Gelding

A gelding is a castrated horse or other equine, such as a donkey or a mule. Castration, as well as the elimination of hormonally driven behavior associated with a stallion, allows a male horse to be calmer and better-behaved, making the animal quieter, gentler and potentially more suitable as an everyday working animal. As a verb, "gelding," or "to geld," refers to the castration procedure itself.

The word comes from the Old Norse geldr ("barren").

The Scythians are thought to have been the first people to geld their horses. They valued geldings as war horses because they were quiet, lacked mating urges, were less prone to call out to other horses, were easier to keep in groups, and were less likely to fight with one another.

A male horse is often gelded to make him better-behaved and easier to control. Gelding can also remove lower-quality animals from the gene pool. Ideally, horse breeders choose to leave only their best animals as stallions; lesser specimens are gelded, to improve the overall quality of the breed.

To allow only the finest animals to breed on, while preserving adequate genetic diversity, only a small percentage of all male horses should remain stallions. Mainstream sources place the percentage of stallions that should be kept as breeding stock at about 10%, while an extreme view states that only 0.5% of all males should be bred. In wild herds, the 10% ratio is largely maintained, though via a different mechanism, as a single stallion usually protects and breeds a herd which is seldom larger than 10 or 12 mares, though may permit a less dominant junior stallion to live at the fringes of the herd. There are more males than just herd stallions, but unattached male horses group together for protection in small all-male "bachelor herds," where, in the absence of mares, they tend to behave much like geldings.

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