Equine Castration

Question 1

When do we castrate horses?

Answer 1

When both testes are descended

6 months - 2 years

Question 2

How do we choose between open or semi-closed/closed castration?

Answer 2

Open = used for standing field castration, not used in older horses/those used for breeding/donkeys
Semi-closed/closed = requires GA, usually in a hospital/clinic

Question 3

How do we decide between field and hospital castration?

Answer 3

Dependent on facilities of practice and yard
Transportation of horse
Affects technique used

Question 4

How is an open castration carried out?

Answer 4

Incision through skin and vaginal tunic to expose testis

Emasculators applied to vas deferens and testicular vessels

Question 5

Describe emasculators.

Answer 5

Have 2 blades - one cuts, the other crushes
Important to place correctly (“nut to nut”)
Store loosely and then tighten before use

Question 6

How is closed castration carried out?

Answer 6

Incision through skin only
Blunt dissection of vaginal tunic containing testis from surrounding tissues
Ligatures placed before emasculation

Question 7

What are the scrotal options after castration?

Answer 7

Sutured (primary closure)
Left open (second intention) - used in field castration for drainage
+/- ablation

Question 8

Describe standing castration.

Answer 8

Performed under sedation (alpha2-agonist and butorphanol) and LA
Usually young (<18 months) but well-handled horses
Quick, effective, cheap, traditional
Poor asepsis, high incidence of minor complications
Poor options for complication management
Risk of injury to surgeon
Uses open technique

Question 9

How do we prepare for standing castration?

Answer 9

Sedation
Check for presence of two testicles
Scrub scrotum
Local anaesthetic injected into the subcutis and testicle
Rescrub the area
Safe positioning when palpating, prepping and castrating

Question 10

What considerations do we need to have for field GA castration?

Answer 10

Always IV catheter
Safe area for knock down and recovery
Positioned in lateral recumbency - hindlimb held up with lead rope
Everyone out of kick zone/headbutt zone - dorsal spine

Question 11

What should we check before castration?

Answer 11

Age of horse
Tetanus status
Whether it has been used for breeding
Facilities at yard
Two testicles descended
Discussion of costs, risks/complications, procedure

Question 12

What complications can occur?

Answer 12

Swelling
Haemorrhage
Infection - schirrous cord
Tetanus
Evisceration - prolapse of omentum/intestine through inguinal ring (intestine = emergency)

Question 13

What needs monitoring post open castration?

Answer 13

Bleeding - countable drips okay for first 12 hours
Swelling - some expected
Surgical site - monitor for anything protruding
Sedation/anaesthesia - check for colic signs

Question 14

What is the aftercare after a standard open castration?

Answer 14

Box rest for 24-48 hours
In-hand walking 2-3 times daily
Turnout after 7-10 days
Continue with NSAIDs for analgesia

If primary closure of scrotum - box rest
Can still be fertile up to 8 weeks post-op so keep away from mares!