The New Student's Reference Work/Ruminant

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Ru′minant, any cud-chewing animal. The animals belonging to this class are grass and herb-eating forms, as the cow, camel, deer, giraffe and sheep. Those living in a wild state are the favorite prey of large flesh-eating animals. In order to crop their food they must go into open, exposed places; but, as mastication is a long, tedious process, they retire to the shelter of concealed positions to ruminate or chew their food properly. The process of chewing the cud cannot be understood without considering the complex stomach of these animals. It consists of four compartments: the paunch, the reticulum or honeycomb bag, the manyplies and the true stomach. The food when first swallowed is in the form of a coarse pellet which pushes aside a fold in the wall of the oesophagus and goes into the paunch. There it is softened and passed into the reticulum, where it is moulded into pellets of convenient size, which are passed up the œsophagus into the mouth by a process the opposite of swallowing. Here they are carefully masticated and mixed with saliva and then swallowed again. The pellet is now smooth and fine; instead of pushing aside the fold in the wall of the œsophagus, it is guided by it into the third stomach or manyplies. This acts partly as a strainer through which the food passes into the fourth compartment or true stomach. Glands in the walls of this part secrete gastric juice and digestion is carried forward. The camels differ from other ruminants in having no third stomach.

Stomach of sheep. (a) Œsophagus; (c) rumen or paunch; (f) abomasum or reed; (b) beginning of duodenum.