The females are called mares, the uncastrated males are called stallions, and castrated males are called geldings. Percherons, Clydesdale, and Shire horses are the largest and were originally used to carry knights into battle. Racing horses can achieve speeds of up to 40 miles per hour. At the Virginia Zoo we have two types of Donkeys, or Burros. The average donkey stands about 40 inches at the withers, or shoulders, but different breeds vary greatly.
Colors range from white to gray or black with a dark stripe running from the mane to tail.
They have long ears, which are dark at the base and tip. Although they are much slower than horses, they are very sure-footed and can carry large loads over rough terrain. They are mainly used as beasts of burden and are grazers. Many feral, or wild donkeys, are descendants of animals turned loose from owners and packers. There are two layers of fur, a short wooly undercoat, for keeping the animal warm and long guard hairs to keep out the rain and cold.