Gelding, also known as castration, is one of the most common elective procedures performed on horses in the UK. As a horse owner, you may already understand the many reasons why castration is carried out: you can tell a gelding, ask a mare, but you must discuss with a stallion, as they say! In this blog, we’ll take a closer look at the different techniques used for the procedure, as well as the potential risks involved, helping you make informed decisions about your horse’s health and care.
When to castrate
Most horses in the UK are castrated between the ages of 6 months and two years. The decision is usually based on the presence of both testes in the scrotum, maturity of the horse and season of the year. We recommend that the surgery is performed in the spring or autumn, during the periods when both mud and flies are at a minimum.
Initial checks before the procedure
Before proceeding with castration, your vet will first carry out a thorough health check to ensure your horse is in good condition with no underlying cardiac issues. A key part of this examination is determining whether both testes have descended into the scrotum. Some horses may be sensitive to handling in this area, making palpation difficult, so sedation is often helpful. In certain cases, a testicle may only become palpable after deeper sedation.
Your vet will also assess for the presence of a hernia, where part of the intestine is present in the scrotum. While rare, this condition increases surgical risk and would require castration to be performed under general anaesthesia.
Another critical factor to consider is your horse’s vaccination status. Ensuring adequate protection against tetanus is essential. Ideally, your horse should have received at least two doses of the tetanus vaccine before the procedure. If a single dose is given at least four weeks prior, it will provide partial protection. While vaccination can be administered at the time of castration, again, protection may not be adequate, and this may leave your horse vulnerable to this potentially fatal disease.
We also need to ensure that the area for us to carry out the procedure is suitable. Ideally, we need a clean, flat, dry area, free from mud or debris. Outdoors is great, with plenty of natural light and fresh air. Having a stable in which the horse can recover is extremely helpful, as is a clean, enclosed area for turnout after surgery.
The castration procedure
There are two main approaches to castration: standing and recumbent surgery.
Standing castration is performed while the horse is heavily sedated, with local anaesthetic injected into the testes and surrounding skin to numb the region. This method is typically quicker and avoids the risks associated with general anaesthesia.
Recumbent castration involves placing the horse under general anaesthesia. Your vet will sedate the horse, insert an intravenous catheter before inducing anaesthesia. While this approach takes longer, it allows for a more controlled surgical environment. Your vet will remain with the horse throughout recovery, ensuring he is fully awake and able to stand safely before leaving.
Which is best?
The choice between standing and recumbent is made by taking several different factors into account. Standing castration is generally quicker, as the horse does not have to recover from a general anaesthetic. However, small ponies, ponies with underdeveloped testes, or those who are particularly anxious about handling may be better castrated under anaesthetic. Older horses and donkeys require special consideration when it comes to castration. Older horses have a higher risk of evisceration, where part of the intestine protrudes from the surgical site, while donkeys are more prone to excessive bleeding. Because of these increased risks, they often benefit from castration performed using surgical techniques best carried out in a recumbent position.
Reported infection rates or postoperative complications are lower under general anaesthesia. However, the benefit comes with an increased financial cost and some risks associated with general anaesthesia such as injury on recovery.
So, what are the risks associated with castration?
The reported rate of intraoperative and postoperative complications in the UK ranges from 10-60%. Many of these complications will be mild, such as postoperative swelling or oedema, but some complications can potentially be very serious or even fatal.
In the immediate post operative period, as the wound is usually left open, some bleeding is normal. Generally, if you can count the drops, this is within normal limits. However, if bleeding continues, or is excessive, please call the team immediately who will be able to assist. We also caution owners to observe the site closely for any tissue protruding. Occasionally, some soft tissue may appear at the edges of the wound and the vets will be able to trim this back. However, there is a small risk that intestine may prolapse through the wound. This is the most serious of complications and must be dealt with as an emergency.
The most common complication is post-operative swelling, which tends to resolve with exercise and Non-Steroidal Anti-inflammatories (NSAIDs). Infection is also not uncommon and can usually be treated with antibiotics and drainage of the site.
Other less common complications include chronic low-grade infection or continued stallion like behaviour.
The vet will discuss these risks before and at the time of surgery, but if you have any questions, please do not hesitate to ask.
What should you expect in the aftercare?
At the time of the castration, the vet will administer an anti-inflammatory painkiller such as phenylbutazone intravenously. They will also prescribe oral anti-inflammatories for a few days. Antibiotics will also be given and may be continued postoperatively if considered necessary.
The vet will be able to give you advice on management based on your horse and your circumstances, but generally, it is a good idea to keep them confined in a clean stable or very small pen for the first 24 hours. Once the horse has recovered, it is a good idea to walk them to keep swelling down. It may be necessary to clean the legs, but you should make sure not to spray water up into the incisions. Fly spray may be necessary depending on the season. It is highly recommended to have somebody available to check on your horse at least twice daily for the first few days. If you have any concerns, no matter how small, please call the practice where our team are on hand to advise and assist.
In conclusion, castration is a routine, necessary procedure frequently performed in practice. Careful planning and proper aftercare are key to minimising risk. While complications are possible, most can be managed when noticed and treated early.
If you have any questions or would like to book your horse in for castration, please contact us at the practice, where the team will be delighted to help.
