Animal husbandry is the branch of agriculture concerned with that are raised for meat, animal fiber, milk, or other products. It includes day-to-day care, management, production, nutrition, selective breeding, and the raising of livestock. Husbandry has a long history, starting with the Neolithic Revolution when animals were first Domestication, from around 13,000 BC onwards, predating farming of the first crops. During the period of ancient societies like ancient Egypt, cattle, sheep, , and were being raised on farms.
Major changes took place in the Columbian exchange, when Old World livestock were brought to the New World, and then in the British Agricultural Revolution of the 18th century, when livestock breeds like the English Longhorn cattle and Lincoln Longwool sheep were rapidly improved by agriculturalists, such as Robert Bakewell, to yield more meat, milk, and wool. A wide range of other species, such as horse, water buffalo, llama, rabbit, and guinea pig, are used as livestock in some parts of the world. Insect farming, as well as aquaculture of fish, , and , is widespread. Modern animal husbandry relies on production systems adapted to the type of land available. Subsistence farming is being superseded by intensive animal farming in the more developed parts of the world, where, for example, beef cattle are kept in high-density feedlots, and thousands of may be raised in broiler houses or battery farm. On poorer soil, such as in uplands, animals are often kept more extensively and may be allowed to roam widely, foraging for themselves. Animal agriculture at modern scale drives climate change, ocean acidification, and biodiversity loss.
Most livestock are , except (among the most commonly-kept species) for pigs and chickens which are . Ruminantia like cattle and sheep are adapted to feed on grass; they can forage outdoors or may be fed entirely or in part on rations richer in energy and protein, such as pelleted cereals. Pigs and poultry cannot digest the cellulose in forage and require other high-protein foods.
In southern Asia, the elephant was domesticated by 6,000 BC.Gupta, Anil K. in Origin of agriculture and domestication of plants and animals linked to early Holocene climate amelioration, Current Science, Vol. 87, No. 1, 10 July 2004 59. Indian Academy of Sciences. Fossilised chicken bones dated to 5040 BC have been found in northeastern China, far from where their wild ancestors lived in the jungles of tropical Asia, but archaeologists believe that the original purpose of domestication was for the sport of Cockfight. Meanwhile, in South America, the llama and the alpaca had been domesticated, probably before 3,000 BC, as beasts of burden and for their wool. Neither was strong enough to pull a plough which limited the development of agriculture in the New World. Horses occur naturally on the steppes of Central Asia and their domestication began around 3,000 BC in the Black Sea and Caspian Sea region. Although horses were originally seen as a source of meat, their use as and for riding followed. Around the same time, the wild ass was being tamed in Egypt. were domesticated soon after this, with the Bactrian camel in Mongolia and the Arabian camel becoming beasts of burden. By 1000 BC, caravans of Arabian camels were linking India with Mesopotamia and the Mediterranean.
The semi-natural, unfertilised pastures formed by traditional agricultural methods in Europe were managed by grazing and mowing. As the ecological impact of this land management strategy is similar to the impact of such natural disturbances as grazing and wildfire, this agricultural system shares many beneficial characteristics with a natural habitat, including the promotion of biodiversity. This strategy is declining in Europe today due to the intensification of agriculture. The mechanized and chemical methods used are causing biodiversity to decline.
Animals can be kept extensively or intensively. Extensive systems involve animals roaming at will, or under the supervision of a herdsman, often for their protection from Predation. in the Western United States involves large herds of cattle grazing widely over public and private lands. Similar cattle stations are found in South America, Australia and other places with large areas of land and low rainfall. Ranching systems have been used for sheep, deer, ostrich, emu, llama and alpaca.
In the uplands of the United Kingdom, sheep are turned out on the fells in spring and graze the abundant mountain grasses untended, being brought to lower altitudes late in the year, with supplementary feeding being provided in winter. In rural locations, and poultry can obtain much of their nutrition from scavenging, and in African communities, hens may live for months without being fed, and still produce one or two eggs a week.
