abomasum

anatomy

Also known as: reed

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Last updated

July 23, 2026

Quick Summary

The abomasum is the fourth and final compartment of a ruminant's stomach, often referred to as the "true stomach". Unlike the other three compartments (rumen, reticulum, and omasum), which are specialized for fermenting plant material, the abomasum functions similarly to the stomach in non-ruminant animals like humans.12

It produces acids and enzymes essential for digesting proteins and preparing food for absorption in the small intestine. This system allows ruminants, such as cows, sheep, and goats, to efficiently process fibrous plant matter into usable nutrients and energy.2

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artiodactyl
Digestive system
…derived from the esophagus—and the abomasum (or reed), which corresponds to the stomach of other mammals. The omasum is almost absent in chevrotains. Camels have a three-chambered stomach, lacking the separation of omasum and abomasum; the rumen and reticulum are equipped with glandular pockets separated by muscular walls having sphincters…
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…derived from the esophagus—and the abomasum (or reed), which corresponds to the stomach of other mammals. The omasum is almost absent in chevrotains. Camels have a three-chambered stomach, lacking the separation of omasum and abomasum; the rumen and reticulum are equipped with glandular pockets separated by muscular walls having sphincters…
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ruminant
stomach (the reticulum, omasum, and abomasum), where it is further digested with the aid of various essential microorganisms that live in the stomach. The pseudoruminant digestive process is very similar, also involving regurgitation and cud chewing, though the stomach is divided into three chambers.
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stomach (the reticulum, omasum, and abomasum), where it is further digested with the aid of various essential microorganisms that live in the stomach. The pseudoruminant digestive process is very similar, also involving regurgitation and cud chewing, though the stomach is divided into three chambers.
Read More