Cows are ruminants, as well as sheep, goats, bison, deer, antelope, camels. All ruminant stomachs are specially adapted to digest grass and leaves they feed on.
Cows have the perfect mouth for grinding food – large flat teeth at the rear of both jaws. But front teeth cow has only the lower gums. On the upper gums on the front no teeth; only are coated with a thick layer of cartilage. Cow bowed his head, wrapped with tongue bundle of grass and cut it by pressing the lower teeth and fleshy upper gums.
The cow has four stomachs: rumen, reticulum, omasum and abomasum. Each of them is specially adapted for a particular part of the processing of bundles grass and hay that cow eats. Cows chewing grass or hay just until moistened enough to be able to swallow them. Through the esophagus the food goes down to the rumen and reticulum.
Food all the time going up and down. The average cow also spend up to eight hours a day on food rumination. At the end the food passes through the first two of the stomach and enters the other two, where are further decompose, and then passes into the intestine. After that, the food is officially considered to be digested.