At the other extreme, in the more developed parts of the world, animals are often intensively managed; dairy cows may be kept in zero-grazing conditions with all their forage brought to them; beef cattle may be kept in high density ; pigs may be housed in climate-controlled buildings and never go outdoors; poultry may be reared in barns and kept in cages as laying birds under lighting-controlled conditions. In between these two extremes are semi-intensive, often family-run farms where livestock graze outside for much of the year, silage or hay is made to cover the times of year when the grass stops growing, and fertiliser, feed, and other inputs are brought onto the farm from outside.
In many climates grass growth is seasonal, for example in the temperate summer or tropical rainy season, so some areas of the crop are set aside to be cut and preserved, either as hay (dried grass), or as silage (fermented grass). Other forage crops are also grown and many of these, as well as crop residues, can be ensiled to fill the gap in the nutritional needs of livestock in the lean season.
Extensively reared animals may subsist entirely on forage, but more intensively kept livestock will require energy and protein-rich foods in addition. Energy is mainly derived from cereals and cereal by-products, fats and oils and sugar-rich foods, while protein may come from fish or meat meal, milk products, legumes and other plant foods, often the by-products of vegetable oil extraction.
Pigs and poultry are non-ruminants and unable to digest the cellulose in grass and other forages, so they are fed entirely on cereals and other high-energy foodstuffs. The ingredients for the animals' rations can be grown on the farm or can be bought, in the form of pelleted or cubed, compound foodstuffs specially formulated for the different classes of livestock, their growth stages and their specific nutritional requirements. Vitamins and minerals are added to balance the diet. Farmed fish are usually fed pelleted food.
Selective breeding has been responsible for large increases in productivity. For example, in 2007, a typical broiler chicken at eight weeks old was 4.8 times as heavy as a bird of similar age in 1957, while in the thirty years to 2007, the average milk yield of a dairy cow in the United States nearly doubled.
Where the condition is serious, governments impose regulations on import and export, on the movement of stock, quarantine restrictions and the reporting of suspected cases. are available against certain diseases, and antibiotics are widely used where appropriate. At one time, antibiotics were routinely added to certain compound foodstuffs to promote growth, but this practice is now frowned on in many countries because of the risk that it may lead to antimicrobial resistance in livestock and in humans.
Governments are concerned with Zoonosis, diseases that humans may acquire from animals. Wild animal populations may harbour diseases that can affect domestic animals which may acquire them as a result of insufficient biosecurity. An outbreak of Nipah virus in Malaysia in 1999 was traced back to pigs becoming ill after contact with fruit-eating , their faeces and urine. The pigs in turn passed the infection to humans. Avian flu H5N1 is present in wild bird populations and can be carried large distances by migrating birds. This virus is easily transmissible to domestic poultry, and to humans living in close proximity with them. Other infectious diseases affecting wild animals, farm animals and humans include rabies, leptospirosis, brucellosis, tuberculosis and trichinosis.
All these animals have been domesticated over the centuries, being bred for such desirable characteristics as fecundity, productivity, docility and the ability to thrive under the prevailing conditions. Whereas in the past cattle had multiple functions, modern dairy cow breeding has resulted in specialised Holstein Friesian-type animals that produce large quantities of milk economically. Artificial insemination is widely available to allow farmers to select for the particular traits that suit their circumstances.
Whereas in the past cows were kept in small herds on , grazing pastures and being fed hay in winter, nowadays there is a trend towards larger herds, more intensive systems, the feeding of silage and "zero grazing", a system where grass is cut and brought to the cow, which is housed year-round.
In many communities, milk production is only part of the purpose of keeping an animal which may also be used as a beast of burden or to draw a plough, or for the production of fibre, meat and leather, with the Cow dung being used for fuel or for the improvement of soil fertility. Sheep and goats may be favoured for dairy production in climates and conditions that do not suit dairy cows.
