Equine Breeding Management and AI Flashcards Preview

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Flashcards in Equine Breeding Management and AI Deck (33)
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1
Q

Breeding systems

A
  • pasture
  • hand
  • artificial insemination (not allowed for Thoroughbreds)
2
Q

Types of mares

A
  • wet: foal at her side
  • barren: open for at least one year
  • maiden: never been bred before
3
Q

When to breed?

A
  • male factors
  • female factors
  • history
  • palpation findings
  • US findings
  • teasing
  • when ovulation is eminent
4
Q

Tools

A
  • teasing
  • rectal palpation
  • vaginal speculum exam
  • ultrasound
  • hormone assays
5
Q

Teasing

A

Expose a mare to a stallion to gauge mare’s willingness

  • +/- to score mare’s response
  • allow time to gauge response
  • mare with foal may not react predictably
6
Q

Recorded findings

A
  • cervix
  • RO (right ovary)
  • LO (left ovary)
  • uterus
  • fluid
  • cysts (endometrial cysts)
7
Q

Findings in mare in estrus

A

Large ovary (30-60 mm) that may be soft

  • uterus lacks tone
  • cervix difficult to palpate b/c its flaccid, open
  • pink and edematous cervix that is open on speculum exam
8
Q

Ultrasound findings

A

Follicle of 30 mm or larger

  • ovulation occurs between 35-55 mm
  • follicles grow at rate of 2-4 mm per day
9
Q

Edema in the uterus

A

Wagon wheel look

- increases then disappears before ovulation

10
Q

Endometrial edema is due to ______

A

Rise in estrogen at onset of estrus

  • score 0-3
  • 0 = no edema
  • 1 = slight
  • 2 = moderate
  • 3 = heavy (pathologic)
11
Q

Edema will progress and then regress ________

A

24-36 hours prior to ovulation

  • useful in predicting ovulation
  • 0, 1, 2, 2, 1, ovulation —> days 1-6 of estrus
12
Q

Impending ovulatino

A

Follicle softens

  • hyperechoic rim around follicle
  • becomes pear shaped
13
Q

When to order semen

A
  • follicle is 35 mm
  • endometrial edema is present
  • follicle softening
  • mare displays estrus
14
Q

For best results, breed mare _____

A

12 hrs prior to ovulation to 6 hours post ovulation

15
Q

Evaluate semen motility after ______

A

Warming

- 30% motility min

16
Q

Need to have at LEAST _____ progressively motile sperm

A

500 million

17
Q

What are the 2 sites for breeding?

A
  • uterine body

- deep horn insemination (with frozen semen)

18
Q

Post breeding

A

Evaluate for fluid accumulation (4-24 hours)

  • lavage and/or ecbolics if needed –> done w/ endometritis
  • check for ovulation
  • rebreed if mare fails to ovulate timely
19
Q

Ecbolics increase ______

A

Contractility of the uterus

20
Q

Frozen semen

A

Expect poorer results

  • more intensive management
  • lower per cycle preg rates (30-60%) –> extreme stallion variability
21
Q

Hormone levels

A

Progesterone levels during estrus should be basal (0-0.5 ng/ml)
- use mare side tests for quick results

22
Q

Manipulation of estrous cycles

A
  • AI
  • shortening duration of late transition
  • induction of ovulation
  • synchronization of estrus
  • foal heat breedings
23
Q

Drugs used to manipulate mares

A
  • prostaglandins
  • progestins/progesterone
  • hCG (acts like LH)
  • GnRH analogs (deslorelin)
24
Q

Prostaglandins

A

CL is susceptible by day 6 of cycle

  • 5 mg Lutalyse or 250 ug Cloprostenol (never give IV –> sweating, colic)
  • will not shorten interovulatory interval much
  • always palpate or US the mare prior to giving prostaglandins
25
Q

Progestins

A

Artificially lengthen luteal phase

  • regumate or altrenogest
  • progesterone in oil
  • CIDR’s - inserted vaginally where progesterone is absorbed
26
Q

Progestin use

A

Administer for 10-14 days

  • discontinue use and give PG, mare should then enter estrus
  • variable interval to ovulation (4-12 days)
  • progestins inhibit estrus but not necessarily ovulation
27
Q

Progesterone and Estradiol

A

150 mg progesterone and 10 mg estradiol

  • give IM daily for 10 days
  • give PG on last day of treatment
  • breed on day 19-20
28
Q

P&E inhibits _____

A

Both estrus and ovulation

  • normal cycle resumes after administration
  • infections may cause muscle soreness
  • ovulation occurs on smaller follicles (35 mm)
  • most predictable protocol for mares*
29
Q

hCG

A

Give when growing follicle is 35 mm or larger and there is good edema

  • expect ovulation to occur within 48 hrs
  • repeated doses w/n a season may diminish effectiveness
30
Q

Deslorelin

A

GnRH analogue

  • administer when growing follicle is 32 mm or larger and edema is present
  • expect ovulation within 48 hrs
  • effectiveness does not diminish w/ repeated doses
  • sucromate is only FDA approved product
31
Q

Foal heat

A

First post-partum estrus

  • ovulation on day 8-11 after foaling
  • fertile estrus
  • only way to back a mare up
32
Q

Foal heat breeding

A

Examine mares closely for uterine fluid

  • don’t breed if she is going to ovulate prior to day 10
  • prostaglandins to short cycle after foal heat
33
Q

Expectations

A

Per cycle pregnancy rate of 65-70% is ideal when both mare and stallion are fertile