Surgery of the Equine Female Reproductive Tract Flashcards
Describe the reproductive anatomy/conformation of the vulva
Labia
- Vertically orientated
- 2/3rds vulvar opening below floor of pelvis
Upward orientation of vestibular opening
- If horizontal orientation – contamination
Poor conformation is often acquired: Injury, age, parity, body condition
Name the 3 anatomical barriers – help to stop bacteria/infections getting into the uterus
Vulva
Vestibulovaginal fold
Cervix
List some conformation Problems Contributing to Poor Reproductive Performance in mares (where the surgeon can help)
- Pneumovagina - Caslicks
- Perineal reconstructions - Gadds
- Urovagina - Urethral extension
- Cervical incompetency - Cervical repair
- Delayed uterine clearance - Uterine suspension
- Oviduct blockage - Oviduct lavage, Prostaglandin
Describe the use of the caslicks procedure
Improved vulvar competence; reduced pneumovagina
Describe how to perform the Caslicks procedure
- Stocks / against doorway
- Tail bandaged & held out of the way
- Wash perineum
- Local anaesthesia
- Excise thin band of mucosa each side (3-4mm)
- Include dorsal commissure
- Level with the ischiatic tuber
- Do not oversuture
- Usually 0USP (3.5M) non-absorbable monofilament suture - Remove sutures 10-14 days later
- Remove Caslick before foaling
Describe the uses of perineal body reconstructions
More severe cases of pneumovagina
Second degree perineal lacerations
When is urovaginal most commonly seen?
Urine in the vagina
Usually seen in old, multiparous mares
Often with pneumovagina
How is a diagnosis of urovagina confirmed?
Cytology
How is urovagina treated?
Improve body condition if thin
Surgical management:
- Caudal relocation of the transverse fold
- Urethral extension
When do cervical injuries most commonly occur?
During parturition
How are cervical lacerations treated?
Surgery during dioestrus >3weeks post-partum
Requires good set-up and assistance
Delayed uterine clearance can lead to?
Endometritis
Post mating persistent endometritis
How is delayed uterine clearance treated?
Treatment is uterine suspension (uteropexy)
- Restoration of horizontal orientation of uterine horns
- Improves uterine clearance
- Improves perineal conformation
- May reduce urine pooling
How is an oviduct blockage treated?
Laparoscopic injection of prostaglandin:
- Relaxes smooth muscle of oviduct
- Modulates oviductal transport
Describe 1st degree perineal lacerations
Mucosal damage
Caslick/no surgery required
Describe 2nd degree perineal lacerations
Mucosa, submucosa & perineal muscles
Caslick’s procedure & reconstruction of the perineal body
Describe 3rd degree perineal lacerations
Complete disruption of rectovestibular shelf, perineal body & anus
Faecal contamination
Requires surgical repair
Describe surgery for 3rd degree perineal lacerations
Delay repair for 4-6 weeks
Need swelling to go down
Need to get this mare on a laxative diet
One and two stage procedures described
What is the cause of a rectovestibular fistula
Penetration of foals foot into rectum without progression to 3rd degree perineal laceration
What are varicosities and how is it treated?
Intermittent vulvar bleeding
Blood pooling
Worst at oestrus
Treatment:
- Not always necessary
- Topical treatment with astringent creams
- Ligation
- Cautery
- Laser photocoagulation
Name the most common neoplastic disorder of the ovaries in mares
Granulosa (Theca) Cell Tumour (GCT)
Describe the main features of a Granulosa (Theca) Cell Tumour (GCT)
Unilateral (can be bilateral)
Rarely metastasise
Good prognosis after removal
Behavioural signs:
- Anoestrus / continuous oestrus
- Stallion like behaviour / aggression
How are granulosa cell tumours in mares diagnosed?
- Rectal examination
- Enlarged ovary on affected side
- Contralateral ovary usually small - Transrectal ultrasonography - Distinctive honeycomb like appearance
- Endocrinology
How is endocrinology testing used to diagnose granulosa cell tumours in mares?
↑Testosterone in 50%
↑Inhibin in 85%
↑ Anti-Müllerian Hormone (AMH) in 98%
What is a ‘red bag delivery’ ?
Placenta has prematurely detached from the uterus, foal is no longer sustained
How will a mare with dystocia present?
- Prolonged discomfort & straining
- Straining without appearance of amnion
- Appearance of amnion / head / limb but no further progress
Describe the approach to a mare with dystocia
- Be as quick and thorough as you can!
- Obtain a succinct history
- Clinical exam
Describe how to perform a clinical exam in a mare with dystocia
Time yourself – should take <15 minutes!
Standing / recumbent
What state is the mare in (shock, haemorrhage)?
+/- sedation - xylazine
Bandage the tail
Clean the perineum
Wash your hands and arms
Use adequate lubricant
Establish if foal is alive or not
What are the treatment options for dystocia?
Assisted vaginal delivery
Controlled vaginal delivery
Caesarian section
Embryotomy
Describe assisted vaginal delivery
- Mare is conscious (usually standing)
- Foal delivered using traction +/- ropes
- Similar approach as for cattle & sheep but less room and more straining
- Sedation & epidural
Describe controlled vaginal delivery
- Mare is anaesthetised +/- hindlimbs elevated
- Foetus delivered per vagina
- Can be done on the premises if referral is not an option
- In clinic facilities, the abdomen should also be prepared for a caesarean section
How long should a horse be hospitalised post c-section?
1 week
Is the foal or mare more important to save in a c-section?
- Foal more important than saving the mare (foal priority)
- Chronic disease in the mare
- Deliver foal under anaesthesia then euthanise the mare
- Owners must be aware of the implications of rearing an orphan foal / organise a foster mare
List the possible complications that can occur following dystocia/parturition
- Uterine prolapse
- Uterine rupture
- Uterine haemorrhage
- Invagination / retroflexion of the uterine horn
- Retained foetal membranes
- Cervical tears
- Perineal lacerations / rectovaginal tears
How is uterine prolapse treated?
Replacement under standing sedation / GA
Describe uterine torsion in mares
Uncommon
Diagnosed on rectal palpation
Last 2 months gestation / at parturition
Colic / dystocia
Correction: surgical / rolling
Describe uterine rupture in mares
Clinical signs evident 24 – 72 days post foaling
Clinical signs and treatment depend on size of tear
