Common first opinion reproductive cases in equine practice Flashcards
Name some common equine reproductive conditions
- Post-castration complications
- Protocols for facilitating early foaling
- In-/subfertility
- Twinning
- Abortion
- Dystocia
- Post-foaling colic
- Ovarian neoplasia
- Post-parturient problems in the foal
- Angular limb deformities
This mare was observed in oestrus and is presented for breeding. This ovary is 7-9cm in diameter
- Describe the ultrasonographic features of the ovary
- What do these findings suggest?
- What other changes in behaviour might you see
- How would you confirm diagnosis?
- What is the effect of this condition on fertility?
- How might the condition be treated?
- What are the likely effects on future cyclicity?
- There looks to be some luteal tissue
- There are some little follciles – not the size and shape we would expect to see in a mare showing oestrus signs really
- Ovary 9cm in diameter – quite big!
- Other ovary in this mare was very small
- Other than oestrous
- They either show persistent signs of oestrous that don’t go away or they can show aggressiveness, stallion like behaviour – to others mares or geldings. Depends on what cells are involved.
- Significant ovarian enlargement – granulosa cell tumour
- They can sometimes be very large indeed
- Very large and very small ovary can be indicative – alongside the changes in behaviour
- Diagnosis – they produce other hormones also and the higher sensitive and specificity is anti-malaria hormone. Measure this. Less than 4 is normal, above this is consistent with granulosa cell tumour
- No follicles that are reaching size or ovulating
- Remove the affected ovary – depends on the size how you do this. 3 ways – through vaginal wall, standing flank or midline if very large
- If after it – her other ovary should hopefully start producing again once the hormonal influence has been removed on it
What can produce anti-malaria hormone?
Granulosa cell tumour
they produce other hormones also and the higher sensitive and specificity is anti-malaria hormone. Measure this. Less than 4 is normal, above this is consistent with granulosa cell tumour
What are the likely effects of a granulosa cell tumour on future cyclicity?
If after it is removed – her other ovary should hopefully start producing again once the hormonal influence has been removed on it
Explain what a granulosa cell tumour actually is
A granulosa cell or follicular cell is a somatic cell of the sex cord that is closely associated with the developing female gamete (called an oocyte or egg) in the ovary of mammals.
What are theca cells?
What is their role?
Theca cells are a group of endocrine cells in the ovary made up of connective tissue surrounding the follicle that has many diverse functions during folliculogenesis.[1] These roles include synthesizing androgens, providing signal transduction between granulosa cells and oocytes during development by the establishment of a vascular system, providing nutrients, and providing structure and support to the follicle as it matures.
You are asked to examine this mare 6 hours post unassisted foaling
What is your diagnosis?
How would you manage this case?
- RFM – retained fetal membranes
- They should usually pass these often instantaneously, almost always within 2h
- Don’t really know why RFM occurs
- Predisposition in draft mares
- What should we do?
–If it stays in place, will start to degrade and will have contamination of uterine environment – so nice place for metritis to develop! If we then get systemic involvement, get SIRS and other complications etc.
–You can try to manually remove it, but they are friable – degrades quickly. Have to be careful about causing haemorrhage
–Will she need sedation? Possibly… keep them still and cooperative. Helpful to have good handler holding the mare and someone with the foal as well as the thing that will panic the mare is if foal is not in sight
–Probably use some alpha 2 combined with an opioid, usually butorphanol
–After sedation and foal calm, we should next do a vaginal exam and have a feel – would need to wash back end, tie up her tail and bandage. Then have a feel internally and can usually feel through cervix and into uterus first and feel how well its involuting, can you reach to proximal extent? Most common site for it to be retained is the tip of the non-gravid horn
–Want to encourage to remove itself so want some sort of weight – soaked tea towel tied to the end, fold up placenta so isn’t hanging around foal and her legs.
–Pass catheter into uterus, use tap water or ideally 5L sterile bags of fluid – volume is the most important thing. Can get up to 10L in! syphon it back out until what you lavage out becomes clear
–Then to help get uterus to contract give oxytocin – dose and route is quite personal preference. Give 2ml IM roughly every 2-4h – can cause quite significant uterine contractions and can make them a bit colicky! So likely to want to give them some NSAIDs also such as flunixin. Keep doing this depending on how dirty the mare is, usually 3x per day until the placenta comes away
–If 24-36h down the line, might give a gentle squeeze – turn to see if it will come away but be very careful with this!!
A mare had RFM, the placenta is passed after 12 hours.
How will you proceed with the case?
Is fertility affected?
