Cattle

Cattle (Bos taurus) are large, domesticated, bovid ungulates widely kept as livestock. They are prominent modern members of the subfamily Bovinae and the most widespread species of the genus Bos. Mature female cattle are called cows and mature male cattle are bulls. Young female cattle are called heifers, young male cattle are bullocks, and castrated male cattle are known as oxen or steers.

Cattle are commonly raised for meat, for dairy products, and for leather. As draft animals, they pull carts and farm implements. Cattle are considered sacred animals within Hinduism, and it is illegal to kill them in some Indian states. Small breeds such as the miniature Zebu are kept as pets.

Taurine cattle are widely distributed across Europe and temperate areas of Asia, the Americas, and Australia. Zebus are found mainly in India and tropical areas of Asia, America, and Australia. Sanga cattle are found primarily in sub-Saharan Africa. These types, sometimes classified as separate species or subspecies, are further divided into over 1,000 recognized breeds.

Around 10,500 years ago, taurine cattle were domesticated from wild aurochs progenitors in central Anatolia, the Levant and Western Iran. A separate domestication event occurred in the Indian subcontinent, which gave rise to zebu. There were over 940 million cattle in the world by 2022. Cattle are responsible for around 7% of global greenhouse gas emissions. They were one of the first domesticated animals to have a fully-mapped genome.

The term cattle was borrowed from Anglo-Norman catel (replacing native Old English terms like kine, now considered archaic, poetic, or dialectal), itself from Medieval Latin capitāle 'principal sum of money, capital', itself derived in turn from Latin caput 'head'. Cattle originally meant movable personal property, especially livestock of any kind, as opposed to real property (the land, which also included wild or small free-roaming animals such as chickens—they were sold as part of the land). The word is a variant of chattel (a unit of personal property) and closely related to capital in the economic sense. The word cow came via Old English cū (plural cȳ), from Proto-Indo-European *gʷṓws (genitive *gʷéws) 'a bovine animal', cf. Persian: gâv, Sanskrit: gó. In older English sources such as the King James Version of the Bible, cattle often means livestock, as opposed to deer, which are wild.

Cattle are large artiodactyls, mammals with cloven hooves, meaning that they walk on two toes, the third and fourth digits. Like all bovid species, they can have horns, which are unbranched and are not shed annually. Coloration varies with breed; common colors are black, white, and red/brown, and some breeds are spotted or have mixed colors. Bulls are larger than cows of the same breed by up to a few hundred kilograms. British Hereford cows, for example, weigh 600–800 kg (1,300–1,800 lb), while the bulls weigh 1,000–1,200 kg (2,200–2,600 lb). Before 1790, beef cattle averaged only 160 kg (350 lb) net. Thereafter, weights climbed steadily. Cattle breeds vary widely in size; the tallest and heaviest is the Chianina, where a mature bull may be up to 1.8 m (5 ft 11 in) at the shoulder, and may reach 1,280 kg (2,820 lb) in weight. The natural life of domestic cattle is some 25–30 years. Beef cattle go to slaughter at around 18 months, and dairy cows at about five years.

Cattle are ruminants, meaning their digestive system is highly specialized for processing plant material such as grass rich in cellulose, a tough carbohydrate polymer which many animals cannot digest. They do this in symbiosis with micro-organisms – bacteria, fungi, and protozoa – that possess cellulases, enzymes that split cellulose into its constituent sugars. Among the many bacteria that contribute are Fibrobacter succinogenes, Ruminococcus flavefaciens, and Ruminococcus albus. Cellulolytic fungi include several species of Neocallimastix, while the protozoa include the ciliates Eudiplodinium maggie and Ostracodinium album. If the animal's feed changes over time, the composition of this microbiome changes in response.

Cattle have one large stomach with four compartments; the rumen, reticulum, omasum, and abomasum. The rumen is the largest compartment and it harbours the most important parts of the microbiome. The reticulum, the smallest compartment, is known as the "honeycomb". The omasum's main function is to absorb water and nutrients from the digestible feed. The abomasum has a similar function to the human stomach.