[1] The alimentary canal of ruminants, such as cattle, giraffes, goats, sheep, alpacas, and antelope, are unable to produce the enzymes required to break down the cellulose and hemicellulose of plant matter.
The function of rumination is that food is physically refined to expose more surface area for bacteria working in the reticulorumen, as well as stimulation of saliva secretion to buffer the rumen pH.
When food has been degraded sufficiently it passes from the reticulorumen through the reticulomasal orifice to the omasum followed by the abomasum to continue the digestion process in the lower parts of the alimentary canal.
Some dairy cows in intensive systems of milk production may have sub-acute acidosis because of the high rates of cereals in their diets relative to an insufficient amount of forage.
[3][additional citation(s) needed] Jewish dietary laws state that an animal that chews the cud and has a cloven hoof is acceptable for consumption.