Managing Mares to Optimize Reproductive Efficiency Flashcards
What are the two goals of reproductive efficiency?
-1 live foal from each mare intended for breeding
-1 live foal per insemination or cover
Pregnancy rate =
(# mares pregnant / # mares bred) * 100
Pregnancy rate is:
pregnancy/season or pregnancy/cycle
Live foal rate =
(# of live foals / # mares bred) *100
Live foal rate depends on…
-pregnancy rate
-successful gestation and delivery
Live foals for mare and stallion owners are:
-product for the mare owner (to keep or sell)
-revenue for the stallion owner
Types of stallion contracts:
-no guarantee - mare owner pays up front, no matter the outcome
-live foal - most common; mare owner does not pay unless there is a foal born alive (usually with specific criteria)
-Stands and nurses - mare owner pays once the foal is able to stand and nurse on its own
What is the pregnancy rate season goal?
90%
What is the pregnancy rate per cycle goal?
60%
After about 3 cycles, how many mares will be pregnant?
90%
What is the average live foal rate for all KY TB stallions?
about 68%
What % of live foals is reported for the top 10 TB stallions in KY?
> 75%
-they are intensively manged
-some selection pressure is applied to mares to maximize live foal rate
What is the pregnancy rate on foal heat?
53%
What is the pregnancy rate on 2nd post-partum estrus?
64%
How does birth rate/mating change for mares first bred at 3 to 7 years old?
it does not change
How does birth rate/mating change for older mares and higher number of pregnancies?
it declines
What is the average live foal rate?
75%
When are pregnancies lost?
-early embryonic loss (< 40 days)
-abortion (60-310 days)
-dead foal (>310 days)
-dead mare (anytime during gestation)
What age of mare is the lowest risk for early pregnancy loss?
maiden mares
Placental/umbilical cord abnormality is what % of pregnancy losses?
39%
Placentitis is what % of pregnancy losses?
10%
Other diseases are what % of pregnancy losses?
10 %
Twinning is what % of pregnancy losses?
6%
Still birth at delivery (dystocia?) is what % of pregnancy losses?
13%
Miscellaneous/unknown reasons are what % of pregnancy losses?
22%
Goal for breeding/pregnancies is:
to breed once
Why is it beneficial to breed once?
-mare owner has fewer inputs (visit stallion or shipping semen, fewer vet checks)
-mare will foal earlier next year
-stallion can breed more mares
What is a good/realistic amount of inseminations per pregnancy?
1.5
When should you start teasing a mare?
one month prior to when you want to breed her
What should you do 1-2 days post-breeding?
vet exam for ovulation
What should you do 14-16 days post-breeding?
vet exam for pregnancy (and check for twins)
What should you do 26-28 days post-breeding?
vet exam to check on pregnancy, check for a heart beat and make sure the vesicle is bigger
When can fetal sexing occur?
about 60-70 days post-breeding
