LA repro stuff Flashcards
normal bovine estrus length?
behavior length?
24 hr
7 or 12-18 in beef
what is the goal calving interval
13 month
what is the time PP that an animal that a cow is dry
60-80 days
how long do you expose a bull to beef cows
60-75 days
what are three ways to detect estrus
direct observation, detection aids, hormonal assessment
what can affect heat detection
weather, stress, malnutrition
efficiency and accuracy
efficiency is how good you are at catching those in heat
accuracy is are you calling false positives
what is a heat detection rate
bred/eligible in a 21 day period
AM PM rule in ruminants
if she is in estrus in AM, breed in PM
when does ovulation occur once estrus has begun in cows/ewes?
24-32 hours
when does oculation occur once estrus has begun in sows
36-44hrs
what shortens luteal phase?
what lengthens the luteal phase?
prostaglandins shorten
progestins lengthen diestrus
after estrus, when can you lyse the CL using lutalyse
between days 5-17. need mature CL
estrus control. when doing a double injection method how many days apart do you do it? what does this require
11 days. we need people to heat detect so we know when they go into estrus
what is our most commonly used pregestin
CIDR
what do we need GnRH administration for
pushes to ovulate or brings up a new wave of follicles when no CL is present
OV Synch. when do you give what
GnRH- day 0 (reset waves) monday
PGF day 7 (lyse CL) monday
GnRH day 9 (force follicle to ovulate) wed
breed 12 hours later
4 handling times
CO synch. what is it and who for
beef cattle
GnRH- 0
PHG - 7
GnRH AND AI - 9
select synch
GnRH- 0 (monday)
PGF- 7
heat detect BID and AI accordingly for day 6-13
pre synch
PGF to get all CLs lysed
how long are sheep in estrus? goats?
30-36 hr
24-48 hr
main ways we manipulate cycles in sru
photoperiodic treatments
male effect
dormitory effect
in the male effect when do you breed?
introduce male, then silent estrus, then 17-21 days later obvious estrus (breed then)
what is flushing
increase nutrition she that you increase ovulation rates and hopefully cause twinning rates to increase
what is a good way to get early transition ewes to come in
give CIDR for at least 14 days and then remove
how long should male Sru be left out for natural breeding
1.5 cycles
32 days in goats (21d cycle)
27 days in sheep (17d cycle)
when does ovulation occur in estrus of the pig
2/3 of the way through estrus
when is average puberty hit pigs
165 days
what is our estrus synching strategy in pigs
wean after 21 days and estrus will occur 4-7 days later
why are we concerned about synthetic progesterones in pigs
cystic ovarian disease, failure to cycle
when can we lyse the CL of pigs with prostaglandins
after day 12
