The Horse, Equus caballus, and the Donkey, Equus asinus

Much of the material on the genetics of the horse and donkey is either old or has been done in Europe and Asia. This is because horse breeding has become relatively unimportant in the United States since the replacement of horses by tractors, trucks, and automobiles. Recently, however, horse breeding has gained importance in the United States because of the pleasure horse assuming an important role in our leisure society.