Any large, ruminant, even-toed, hoofed mammal of the genus Bos, family Bovidae, including wild species such as the yak, gaur, gayal, banteng, and kouprey, as well as domestic breeds. Asiatic water buffaloes Bubalus, African buffaloes Syncerus, and American bison Bison are not considered true cattle. Cattle are bred for meat (beef cattle) or milk (dairy cattle).

Cattle were first domesticated in the Middle East during the Neolithic period, about 8000 BC. They were brought north into Europe by migrating Neolithic farmers. Fermentation in the four-chambered stomach allows cattle to make good use of the grass that is normally the main part of the diet. There are two main types of domesticated cattle: the European breeds, variants of Bos taurus descended from the aurochs, and the various breeds of zebu Bos indicus, the humped cattle of India, which are useful in the tropics for their ability to withstand the heat and diseases to which European breeds succumb. The old-established beef breeds are mostly British in origin. The Hereford, for example, is the premier English breed, ideally suited to rich lowland pastures but it will also thrive on poorer land such as that found in the US Midwest and the Argentine pampas.

Of the Scottish beef breeds, the Aberdeen Angus, a black and hornless variety, produces high-quality meat through intensive feeding methods. Other breeds include the Devon, a hardy early-maturing type, and the Beef Shorthorn, now less important than formerly, but still valued for an ability to produce good calves when crossed with less promising cattle. In recent years, more interest has been shown in other European breeds, their tendency to have less fat being more suited to modern tastes. Examples include the Charolais and the Limousin from central France, and the Simmental, originally from Switzerland. In the USA, four varieties of zebus, called Brahmans, have been introduced. They interbreed with B. taurus varieties and produce valuable hybrids that resist heat, ticks, and insects. For dairying purposes, a breed raised in many countries is variously known as the Friesian, Holstein, or Black and White. It can give enormous milk yields, up to 13,000 l/3,450 gal in a single lactation, and will produce calves ideally suited for intensive beef production. Other dairying types include the Jersey and Guernsey, whose milk has a high butterfat content, and the Ayrshire, a smaller breed capable of staying outside all year.

Breeding
Aided by the development of mathematical genetics, many countries have evolved large-scale breeding schemes for cattle, aimed at maximizing economically important characteristics, particularly in dairy cattle. Artificial insemination has had a remarkable impact on the cattle industry during this century, obviating the need for small producers to keep bulls, and substantially increasing the number of cows mated to one bull. In consequence fewer bulls need to be retained for mating, thus allowing more stringent selection, and the best bulls are made available to all.

Milk production
The birth of the calf is a central feature of the process of milk production, since it marks the beginning of lactation. The cow first calves at between two and three years of age, depending on the breed and environmental conditions; small breeds, like the Jersey, calve at a much earlier age than bigger breeds like the Friesian. Efficient milk production depends very much on good feeding; cattle generally graze on pasture in the summer, and during the winter are fed a balanced milk production ration plus roughages such as hay and silage.

Beef production
Many calves, in countries with large numbers of dairy cattle, such as the UK, are slaughtered when they are a few days old. A small proportion of calves in some countries is kept longer and fed intensively to produce veal. The remaining calves not needed for replacing the dairy cows that have reached the end of their useful life are fed and slaughtered to produce beef. Intensive indoor feeding methods are a feature of beef production in many countries, and in some cases cereals form almost the whole of the diet.

Diseases
The most serious disease to affect cattle is bovine spongiform encephalopathy (BSE), which attacks the nervous system. Notifiable infectious diseases of cattle include anthrax, foot and mouth, rinderpest or cattle plague, and tuberculosis.

Brucellosis is a bacterial disease, now largely eradicated in the west, which is transmissible to humans. Disorders in the body chemistry (metabolic diseases) of cattle include milk fever, caused by low blood calcium resulting from the demands of pregnancy and lactation; grass staggers (or hypomagnesaemia), caused by low blood magnesium; ketosis, an increase in ketone bodies in the blood early in lactation; bloat (or hoven), caused by eating too much fresh grass or clover. Several parasites, including the warble fly and thread-worm, attack cattle, causing parasitic diseases. Ringworm is a fungal disease of the skin that is transmitted by contact.