>selecting for larger pelvic size does not prevent dystocia
when doing your reproductive soundness evaluation 6 weeks prior to breeding, what are you looking for? (aka, what do you want, and what do you NOT want?)
not good: immature uterus with no palpable follicles or the follicles are small, freemartinism, is already pregnant, or is skinny
good: not cycling but has palpable follciles and good uterine tone
best: cycling (CL present and/or follicles that are more than 10mm, good uterine tone)
we want heifers to be ___%BW at breeding and ___%BW at first calving
65%, 85%
When selecting replacement heifers, why do you want the ones that are born in the first 42 days of calving season?
heifer calves born in the first 3 weeks will be larger and reach puberty sooner. replacement heifers have an earlier breeding season and they also take longer to start cycling again after having a baby compared to cows. heifers also have a longer lactational anestrus, around 100 days compared to 60 in a mature cow. If you select the heifers that are born sooner it allows you to manage this and sync them up with the cows. (I think????)
why is the breeding season for heifers 30-42 days prior to cow breeding season?
because first calf heifers take longer to come back into heat after they calve, so we do this in order to sync them with the other cows
how long is lactational anaestrus for first calf heifers? compare this to lactational anaestrus for cows?
100 days
60 days
how many days are there between calving and the next pregnancy? how did you get this number?
365-280(gestation)=85 days
