Breeding Management Flashcards
What are 3 goals of breeding management concerning mares?
- Maximum number of pregnant mares in a breeding season
- Achieve maximum number of pregnant mares as soon as possible at the lowest cost
- Deliver maximum number of live, healthy foals the following year
What are 2 areas of motivation and constraint that needs to be considered with the breeder?
- Economic
- Sentimental
Which type of factors are easier to change, management or biologic?
Mangament
What are 4 factors for maximizing the chances of getting a mare pregnant?
- Good management
- Clean mare
- Good timing
- Good semen
Are breeding management factors multiplicative or additive?
Multiplicative
What are 6 key factors to obtaining good fertility in the horse?
- Normality of the estrous cycle
- Pre and post-breeding therapies
- Timing of insemination
- Place of insemination
- Number of sperm in the inseminate
- Volume of the inseminate
T/F: When it comes to breeding mares, if you cannot do it right, it is ok to cut corners.
False - If you cannot do it right, then do not do it!
The pregnancy rate equals what?
Number of mares pregnant divided by number of mares bred.
What is the pregnancy rate target for mares per cycle?
Per season?
- Greater than 60% per cycle
- Over 90% per season
TB’s can be bred how often per day?
What is the limiting factor?
- 2-4x per day
- Libido
Stallions collected for AI will get the maximum number of sperm when collected how often?
Every other day throughout the season.
When does uterine edema appear during the estrous cycle in a mare?
What happens after it appears?
- Early in estrus
- Progressive increase
What happens to uterine edema as the mare approaches ovulation?
Approximately when does this start?
- Starts to decrease
- About 24 hours prior to ovulation
Most normal mares will ovulate with a low degree of what?
Endometrial edema
When the cervix is relaxed and edematous, it gives what sort of appearance?
What grade of endometrial edema does this coincide with?
- Fish bone
- Grade 2
What size follicle is usually associated with and endometrial edema grade of 2?
30-35 mm or 40+mm
Some folds are easily observed with hyperechoic centers with what endometrial edema grade?
Grade 2
Folds are thicker with a hypo echoic center and hyper echoic wall with what grade of endometrial edema?
Grade 4
What grade of endometrial edema has a “cart wheel” appearance?
Grade 4
What grade of endometrial edema is considered an abnormal finding and is a state of “hyper-edema?”
Grade 5
If the endometrial folds are very thick to the point they lose their “normal” US structure and have an increased surface area with very little to no free fluid observed, this is considered what grade of endometrial edema?
Grade 5
With grade 5 endometrial edema, how to the follicles appear?
Variable but often pre-ovulatory or recently ovulated.
How does increasing amounts of uterine fluid affect the first cycle pregnancy rate in a mare?
The season pregnancy rate?
Increasing uterine fluid decreases the rate for both.
How long can sperm survive in the oviduct of the mare after natural breeding?
With fresh semen?
Days for both