–Whilst you have active metritis, she wont be cycling or fertile and often does delay foal heat
–Shouldn’t cause problems in future
- Might need to lavage uterus a couple of times after its come away – look at placenta and check you have both of the tips
- Antibiotics intra-uterine often aren’t as effective as large uterus, lots of fluid etc. – if she is systemically unwell, she will get them systemicall
In general, what is the rough treatments for retained fetal membranes?
- No manual removal
- Broad spectrum Abs
- NSAIDS
- Lavage (must get all fluid back)
- Oxytocin 10-20 IU IV q30-120 mins
- Weigh down
- Anti SIRS tx ice feet, pentoxyphyline phospodiesterase inhibitor increases cAMP. Decreases TNF and leukotriene production
- Will affect foal heat only
You are in your first week in practice and you are sent to a stud to go and ‘wash-out’ two mares post-covering
- What does this term mean?
- What will you ‘wash’ this mare out with and why?
- Treating post-breeding endometritis to some degree, some degree is normal after any mating or AI – it is natural process that uterus becomes slightly inflamed to help clear any dead sperm cells or seminal fluid – so it should clean itself up prior to embryo arriving. However in some mares, mostly older, with poor conformation etc. – fluid collects at lowest point – so gravity doesn’t work well. Can also be problems with the cervix. Fluid can be trapped in there
- We are going to treat them depending on depth of fluid
–If under 1cm – oxytocin only maybe
–Should also have results from endometrial swab (as part of BSE) so we know if and what antibiotics we need
–If more than 1cm – tend to wash them out with sterile saline, more important to use sterile as she has just been inseminated and hopefully going to get fertilised embryo arriving at day 5 post ovulation
–Use 1 L bags of saline or Hartman’s – put catheter through cervix with cuff, attach bag, run litre of fluid in, drop bag in and the fluid runs out and collects back in bag – can then look at fluid in bag and see how clear it is. Repeat process over and over again until clear. Prognostic indicator if getting to 5 or 6 L of fluid to get it clean – unlikely to get as good fertility in this mare as one that was clean after the first L
–Intrauterine antibiotics – always use these if been into the uterus with catheter several times, even if nothing on culture, as stables aren’t clean!
•See mare every day up until cleared the fluid. The more days she need washing out the lower the chance of pregnancy. Just keep washing, oxytocin etc. – ridden exercise often helps
6 year old Appaloosa mare running with a stallion for the last 3 months.
Ultrasound reveals:
What to do next?
Further advice?
- Is this a pregnancy? Yes
- Twin pregnancy
- Could be anywhere from 0-3 months in foal – from this US, estimate she might be at 30d scan – can see embryo (2 together) and if was moving, would see a heart beat.
- Problem is is that there are 2 embryos developing
- Would estimate that she day 28-30
- Twins are a problem in mares – their placenta cannot support 2 pregnancies
- Can get late term abortion when they run out of placenta to share between them
- Normally, would do a twin squash – have vesicle and fluid and at day 15, they are quite mobile, implantation doesn’t occur until day 17 – so 2 day window from scan to implant to squash one of them. Can use US guidance to move them apart, put pressure on it rectally and try to crush it on pelvis. Usually feel them squash – and instead of vesicle, there is just 1 normal pregnancy and free fluid within uterus.
- Implantation has occurred here and they have implanted on top of each other! Hard to separate. What are we going to do?
- Give dose of prostaglandin, might need multiple doses – 1 or 2 doses should be enough
- Is she then going to cycle? Yes if its before day 35, she should od – often get delayed return to oestrous but at day 35 get cup formation, and production of eCG, meaning that the mare wont return to cycling that breeding season – so important if we are going to do something we do it before day 35!
- If owner doesn’t want to abort them – cannot really just leave them… likelihood is that 80% of cases have 2 dead foals and often end up with huge vet bill! In practice, still try to squash one of them – going to abort them both anyway really. Might as well have a go as nothing to lose.
- Advice owner going forward – she needs checking more than 3 months later! Could be easily resolved earlier on
When is the earliest we can US for a pregnancy?
What do we see at days 9-12 of US pregnancy scan?
- D10 earliest U/S
- D9-12 round structure, mobile
What do we see at day 18 of an US pregnancy?
What do we see at day 21?
- D18 hypertrophy of dorsal uterine wall -> triangular appearance
- D21 embryo develops ventrally
What do we see at day 23-25 of an US pregnancy?
What do we see at day 30?
- D23-25 heart beat, allantois
- D30 allantois ventral ½ of vesicle
What do we see at day 40 of an US pregnancy?
What do we see at day 50?
- D40: allantois most of vesicle (embryo in dorsal quarter)
- D50: umbilical cord lengthened, embryo descended to floor of allantoic sac