Animal World


Why do cows have four stomachs?

The stomachs of cows, as well as all ruminants, are divided into four sections—the rumen, reticulum, omasum, and abomasums. Ruminants eat rapidly and do not chew much of their food completely before they swallow it. The liquid part of their food enters the reticulum first, while the solid part of their food enters the rumen where it softens. Bacteria in the rumen initially break it down as a first step in digestion. Ruminants later regurgitate it into the mouth where they chew their cud. Cows chew their cud about six to eight times per day, spending a total of five to seven hours in rumination. The chewed cud goes directly into the other chambers of the stomach, where various microorganisms assist in further digestion.


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