Peri-parturient problems in the mare Flashcards
What are pre-parturient problems in the mare?
Colic
*“foal moving”
*Normal gastrointestinal colic
*Colonic infarctions/necrosis
*Uterine torsion
The Over-large Mare
*Ventral oedema
*Pre-pubic tendon rupture
*Hydrops =
- hydrallantois
- hydramnios
*Placentitis
*Varicose veins
*Orthopaedic disease
What are intrapartum problems in the mare?
*Dystocia
*Uterine Rupture
*Uterine tear
*Cervical tear
*Perineal tears
What are post-parturient problems in the mare?
Colic
*Uterine cramps
*Normal gastrointestinal colic
*Uterine haemorrhage
*Colonic torsion
*Uterine horn inversion
*Colonic infarctions/necrosis
Prolapse
*Uterus
*Rectum
*Retained placenta
*Metritis
*Hypocalcaemia
*Tetanus
What is ‘foal movement’ colic?
What should be done?
- Mild / moderate medical colics - caused by intra-uterine movement of foal
- Tx = mild/moderate analgesia = buscopan or phenylbutazone
What is ischaemia/necrosis/rupture of caecum + colon due to?
- Due to weight of foal applying pressure of viscera or stretching visceral blood vessels
- Difficult to diagnose + to treat
When does uterine torsion occur? What is seen?
Dx? Tx?
- Occurs in last third of pregnancy
- Low grade chronic / intermittent colic
- Dx = rectal palpation - one tight broad ligament
- Tx = Surgery, standing flank laparotomy, GA + midline laparotomy
- Rolling under GA
(50% of live foal + 70% of live mare)
Where is the uterine torsion usually?
- Usually cranial to cervix in mares - vaginal exam not helpful
Why do mares get ventral oedema?
*This maybe due to compression of lymphatic
drainage by foal
- no Tx if non-painful + uniform
* differentiate from other causes of abdominal enlargement
What is pre-pubic tendon rupture?
What is seen?
- Due to weight of foetus – more common in older mares
*Large plaque of painful oedema, continuous with udder (“dropped” udder).
*Maybe bloody discharge in milk
*Often gives colic signs
*Mare often spends more time recumbent
What is Tx of pre-pubic tendon rupture?
*Analgesia - bute
*Will need assistance with foaling – cannot use abdominal press.
*Caesarean?
*Will resolve if mare nursed through to foaling, however often progressively becomes more painful and results in euthanasia.
*If survives – do not breed from again
What is hydrops aminion / hydrops allantois?
*Excessive fluid in allantoic/aminotic space
*Up to 200 litres have been recorded
*May eventually cause colic, dyspnoea, recumbency, circulatory collapse.
*Foals usually deformed
How is hydrops aminion / allantois diagnosed / treated?
- Dx = Rectal exam - huge fluid filled uterus but foal out of reach
- Tx = induce foaling / abortion, dilate cervix + drain fluid off slowly, IV fluids to maintain BP
What is the last thing that may cause an over-large mare?
- FAT - sometimes mare = very large near term
- Some mares just Fat and not in foal
- Do rectal to confirm if foal present
What does placentitis lead to?
What are the causes and signs?
- Leads to abortion
- Causes = ascending infection - Strep, E.coli, Aspergillus
- Signs = premature udder development + lactation +/- vaginal discharge
How do you Dx + Tx placentitis?
- Dx =
- Clinical signs
- Ultrasonographic demonstration of placental
thickening - Cervical swabs if discharging
- Treatment =
- Potentiated sulphonamides
- Bute
What is the most common cause of vaginal bleeding in horses?
- Varicose veins - No Tx needed
How are pregnant mares more prone to orthopaedic disease?
- More weight = arthritis / laminitis
- daily use of NSAIDs may be necessary
What would you want with you if you were to go to a dystocia?
- Sedation (and ketamine?)
- Clenbuterol or buscopan
- Local anaesthesia (epidural)
- Doxapram
- Foaling ropes
- Lubricant
- Hibiscrub
- Needles/syringes
- Waterproofs
What would be your approach to dystocia?
- Warn owner – guarded prognosis – may lose both mare and foal
- Restrain mare (sedation? Twitch? Clenbuterol?)
- Quickly check mare not in shock /haemorrhaging. (MM)
- Clean perineum/arms
- Vaginal exam – with plenty of lubricant
- Ascertain presentation/posture/position
9.Decide if vaginal delivery possible
– if not refer for caesarean or euthanise
- if foaling possible – check time
- apply ropes/start traction - If no clear progress within 15minutes
– reassess situation
- consider caesarean
- or controlled vaginal delivery under GA
- Terminal caesarean – GA mare, cut foal out, then euthanise mare
What is a controlled vaginal delivery with dystocia?
- Vaginal delivery under GA
- Hindquarters hoisted
- Can proceed to caesar, terminal caesar or euthanasia
How are uterine ruptures/ tears diagnosed?
