What Are the Callous Like Things on a Horse's Legs?

Horses have different types of body markings that help identify them. One type of body marking on a horse is a callous-like, horny growth, usually called a chestnut, that appears on the inside of a horse's legs.

  1. Appearance

    • Chestnuts, which sometimes also are called "night eyes," look like horny growths or callouses. Each one is shaped differently.

    Location

    • Chestnuts form on the inside of a horse's legs. The exact location varies, depending on whether the front legs or the back legs are involved. The growths appear a short distance above the knee on the front legs. On the rear legs, chestnuts form near the hock, that is a horse's version of the human ankle.

    Significance

    • Chestnuts and night eyes are used to identify horses, distinguishing one from another. Each horny growth is unique. A horse's chestnuts can be photographed for identification purposes. The appearance of a horse's chestnuts also can be recorded by taking an ink imprint in the same way that humans are fingerprinted.