In the developed world, the majority of the poultry reared for meat is raised indoors in big sheds, with automated equipment under environmentally controlled conditions. Chickens raised in this way are known as broilers, and genetic improvements have meant that they can be grown to slaughter weight within six or seven weeks of hatching. Newly hatched chicks are restricted to a small area and given supplementary heating. Litter on the floor absorbs the droppings and the area occupied is expanded as they grow. Feed and water is supplied automatically and the lighting is controlled. The birds may be harvested on several occasions or the whole shed may be cleared at one time.
A similar rearing system is usually used for turkeys, which are less hardy than chickens, but they take longer to grow and are often moved on to separate fattening units to finish.Sherwin, C.M. (2010). "Turkeys: Behavior, Management and Well-Being". In The Encyclopaedia of Animal Science. Wilson G. Pond and Alan W. Bell (Eds). Marcel Dekker. pp. 847–49 Ducks are particularly popular in Asia and Australia and can be killed at seven weeks under commercial conditions.
Fish hatchery provide larval and juvenile fish, crustaceans and shellfish, for use in aquaculture systems. When large enough these are transferred to growing-on tanks and sold to fish farms to reach harvest size. Some species that are commonly raised in hatcheries include , , salmon, tilapia, and . Similar facilities can be used to raise species with conservation needs to be released into the wild, or game fish for restocking waterways. Important aspects of husbandry at these early stages include selection of breeding stock, control of water quality and nutrition. In the wild, there is a massive amount of mortality at the nursery stage; farmers seek to minimise this while at the same time maximising growth rates.
Sericulture, the rearing of silkworms, was first adopted by the Chinese during the Shang dynasty. The only species farmed commercially is the domesticated Bombyx mori. When it spins its cocoon, each larva produces an exceedingly long, slender thread of silk. The larvae feed on Morus alba and in Europe, only one generation is normally raised each year as this is a deciduous tree. In China, Korea and Japan however, two generations are normal, and in the tropics, multiple generations are expected. Most production of silk occurs in the Far East, with a synthetic diet being used to rear the silkworms in Japan.
Insects form part of the human diet in many cultures. In Thailand, crickets are farmed for this purpose in the north of the country, and palm weevil larvae in the south. The crickets are kept in pens, boxes or drawers and fed on commercial pelleted poultry food, while the palm weevil larvae live on cabbage palm and sago palm trees, which limits their production to areas where these trees grow.
Farm animals are widespread in books and songs for children; the reality of animal husbandry is often distorted, softened, or idealized, giving children an almost entirely fictitious account of farm life. The books often depict happy animals free to roam in attractive countryside, a picture completely at odds with the realities of the impersonal, mechanized activities involved in modern intensive farming.
Pigs, for example, appear in several of Beatrix Potter's "little books", as Piglet in A.A. Milne's Winnie the Pooh stories, and somewhat more darkly (with a hint of animals going to slaughter) as Babe in Dick King-Smith's The Sheep-Pig, and as Wilbur in E. B. White's Charlotte's Web. Pigs tend to be "bearers of cheerfulness, good humour and innocence". Many of these books are completely Anthropomorphism, dressing farm animals in clothes and having them walk on two legs, live in houses, and perform human activities. The children's song "Old MacDonald Had a Farm" describes a farmer named MacDonald and the various animals he keeps, celebrating the noises they each make.
Many urban children experience animal husbandry for the first time at a petting farm; in Britain, some five million people a year visit a farm of some kind. This presents some risk of infection, especially if children handle animals and then fail to hygiene; a strain of E. coli infection 93 people who had visited a British interactive farm in an outbreak in 2009. Historic farms such as those in the United States offer farmstays and "a carefully curated version of farming to those willing to pay for it", sometimes giving visitors a romanticised image of a pastoral idyll from an unspecified time in the pre-industrial past.
Ancient civilisations
Medieval husbandry
Columbian exchange
Agricultural Revolution
Practices
Systems
Feeding
Breeding
Animal health
Range of species
Products
Branches
Dairy
Meat
Poultry
Aquaculture
Insects
Effects
Environmental impact
Animal welfare
In culture
See also
Notes
Citations
Sources
External links
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