What options do I have for castrating my horse?

Castration can be performed by a clean (but non-sterile) traditional method wherein the castration wound is left open to drain and heal. Alternatively, the castration can be performed as a sterile procedure, allowing the surgeon to suture the wound closed. Each procedure has advantages and disadvantages.

In our practice both procedures are performed under a short-acting general anesthetic. In the case of the traditional or open procedure, the skin incision is left open and the wound allowed to heal as an open wound. The horse is rested 24 hours, after which forced exercise is initiated to insure that the wound stays open. Contamination is minimized when the gelding can be turned out on a green pasture.

The amount of forced exercise necessary depends on the stabling or pasture arrangement in which the horse is kept. Stalled horses should be exercised at a trot for 15 minutes four times each day for two weeks. If the horse is in a large paddock, three times daily is usually adequate. Even pastured horses may need forced exercise once or twice daily. The goal is to minimize and control the infection that occurs in all open wounds so that the infection remains superficial and does not invade deeper tissues. As long as the castration wound remains open at the skin level, healing progresses from the deepest part of the wound toward the surface. If, however, the skin seals closed, drainage will accumulate in the wound where bacteria will propagate and invade surrounding tissues.

The closed procedure is performed using sterile technique. The surgical site is scrubbed to provide a sterile surgical field. Sterile surgical drapes, surgical gloves and a sterile surgical instrument pack are required. After the testicles are removed, the deeper tissues are sutured, then the skin. Since the procedure is conducted in a sterile fashion and no open wound is present, infection is not an issue. Horses gelded using a sterile closed technique have minimal swelling, no superficial infection and do not require the intense exercise regimen of the traditional open procedure.

At what age do you recommend castrating a colt?

One thing about horsemen and women, they all have an opinion. The same is true for veterinarians. But since you opened this file, I will give you mine! If I were to choose one age, it would be 12 months. I do not recommend castrating colts less than 6 months of age, but I have no upper limit.

Some foals are born with enlarged inguinal rings. These are the openings through the abdominal wall in the groin area in which the spermatic cord traverses to reach the testicle. When a colt is castrated, the potential exists for intestine to fall through this ring if it is large enough. By waiting until a colt is at least six months of age, this complication is minimized.
The testicles of some youngsters may not be descended into the scrotum. If the testicle is just high, it can be removed with a little additional effort, but if it is inside the abdomen it is a bit more complicated. Removing an abdominal testicle is considered major surgery since the horse must be anesthetized, placed on his back and an incision made into the abdominal cavity. The surgeon then begins a systematic search of the abdomen to find the missing gonad. A veterinarian can usually feel a testicle that is high but not in the abdomen. This exam is best accomplished with light sedation to encourage the horse to be more relaxed and cooperative.

Stallions generally become fertile at two years of age and their testicles continue to grow until five. It is best to get the job done before they get too aggressive. Testosterone is often the underlying cause of a variety of injuries and accidents, so castrating before a problem develops is recommended. Obviously, the larger the testicles the more traumatic the procedure is to remove them. The testicles decrease in size in the winter and enlarge as the natural breeding season approaches each spring.

For more information on the castration procedure see “What options do I have for castrating my horse?”

Your First Visit is FREE

Sign up now

Office Hours


8:30 am-5:00 pm


8:30 am-5:00 pm


8:30 am-5:00 pm


8:30 am-5:00 pm


8:30 am-5:00 pm






Find us on the map


  • "Phenomenal veterinarians and excellent service! I appreciated the care the vets and technicians took for each and every one of my animals. Their attention to detail and concern for the well being of my stock was much appreciated."
    Jamel Perkins / Gilham

Featured Articles

Contact Us