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We recommend that colts are castrated from six months to (hopefully!) make them a little calmer and easier to manage. This is done over the winter months to reduce the risk of infection or fly infestation of the surgical wounds during healing.

Castration can be carried out using standing sedation and local anaesthetic, or under general anaesthesia. For standing castration, it is important that both testicles are descended and no other abnormal structures (suggesting a hernia) are felt within the scrotum.

Standing castration is an open procedure, meaning the wounds are left open and no suture

(stitching) material is used, which reduces the risk of infection. The open skin wounds allow

inflammatory fluid to drain which reduces excessive swelling. Open castrations can also be

done under general anaesthetic; sometimes due to surgeon preference, sometimes due to

colt’s size or temperament.

After a standing castration, it is expected that blood will drip a little from the wounds.

This should slowly stop over the following hours. Over the next five days, swelling of the

scrotum usually occurs which reduces about 2 weeks after surgery. This can be managed by

medication with anti-inflammatories such as ‘bute’. It is important to remember that swelling

does not necessarily mean the area is infected. Gentle exercise in the form of daily turn out

can help reduce swelling. Fly repellent in the surrounding area (not in the wounds) may be

required during the warmer months.

Stallion-like behaviour, driven by hormones, can remain for approximately six weeks and

turnout with mares should not begin until at least four weeks post-castration. After this

time, your colt can be treated as a gelding, making management easier.

In older horses, those been working as breeding stallions, or donkeys, the risk of

complications is increased and as such, closed castration is often advised. This is done under

general anaesthetic and sutures (stitches) are placed. This is a more expensive procedure

but it does lessen the risk of complications.

Unfortunately, castration is a surgical procedure that carries quite a high risk of

complications. Knowing what is to be expected after castration means you can identify any

problems early.

Significant bleeding can occur after the sedation wears off and the horse wakes up. If the

drops of blood cannot be counted, or a stream of blood is seen, then the vet will need to

return to assess the surgical wounds.

Due to the nature of the open standing castration, very rarely, herniation can occur and

abdominal contents can protrude from the wounds. Although this is incredibly rare, it is

important to know that it is a veterinary emergency.

Infection is probably the most commonly encountered complication and is seen as excessive

swelling, heat or discharge from the wounds. Sometimes a course of antibiotics is required,

and occasionally, the horse will require additional surgery to remove any infected tissue,

particularly if it is long-standing or severe.

Although castration does carry complication risks, it is a very necessary procedure for most colts and as such, if you’d like to discuss any aspect of your colt’s care, please call us on 01565 723030 to have a chat to one of our vets.


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