Cud Cud Cud is a portion of food that returns from a ruminant's stomach to the mouth to be chewed for the second time. More accurately, it is a bolus of semi-degraded food regurgitated from the reticulorumen of a ruminant. Cud is produced during the physical digestive process of rumination. The idiomatic expression "chewing one's cud" means "meditating" or "pondering"; similar expressions such as "he chewed that over for a bit", or "chew on that!" likely have the same derivation. The alimentary canal of ruminants, such as cattle, goats, sheep, alpacas, and antelope, are unable to produce the enzymes required to
Coprophagia serves the same purpose within these animals as rumination (cud-chewing) does in cattle and sheep. Cattle in the United States are often fed chicken litter. There are concerns that the practice of feeding chicken litter to cattle could lead to bovine spongiform encephalopathy (mad-cow disease) because of the crushed bone meal in chicken feed. The U.S. Food and Drug Administration regulates this practice by attempting to prevent the introduction of any part of a cow's brain or spinal cord into livestock feed. Other countries, like Canada, have banned chicken litter for use as a livestock feed. The young of elephants,