When to Geld a Colt: Pros & Cons

Last Updated on May 21, 2020 by Allison Price

Wondering when is the right time to geld your colt? 

  • You can geld a colt from as early as a week old, provided he has both testicles descended. And if you can find a vet willing to geld that young. Many vets recommend waiting until the colt is several months old. They said it will handle the anesthetic better. That brings us back to the question above… When? 
  • To produce a well-behaved and future-focused gelding, castrate your colt before age one. Also gelding your colt makes it easier to handle your horse. If you have a stallion, you’ll need to keep it pastured away from mares to avoid unnecessary breeding. If you don’t want to use your horse for breeding purposes, you should have him gelded at a young age.
  • When it’s time to geld your colt, certain nostalgia, and historical perspective matter. Every breed category will have a different view of when it’s best to geld your colt. They all suggest different stuff. They gelded horses of all ages, even some horses into their teens. Medically speaking, there is no reason to delay castration in most situations. The appropriate time for gelding your colt is a fine line between too young and too mature. The most popular colt gelding is between the ages of six and 12 months.

Gelding a Colt at an Early Stage


  1.  Farm owners usually castrate colts around weaning. This could be anywhere from 4 to 6 months.
  2. Your colt has enough testicular growth at three months of age. This makes the testicles a reasonable size for easy identification and castration. If you’re trying to castrate your colt at an age that’s too young, the testicles aren’t much evolved. It will be harder to identify and sever them.
  3. Many castrations performed under general anesthesia. There is less concern for younger horses when it comes to healing from anesthesia.
  4. The younger the patient, the quicker the periods of recovery. There will be less testicular tissues and smaller scrotums for younger. This requires less time to heal.


  1. Sometimes owners worry that gelding at a young age will slow development and growth. Yes, this can happen when you geld a colt during a growth spurt. It is usually between one and two years old. But, if gelded before a year old, they often grow taller than expected.
  2. An early gelded colt will also have a finer neck and more uniform body muscling. A mature gelded colt or stallion (from 4 to 6 years of age) should have a thicker, crestier neck and heavier muscle. They may also develop sexual or stallion behaviors.
This sometimes equates to vices such as:
  • biting
  • rearing
  • self -mutilation (out of frustration)
  • excitable behavior around other horses
  • And even the ability to serve mares without being a cryptorchid usually known as a rig.
  1. If your colt doesn’t have two descended testicles, you will need to wait for them to both descend. If they haven’t by the age of two, it will mean a major operation to find and remove the undescended testicle.
  2. The surgery could cause death or infection. But that is very unlikely if a professional vet performs the surgery.

Gelding a Colt at a Later Stage:

As far as everyone in this field knows, gelding a colt on its late-stage may only cause many problems. Even if there are a few advantages, let’s start with the CONS. 

  1. Delaying castration beyond one year of age produces a horse that will have stallion-like behavior in the longer-term… AKA “Problems in Stallion.” Stallion is a mature male horse. Part of behaving like a stallion is displaying hormonally charged habits. 

This include:

  • physical violence with peers and with human beings
  • loud and disturbing vocalizations
  • attempts to mount female horses
  • masturbation
  • And often even anxiety-based self-mutilation.
  1. If your horse stays a stallion for only one breeding season (springtime)… even if it is not breeding in general, it will have a long-term effect on his actions. Even after gelding, he will show more stud-like behaviors.
  2. There’s more testicular tissue growth as your colt ages. It also increases blood flow to the testicular region. Increased bleeding and secondary complications are smaller when your geld is younger.
  3. When you are gelding a mature horse, avoiding hormonal activity takes a couple of months. Moderating sexual conduct is to keep them apart from fillies or mares. Semen is also stored in a reservoir. It is not removed during the operation so impregnation may occur for up to a month after gelding.
  4. Once standing and healing from anesthesia, older horses hurt themselves, or their handlers.
Gelding an older horse may stop the impregnation of female horses. But this may not prevent fighting behaviors or the desire to mount, for instance.
  1. If it’s old enough to run through training. I guess it won’t be a problem if we need to educate a colt – to get caught, embrace a halter, lead, and contact the entire body. It’s also helpful to get him used to being sponged with water and hosed gently. Especially around and between the back legs in case major swelling or infection after operation needs to be treated.
  2. It’s possible some may view a castration operation as the ‘un-kindest’ cut. For a horse, the gelding is the ‘kindest cut’ you can give him for a better future… with lots of interaction with other horses and people.

TIPS & GUIDE: Choosing the right time to geld a Colt

  • Many farms would castrate in winter or spring periods before the first year of age of the colt. Insects are less of a problem at this time of the year such as FLIES. And cooler weather should help prevent swelling.
  • The age of colts reaching puberty varies between breeds and within them. The growth plates of the long bones that have the most influence on the horse’s growth close at various times. And these times may vary among breeds.
  • Castrating a horse from the distal part of the radius or tibia, the long bone above the hock, before development starts are likely to increase its height… but whether this increase is likely to be substantial is unknown.
Allison Price
Allison Price

I’m Allison, born and raised in San Diego California, the earliest memory I have with horses was at my grandfather’s farm. I used to sit at the stable as a kid and hang out with my Papa while he was training the horses. When I was invited to watch a horse riding competition, I got so fascinated with riding!