The Cow Digestive System
Many people believe that a cow has four stomachs. However, what they refer to as ‘cow stomachs’ are just different compartments in the digestive system of a cow. A stomach can be defined as an organ where acids, enzymes and other compounds used for digestion are secreted so as to aid in the breakdown of food particles into molecules. It is therefore incorrect to say that there are four cow stomachs since cows basically have one stomach with four compartments. These compartments include reticulum, rumen, omasum and abomasum. Each of these compartments plays a particular role in the digestion of food consumed by a cow.
A cow is classified as a ruminant since it chews cud. This means that it only chews food enough to allow it to swallow. This partially chewed food is stored in the reticulum. In addition, there is collection of ingested particles that cannot pass through the digestive system. When the cow is resting, food stored in the reticulum is brought back into the mouth and chewed more thoroughly. This process is known as chewing cud. After the second chewing the food then goes to the second compartment known as the rumen. In this compartment, fermentation takes place as well as the break down of things such as cellulose, lignin, hemi-cellulose as well as fiber. The food then moves on to the third compartment known as the omasum.
In the omasum the main process that takes place is the absorption of water and some other nutrients that have already been digested in the other compartments. The last compartment is known as the abomasum or the true stomach. Here, enzymes and other digestive juices break down the rest of the food. Some people refer to these compartments as cow stomachs while others consider them an extension of the esophagus since no real digestion takes place here.