18.3.2: Clinical reproduction Flashcards
When is the ideal age to have a first foal from a mare?
5-7 years
However it is often uncommon to breed at this age because the horse is being ridden
Would you want to breed this mare? If not, why not?
- Hair coat suspicious for PPID
- Not a definite no to breeding but must be taken into consideration
What health tests/ screens must be undertaken before a mare arrives at stud?
- Reproductive pathogens: Taylorella equigenitalis
- This is part of contagious equine metritis and detected via clitoral swab
- Every reputable stud requires this
- Other notifiable diseases should also be screened for in order to have good biosecurity as a stud farm
How do you test for CEM/ Taylorella equigenitalis ?
Clitoral swab
How sound does a mare need to be in order to carry a foal?
She must be pasture-sound at minimum
- Sunken anus -> risk of faecal contamination, air being sucked in and chronic endometritis
- Possibility of urine pooling
- Vulval lips are not properly sealed
- Would manage this with Caslick’s procedure
What structure might you look out for especially when scanning an older mare with no previous breeding history?
Endometrial cysts - these are more common in older mares
1 - Corpus luteum
2 - follicles - could measure these
* Could grade uterine oedema - this is a 0/3
* This mare is in the luteal phase (dioestrus)
* Need to give the mare prostaglandin to lyse the CL
What would you expect this mare’s cervix to feel like?
- This mare is in the luteal phase (dioestrus) and progesterone is dominating
- She would have a toned cervix
- This mare has mutliple follicles (measure these)
- She also has uterine oedema (2/3)
- Her cervix would feel softer and be opening
- She is on day 16/17 of her cycle (early oestrus) -> scan every 1-2 days
This follicle is 35mm. Thoughts?
- Uterine oedema 3/3
- Follicle acquires a tear-drop shape when close to ovulating -> not doing this yet
- Start to consider forcing ovulation by giving GnRH or hCG -> this would ensure ovulation in the next 24-48hrs
What is lifespan of frozen semen?
- Frozen semen = very limited lifespan
- Must meet the egg within 6 hrs
- Could consider using one dose pre-ovulation and another post-ovulation
- Could use ovulation-inducing agents to induce ovulation at a specific time point, and scan mare repeatedly within that time frame
A
32-40 hrs
B
36-42 hrs
How would you expect this mare’s cervix to feel?
Soft and dilated
This is a post-insemination scan. What can you look for?
- There is a corpus haemorrhagicum on the ovary
- Could measure the amount of fluids/ consider oxytocin/ flush if 30mm or more/ endometrial swab and culture in case antibiotics needed
What is the earliest we can detect pregnancy in the mare?
12-15 days
Signs of oestrus in the mare
- Lifted tail head
- Discharge from the vulva
- Clitoral winking
- Behavioural changes (often considered more sassy)
How do you treat post-mating endometritis?
- Uterine lavage
- Oxytocin
- Intra-uterine antibiotics
What should you check at a post-insemination check?
- Quality of CL
- If there have been any secondary ovulations making twins a possibility
- Any signs of post-mating endometritis
How long can fresh semen survive in the mare and when should she be inseminated in relation to ovulation?
- Fresh semen will survive at least 48hrs in the mare
- Insemination is performed before ovulation (12-36hrs perior to expected ovulation; use ovulation-inducing agents to time this)
Which tends to lead to greater post-mating endometritis:
a) fresh/chilled semen
b) frozen semen
b) frozen semen
This is a scan from 15 days post ovulation
- There is a healthy embryo here
- There could be an endometrial cyst or a second conceptus on the LHS -> see if it moves and monitor for growth
- Look for CLs and count them
- If unsure, rescan in the next 1-2 days
A mare has become pregnant with twins and you need to crush one conceptus. What medication might you give the mare beforehand?
- Restraint her in stocks
- Chemical restraint: detomidine + butorphanol
- NSAIDs: flunixin or phenylbutazone
- Could consider buscopan to relax rectum but this will relax uterus as well
