Managing Mares to Optimize Reproductive Efficiency

Question 1

What are the two goals of reproductive efficiency?

Answer 1

-1 live foal from each mare intended for breeding
-1 live foal per insemination or cover

Question 2

Pregnancy rate =

Answer 2

(# mares pregnant / # mares bred) * 100

Question 3

Pregnancy rate is:

Answer 3

pregnancy/season or pregnancy/cycle

Question 4

Live foal rate =

Answer 4

(# of live foals / # mares bred) *100

Question 5

Live foal rate depends on…

Answer 5

-pregnancy rate
-successful gestation and delivery

Question 6

Live foals for mare and stallion owners are:

Answer 6

-product for the mare owner (to keep or sell)
-revenue for the stallion owner

Question 7

Types of stallion contracts:

Answer 7

-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

Question 8

What is the pregnancy rate season goal?

Answer 8

90%

Question 9

What is the pregnancy rate per cycle goal?

Answer 9

60%

Question 10

After about 3 cycles, how many mares will be pregnant?

Answer 10

90%

Question 11

What is the average live foal rate for all KY TB stallions?

Answer 11

about 68%

Question 12

What % of live foals is reported for the top 10 TB stallions in KY?

Answer 12

> 75%
-they are intensively manged
-some selection pressure is applied to mares to maximize live foal rate

Question 13

What is the pregnancy rate on foal heat?

Answer 13

53%

Question 14

What is the pregnancy rate on 2nd post-partum estrus?

Answer 14

64%

Question 15

How does birth rate/mating change for mares first bred at 3 to 7 years old?

Answer 15

it does not change

Question 16

How does birth rate/mating change for older mares and higher number of pregnancies?

Answer 16

it declines

Question 17

What is the average live foal rate?

Answer 17

75%

Question 18

When are pregnancies lost?

Answer 18

-early embryonic loss (< 40 days)
-abortion (60-310 days)
-dead foal (>310 days)
-dead mare (anytime during gestation)

Question 19

What age of mare is the lowest risk for early pregnancy loss?

Answer 19

maiden mares

Question 20

Placental/umbilical cord abnormality is what % of pregnancy losses?

Answer 20

39%

Question 21

Placentitis is what % of pregnancy losses?

Answer 21

10%

Question 22

Other diseases are what % of pregnancy losses?

Answer 22

10 %

Question 23

Twinning is what % of pregnancy losses?

Answer 23

6%

Question 24

Still birth at delivery (dystocia?) is what % of pregnancy losses?

Answer 24

13%

Question 25

Miscellaneous/unknown reasons are what % of pregnancy losses?

Answer 25

22%

Question 26

Goal for breeding/pregnancies is:

Answer 26

to breed once

Question 27

Why is it beneficial to breed once?

Answer 27

-mare owner has fewer inputs (visit stallion or shipping semen, fewer vet checks)
-mare will foal earlier next year
-stallion can breed more mares

Question 28

What is a good/realistic amount of inseminations per pregnancy?

Answer 28

1.5

Question 29

When should you start teasing a mare?

Answer 29

one month prior to when you want to breed her

Question 30

What should you do 1-2 days post-breeding?

Answer 30

vet exam for ovulation

Question 31

What should you do 14-16 days post-breeding?

Answer 31

vet exam for pregnancy (and check for twins)

Question 32

What should you do 26-28 days post-breeding?

Answer 32

vet exam to check on pregnancy, check for a heart beat and make sure the vesicle is bigger

Question 33

When can fetal sexing occur?

Answer 33

about 60-70 days post-breeding