Horse Breeding

Castration

November 20, 2009

Why gelding your stallion is an important part of responsible horse ownership.

Gelding139

The old adage is true - a good stallion makes an even better gelding.

By Dr. Thomas Lenz in The American Quarter Horse Racing Journal

Because a stallion has the potential to sire hundreds of foals, the decision to geld a colt is especially important.

My father was in the commercial cattle business, and he always said, “It takes a good bull calf to make a good steer.” We always picked out the best bull calf to castrate and show in our 4-H steer classes. I have the same opinion on horses: Generally less than 1 percent of each year’s colt crop is good enough to become breeding stallions.

The second reason to castrate is that stallions are testosterone-driven and can be aggressive and potentially dangerous to other horses and people.

Gelding your colt is one way to make him more marketable. Another way you can do that is to enroll him in the AQHA Incentive Fund. Find out how showing your horse can lead to a big payoff!

Undesirable traits include parrot mouth, cryptorchidism, homozygous HYPP and excessive white with underlying pink skin. We should geld colts that possess any of these undesirable traits. Of course, that decision is only made more difficult if the colt is an extremely good athlete or possesses perfect conformation.

If a colt has a marginal pedigree, possesses undesirable traits or does not possess exceptional breeding potential, he should be gelded early in life, just prior to or after weaning. Some of the advantages of early castration are that the colt never develops stallion-like behavior or secondary sex characteristics such as a cresty neck.

In addition, colts castrated at 4-6 months of age generally experience few post-castration complications such as swelling or infection. I like to castrate colts two or three weeks prior to weaning and then turn them back with their dams where they can get plenty of exercise and a little TLC. I’ve gelded colts as young as 30-45 days of age, and they do fine.

Colts gelded prior to puberty often grow taller than if they were left intact until after puberty. The testosterone surge at puberty (18-24 months) triggers closure of the growth (epiphyseal) plates in the long bones of the legs, and the horse stops growing taller. The theory is that colts gelded at less than 1 year of age do not experience the pubertal testosterone surge and that allows more long bone growth and extra height.

Stay tuned for the conclusion to this article where Dr. Lenz takes you through the castration process and the post-surgical care of your gelding.

Whether you decide to geld your colt or not, make sure to enroll him in the AQHA Incentive Fund. It’s one way showing can lead to a big payoff!