LIVESTOCK FARMING

raising of animals for use or for pleasure. In this article, the discussion of livestock includes both beef and dairy cattle, pigs, sheep, goats, horses, mules, asses, buffalo, and camels; the raising of birds commercially for meat or eggs (i.e., chickens, turkeys, ducks, geese, guinea fowl, and squabs) is treated separately. For further information on dairy-cattle breeds, feeding and management, see dairying. For a discussion of the food value and processing of meat products, see the article meat processing. For a further discussion of breeds of horses, see the article horse: Breeds of horses. An efficient and prosperous animal agriculture historically has been the mark of a strong, well-developed nation. Such an agriculture permits a nation to store large quantities of grains and other foodstuffs in concentrated form to be utilized to raise animals for human consumption during such emergencies as war or natural calamity. Furthermore, meat has long been known for its high nutritive value, producing stronger, healthier people. Ruminant (cud-chewing) animals such as cattle, sheep, and goats convert large quantities of pasture forage, harvested roughage, or by-product feeds, as well as nonprotein nitrogen such as urea, into meat, milk, and wool. Ruminants are therefore extremely important; more than 60 percent of the world's farmland is in meadows and pasture. Poultry also converts feed efficiently into protein; chickens, especially, are unexcelled in meat and egg production. Milk is one of the most complete and oldest known animal foods. Cows were milked as early as 9000 BC. Hippocrates, the Greek physician, recommended milk as a medicine in the 5th century BC. Sanskrit writings from ancient India refer to milk as one of the most essential human foods. Additional reading The Animal Agriculture Series consists of several works by one author, each devoted to a specific class of farm animale.g., M.E. Ensminger, Beef Cattle Science, 6th ed. (1987); other volumes treat dairy cattle, sheep, swine, poultry, and horses, and each is copiously illustrated, covering all aspects of production. Other texts addressing the livestock mentioned in this article include A.L. Neumann and Keith S. Lusby, Beef Cattle, 8th ed. (1986); Tilden Wayne Perry, Beef Cattle Feeding and Nutrition (1980); J.L. Krider, J.H. Conrad, and W.E. Carroll, Swine Production, 5th ed. (1982); Colin T. Whittemore, Pig Production: The Scientific and Practical Principles (1980); Elwyn R. Miller, Duane E. Ullrey, and Austin J. Lewis (eds.), Swine Nutrition (1991); Ron Parker, The Sheep Book: A Handbook for the Modern Shepherd (1983); Allan Fraser and John T. Stamp, Sheep Husbandry and Diseases, 6th ed. rev. by J.M.M. Cunningham and John T. Stamp (1987); G.J. Tomes, D.E. Robertson, and R.J. Lightfoot, Sheep Breeding, 2nd ed. rev. by William Haresign (1979); David Mackenzie, Goat Husbandry, 4th ed. rev. and edited by Jean Laing (1980); and Donald E. Ulmer and Elwood M. Juergenson, Approved Practices in Raising and Handling Horses (1974). Wesley Patterson Garrigus The Editors of the Encyclopdia Britannica