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Not Doing Well after Castration

Code Red - Call Your Vet Immediately, Even Outside Business Hours

Code Red - Call Your Vet Immediately, Even Outside Business Hours

    Castration is a routine surgical procedure, but complications can happen, so those involved must take it seriously.

    The inguinal canal through which the spermatic cord runs is in direct connection with the abdominal cavity, the space surrounding the abdominal organs. This structure is exposed and cut during castration. So a disease process involving this structure can quickly extend up into the belly and become life-threatening.

    It is nearly impossible to predict if postoperative complications will occur.

    The most common complications include:

    BLEEDING. Excessive post-operative bleeding after castration is more common in horses that have a clotting abnormality or very large testicular blood vessels, but is always possible. Excessive bleeding post-castration is more common in donkeys and mules. It certainly will occur if the vessels are not properly crushed.

    However, when properly performed, most horses bleed very little and bleeding is always minimal after 1 hour following the procedure. Excessive bleeding is primarily a problem that is seen during the first 24 hours after castration. If your horse is bleeding more than 1 hour after the procedure, monitor the situation for a few minutes. If it continues or seems rapid to you, call your vet immediately.

    INGUINAL HERNIA. In some horses, the opening in the abdominal wall (inguinal canal) through which the testicles descend into the scrotum is larger or more flexible. In these horses, the intestines and other abdominal tissue can pass through the inguinal opening and come out the incision (called herniation).

    Although inguinal hernias are uncommon, they are a life-threatening complication and must be dealt with immediately and properly. If you notice anything abnormal hanging from the incision, call your vet immediately.

    INFECTION. The incisions are not sutured and are allowed to heal from the inside out. If the incision closes prematurely, infection can be sealed inside. Post-castration infection usually causes excessive swelling of the scrotal area and sheath and a depressed attitude and appetite. Horses with infections will often have a fever over 101.5 degrees. This complication is most often seen 2-7 days after castration but can occur anytime.

    PREGNANCY. A recently castrated gelding can still get a mare in foal for some time after castration because of sperm remaining in the conducting system of the urogenital tract. Recently castrated geldings should be kept away from females for at least 30 days.

    Recently castrated geldings should always have an appetite and fairly normal attitude. They may be a little stiff moving for the first few days but should be willing to move forward. If you have any questions about your horse following castration, immediately contact your vet.


    If you wonder how your horse is doing post-castration, always perform the Whole Horse Exam (WHE). Pay particular attention to rectal temperature, heart rate, attitude and demeanor, and amount of swelling and drainage from the castration incisions.


    Your vet will have probably discussed all of these potential complications with you. If there is concern that the horse is not doing well post-castration, they will assesses general health and inspect the surgical site to determine if there is a problem and if so, what can be done about it.

    What Not To Do

    Do not let anyone other than a licensed equine veterinarian castrate your horse. Complications can be life-threatening and non-vets are usually not equipped to address these problems.

    Likewise, in most if not all States, it is illegal for anyone other than a licensed vet to accept money for castrating your horse. I have seen too many catastrophes brought on by botched castrations performed by non-veterinarians.

    Do not assume that bleeding will stop. Horses can bleed to death after castration. Do not use anything external to try to stop bleeding or treat an infection. Examples I have see include to the topical use of kerosene, motor oil, flour and sugar. The problems are internal and mechanical and cannot be solved this way.

    Helpful Terms & Topics in HSVGWritten, Reviewed or Shared by Experts in Equine Health

    Author: Doug Thal DVM Dipl. ABVP


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