What Are the Benefits of Testosterone in Stallions?

Stallions are most often found only on horse breeding farms. Stallions have high levels of testosterone, which can make them high-strung, energetic and difficult to control. However, a recent study conducted at the University of Pennsylvania suggests that socialization and exposure to mares has a profound impact on stallion behavior. Those aspects of stallion behavior blamed on high levels of testosterone--energy, strength and volatility--can become positive attributes if stallions are properly cared for.

  1. Energetic Work Horses

    • Unlike geldings, which are much more docile, stallions have enormous energy reserves due to the testosterone in their bloodstream. A study conducted by researchers at the University of Connecticut found that stallions that were forced to exercise every day had lower libidos than the non-exercised control group. For farms where stallions are put to stud for only a few weeks of the year, encouraging stallions to work and burn off their excess testosterone during the non-breeding seasons can channel their energy into productive work that benefits both horses and owners.

    Healthy Bones and Muscles

    • Although horse strength is largely dependent on breed, as a general rule stallions of any breed are stronger and more powerful than gelded males and mares of the same age and breed. As with humans, testosterone in horses is responsible for maintaining bone density and lean muscle. The presence of testosterone in stallions leads to good bone density and enhanced muscle mass. A study published in the Equine Veterinary Journal found that thoroughbred stallions of various ages had greater muscle fiber density than similarly aged mares.

    Leadership

    • Stallions are important members of a herd. In modern horse farm environments, stallions play a less important role, and their inclusion in a herd can be detrimental to a peaceful and domestic environment. However, in farms where horses are left in the pasture or where extensive acreage allows the horses to roam free, stallions are natural leaders and protectors of the herd. High testosterone levels drive reproductive urges, which in turn encourage protective behavior in stallions that are lacking in geldings and mares.

    Breeding

    • The most important role for stallions in modern horse farms is that of studs. Regardless of the personality or effects of a stallion on other horses, stallions--especially those with well-documented bloodlines--are revenue generators for breeders. Well-socialized stallions, particularly those with continual exposure to mares, have high testosterone levels and can breed with large numbers of mares every breeding season. Perhaps more than any other quality, it is their capacity as studs that makes high-strung stallions valuable.