- CS
- Rectal / vaginal examination
- Ultrasonography
- Peritoneal tap
What is the Tx of uterine ruptures/tears?
- Medical treat as for peritonitis
- Exploratory laparotomy and repair for full thickness tears
What happens with uterine ruptures?
- In complete ruptures the foal may fall into the abdomen – and not be palpable in the birth canal.
- In these cases the mare may fatally haemorrhage, or will develop fulminating peritonitis and fatal endotoxaemia .
- Extract the foal and consider euthanatising the mare.
- Smaller tears may not be noticed and only suspected when the mare shows sign of peritonitis after foaling. These have a better, but still guarded prognosis.
- Some may not be full thickness
What happens with perineal lacerations? What should be done?
- Minor perineal lacerations are common during foaling.
- Many will heal without intervention.
- Lacerations which substantially disrupt the perineal anatomy should be repaired, especially if natural healing will alter perineal conformation.
- This maybe done immediately, or delayed for a few days if bruising is severe.
- Administer antibiotics/Nsaids/tetanus cover
What is third degree perineal lacerations?
What should be done?
*Where foals foot has penetrated rectum and torn through anus.
*Rectum, vulva and vagina all communicate
*Do not repair immediately – will break down
*Administer antibiotics/Nsaids/tetanus cover
*Repair required if mare to conceive again!
*Delay surgery for 4-6 weeks until granulated in.
*Surgery difficult, several attempts often needed before complete repair occurs.
*Recto-vaginal fistulas – treat in same manner- delayed repair
Until when would you delay repair of cervical lacerations?
- Until uterus involuted + inflammation subsided
(1 month post partum)
What can cause post-partum colic?
- Uterine cramps - post partum uterine contractions (mild/moderate, no endotoxaemia, resolve with bute/buscopan)
- Gastrointestinal colics
- Ischaemia/necrosis/rupture of caecum + colon - expulsive forces
- Inversion of uterine horn - may proceed to uterine prolapse - analgesia + smooth muscle relaxant
What are post partum mares prone to?
- Colonic torsion - sudden increase in abdomen
SURGICAL + rapidly fatal if not treated
What happens with rupture of uterine artery?
*More common in older mares.
*Haemorrhage may occur into broad ligament or into abdomen.
*Mild to moderate colic signs, which may progress to signs of haemorrhagic shock.
*May not respond well to Nsaids – painful?
*May be contained within broad ligament, but if this ruptures or mare is haemorrhaging directly into abdomen then is likely to be rapidly fatal
How is rupture of uterine artery diagnosed + treated?
Diagnosis:
*Gentle palpation of broad ligament per rectum
*Abdominal and rectal ultrasonography.
Treatment:
*Keep quiet – sedate?
*Analgesia
*IV fluids – judiciously
*Blood transfusions
*Clotting agents – amino caprionic acid?, 10ml 10% formalin in 1 litre saline
How does uterine prolapse occur?
*After excessive traction on foal or retained membranes.
*After difficult foaling or if mare exhausted
*May rupture uterine vessels and cause fatal internal
haemorrhage.
*Even after replacement, death from metritis/endotoxaemia not uncommon
How are uterine prolapses treated?
*Clean uterus.
*Replace under epidural anaesthesia.
*Give oxytocin once replaced
*Treat with broad spectrum antibiotics and Nsaids for anti-endotoxic effects
What occurs with retained foetal membranes?
- If left in place the membranes decompose rapidly, produce a metritis which induces endotoxaemia, which may lead to severe laminitis and death.
- However not all mares succumb to the endotoxaemia – some may tolerate RFM very well, whilst others become very sick, very quickly.
- Heavy horses traditionally are considered very susceptible to the effects of RFM
How is retained foetal membranes treated?
*Administer oxytocin (1-2mls =10-20iu), broad spectrum antibiotics, flunixin for anti-endotoxic effects and check tetanus cover.
*Oxytocin alone maybe enough to quickly stimulate passage of the membranes.
*If this does not work then further treatments are highly controversial.
- Manual removal if oxytocin doesn’t work
- Twist placenta if pulling doesn’t work
- If part retained / broke off after checking = LAVAGE + administer more oxytocin
- If signs of endotoxaemia = lavage again in 24hrs
- Maintain Antibiotics / NSAIDs
- Keep lavaging until problem gone
How would you treat metritis?
- Same as RFM - oxytocin, lavage, Ab + NSAIDs
What are signs of hypocalcaemia in mares?
*Muscle fasciculations, recumbency, tetany, Diaphragmatic flutter “thumps”
What is needed straight away with orphan foals?
- A source of colostrum
- A milk replacer
- Bottle/teat
- Feeding protocol
- Foster mare
- FOAL NEEDS A LOT OF MILK - EXPENSIVE
