Equine 2

Question 1

why do we manipulate equine breeding

Answer 1

to obtain desired genetics
to match a mare and stallion time wise
to ensure synchronization of donors and recips
to hasten the onset of the breeding season

Question 2

for many competitive breeds, the universal birthdate is

Answer 2

January 1
for a competitive edge, you want to be born as close to January 1st as possible without being December 31st

Question 3

1st step of equine breeding

Answer 3

getting details from owner
examine mare + get history (is she going to carry on her own? ET? Has she had a BSE?

Question 4

if mare presents as dirty in a BSE, what do you need to do

Answer 4

work up

Question 5

rule #1 of breeding is

Answer 5

DONT DO ANYTHING until all the stallion details are sorted and the paperwork is completed and confirmed to be paid

Question 6

3 ways mare can get bred

Answer 6

live cover, cooled semen, frozen semen

Question 7

success rate per cycle for live cover

Answer 7

80-90%

Question 8

artificial insemination: what is process

Answer 8

stallion is collected away from the mare & semen is then extended and shipped to the mare via courier, FedEx, or flight, then placed in uterus using sterile technique

usually only 1 or 2 doses are shipped and semen is viable for 24-28 hours

Question 9

success rate for cooled semen

Answer 9

75%

Question 10

acceptable motility for cooled semen

Answer 10

60% progressively motile

Question 11

frozen semen process

Answer 11

a stallion is collected and semen is frozen in an extender using liquid nitrogen into straws, and semen is purchased by dose, often with no foal guarantee
contract is paid for in advance

Question 12

frozen semen motility acceptable

Answer 12

30% progressive

Question 13

frozen semen success rate

Answer 13

30-40%

Question 14

in frozen semen, the ovulation is scheduled then the mare is inseminated via a flexible pipette into

Answer 14

deep into the uterine horn on the ovulating side - immediately post ov

Question 15

which breeding type has the highest chance of post mating induced endometritis

Answer 15

frozen

Question 16

breeding rule 2

Answer 16

whenever you receive info on a new stallion, call the stallion station to confirm the details. Dont trust the owner, the contract, or the website

Question 17

shipping considerations

Answer 17

what day does the stallion collect?
how many dosages do you get?

Question 18

breeding rule 3

Answer 18

dont make assumptions! keep empty straws if do not need to be returned! Call shipper for confirmation on how doses are to be used!
for cooled semen, ask what the list is like for the day and how many doses they think they’ll ship so you can plan ahead!

Question 19

what are the 10 methods of predicting ovulation?**

Answer 19

1. follicular size for breed of mare
2. follicular growth rate pattern
3. edema pattern
4. days since last OV
5. time since induction agent
6. days since last induction agent
7. irregularity of follicle on ultrasound
8. days since parturition
9. follicular fluid/appearance on US
10. mare’s previous cycle (MOST IMPORTANT)

Question 20

name the follicular sizes of quarter horses, warmbloods, thoroughbreds, drafts

Answer 20

QH: 35-40 mm
warmblood: 40-50
thoroughbreds: 40-45
drafts: 45+

Question 21

REMEMBER THE _________ range should be used as to when you can try to give an induction agent

Answer 21

Upper!

ie - aim for 35 mm to induce a QH

Question 22

follicular growth rate pattern: how many mm do follicles grow per day in peak season

Answer 22

3-5 mm

will stall right before Ov

Question 23

edema pattern will increase with

Answer 23

increasing estrogen

estrogen decreases in the mare prior to ovulation, which means that edema will decrease prior to ov (12-24 hours)

Question 24

days since prostaglandins - mares will come into heat ________ days after prostaglandins, and ovulate in __________ days

Answer 24

4-7, 7-10

however, depends on follicle size when administered and remember that CL must be 5 days old to respond! check before and after administration

Question 25

very small follicles response to PGs? moderate size follicles response to PGs?

Answer 25

may take 7 days or slightly longer to respond classic: after 4-7 days will start to show estrus

Question 26

extremely large dominant follicle response to PGs (3 options)

Answer 26

1) spontaneously OV without estrus - not fertile cycle 2) regresses follicle and begins new follicular wave - will take 10-12 days 3) builds edema in 48 hours and enters heat as normal

Question 27

time since ovulation agent - if giving GnRH agonist, when will ovulation happen? what about hCG?

Answer 27

40 hours, 36 hours

Question 28

days since last ov - mare cycle is average

Answer 28

21 days, with most mares in heat for 4-7 days and out for 14

Question 29

what is the red flag if mare is not following 21 day cycle pattern?

Answer 29

diestrus has to be 14days long. If it's not 14 days long, something lysed the CL and removed P4 block = infection likely!

Question 30

irregularity of follicle on ultrasound - what happens right before ov

Answer 30

follicular wall becomes softer and less turgid in appearance, will often point to ov fossa

Question 31

days since parturition - mares will often ov ____________ days after foaling

Answer 31

7-10

Question 32

foal heat ov - you should check mares 7 days post ov. Mares that have ov prior to this mark are often not ____________. If they hold onto the follicle until 10 days, are they able to be bred?

Answer 32

involuted enough to be fertile. if they hang on until 10 days, they can be bred

Question 33

foal heat breeding rules

Answer 33

mare needs to hold ov until 10 days post ov mare needs to not have dystocia mare needs to not have RP or extreme lochia

Question 34

follicular fluid/wall appearance on US - occasionally you can see sloughing of granulosa cells which will

Answer 34

cause a wall that looks abnormal and thickens and softens

Question 35

follow mare's previous cycle records because that is the most important predictor. Breeding rule 4 is

Answer 35

the mare does what she wants

Question 36

when to order cooled semen?

Answer 36

you should have already called for paperwork/details call when administering PGs or when you think you're a few days out call the day before to pencil in for semen call the morning of to cancel/confirm semen

Question 37

when to induce for frozen semen

Answer 37

time the breeding appropriately for staff you need to be able to do repeat checks throughout day/night need a tight window between ovulation and insemination - within 4-6 hours of ovulation

Question 38

when to induce for cooled semen?

Answer 38

make sure semen is collected and in the box before you induce mare (rule 5)

Question 39

you might hold off on inducing with cooled semen if

Answer 39

mare is super close to ov on her own or anticipating flight/delivery delays

Question 40

reasons you might induce early with cooled semen

Answer 40

a mare with post mating induced endometritis where you need to get timing tight as possible

Question 41

post breeding management - when possible, check mare post insemination to

Answer 41

ensure ov has occurred, check the number of ovulations that have occurred, check for post-insemination fluid

Question 42

if there is post breeding fluid, what should you do

Answer 42

lavage to debunk, ecbolics (NOT PGF2A) to help stimulate fluid, have up to 4 days post ov to treat, remember that semen is safely in the oviduct within 4-6 hours

Question 43

it takes how many days for embryo to get into uterus from horn?

Answer 43

6 days