Horses are not ruminants, although they are capable of digesting cellulose and other plant-based materials despite lacking a forestomach. The fermentation of plant matter is done in the large intestine, which in horses is massive and complex.
Horses are odd-toed ungulates within the family equidae, which includes zebras and donkeys. The fight-or-flight response of a horse is adept in addition to its sense of balance, making the horse an animal that is quick to flee. Horse breeds are divided into three categories: hot bloods, cold bloods and warm bloods. Hot bloods are used for speed and endurance, while cold bloods are better at slower-paced, heavier work. Warm bloods are a balance of the two, more suitable for activities such as riding.