Cows have one stomach with four separate sections rather than four individual stomachs.

Cows belong to a group of animals called ruminants. This group also includes sheep, deer, and giraffes. Their digestive system starts in the rumen, which is the largest section. It can hold up to 50 gallons of food and liquid.Inside the rumen, billions of tiny microbes break down the tough parts of plants. The second section is the reticulum. It helps trap things the cow should not have eaten, like small stones or pieces of wire. The reticulum also helps form small clumps of food called cud.Cows bring this cud back up into their mouths to chew it again. This extra chewing breaks the grass into even smaller pieces. The third section is the omasum. It acts like a sponge to soak up water and nutrients from the food.The final section is the abomasum. This is called the true stomach because it uses acid to digest food just like a human stomach does. A cow may spend 8 hours every day chewing its cud. This process lets cows get vitamins and energy from grass that humans cannot digest.