Horse, herbivorous animals. In 4000 years ago by the human tame. Przewalski's horse (66 chromosomes) and horses (64 chromosomes) can be crossed with fertile offspring, which in ancient times were the main driving force of agricultural production, transportation and military activities. There are about 200 varieties of horses around the world. With the development of productive forces, the improvement of science and technology as well as the invention and widespread application of power machinery, the role of horses in real life is getting smaller and smaller. Horses are mainly used for equestrian sports and production of breast meat, feeding greatly reduced. However, in some developing countries and regions, the horse is still the main task, and is an important source of force. The staple food of the horse is grass. Horse life of an average of 30 to 35 years old, up to 60 years old.