This article is about the dairy industry in general. For dairy farming specifically, see dairy farming.
A dairy farm near Oxford, New York in the United States.
A dairy is a facility for the extraction and processing of animal milk—mostly from goats or cows, but also from buffalo, sheep, horses or camels —for human consumption. Typically it is a farm (dairy farm) or section of a farm that is concerned with the production of milk, butter and cheese.
Terminology differs slightly between countries. In particular, in the U.S. a dairy can also be a facility that processes, distributes and sells dairy products, or a room, building or establishment where milk is kept and butter or cheese is made. In New Zealand English a dairy means a corner convenience store, or Superette—and dairy factory is the term for what is elsewhere called a dairy.
As an attributive, the word dairy refers to milk-based products, derivatives and processes, and the animals and workers involved in their production: for example dairy cattle, dairy goat. A dairy farm produces milk and a dairy factory processes it into a variety of dairy products. These establishments constitute the dairy industry, a component of the food industry.
History
Milk-producing animals have been domesticated for thousands of years. Initially they were part of the subsistence farming that nomads engaged in. As the community moved about the country so did their animals accompany them. Protecting and feeding the animals were a big part of the symbiotic relationship between the animal and the herder.
In the more recent past, people in agricultural societies owned dairy animals that they milked for domestic or local (village) consumption, a typical example of a cottage industry. The animals might serve multiple purposes (for example, as a draught animal for pulling a plough as a youngster and at the end of its useful life as meat). In this case the animals were normally milked by hand and the herd size was quite small so that all of the animals could be milked in less than an hour—about 10 per milker. These tasks were performed by a dairymaid (dairywoman) or dairyman. The word dairy harkens back to Middle English dayerie, deyerie, from deye (female servant or dairymaid) and further back to Old English dæge (kneader of bread).
With industrialisation and urbanisation the supply of milk became a commercial industry with specialised breeds of cow being developed for dairy, as distinct from beef or draught animals. Initially more people were employed as milkers but it soon turned to mechanisation with machines designed to do the milking.
Farmer milking a cow by hand.
Historically, the milking and the processing took place close together in space and time: on a dairy farm. People milked the animals by hand; on farms where only small numbers are kept hand-milking may still be practiced. Hand-milking is accomplished by grasping the teats (often pronounced tit or tits) in the hand and expressing milk either by squeezing the fingers progressively, from the udder end to the tip, or by squeezing the teat between thumb and index finger then moving the hand downward from udder towards the end of the teat. The action of the hand or fingers is designed to close off the milk duct at the udder (upper) end and, by the movement of the fingers, close the duct progressively to the tip to express the trapped milk. Each half or quarter of the udder is emptied one milk-duct capacity at a time.
The stripping action is repeated, using both hands for speed. Both methods result in the milk that was trapped in the milk duct being squirted out the end into a bucket that is supported between the knees (or rests on the ground) of the milker, who usually sits on a low stool.
Traditionally the cow, or cows, would stand in the field or paddock while being milked. Young stock, heifers, would have to be trained to remain still to be milked. In many countries the cows were tethered to a post and milked. The problem with this method is that it relies on quiet, tractable beasts, because the hind end of the cow is not restrained.
In 1937 it was found that bovine somatotropin (bST or rBST) (bovine growth hormone) would increase the yield of milk. Monsanto developed a synthetic version of this hormone. In February 1994 bST was approved by the Food and Drug Administration (FDA) for use in the U.S. It has become common, in the U.S. but not elsewhere, to inject it into milch kine (dairy cows) in order to increase their production by up to 15%.
However, there are claims that this practice can have negative consequences for the animals themselves. A European Union scientific commission was asked to report on the incidence of mastitis and other disorders in dairy cows and on other aspects of the welfare of dairy cows. The commission's statement, subsequently adopted by the European Union, stated that the use of rBST substantially increased health problems with cows, including foot problems, mastitis and injection site reactions, impinged on the welfare of the animals and caused reproductive disorders. The report concluded that on the basis of the health and welfare of the animals, rBST should not be used. Health Canada prohibited the sale of rBST in 1999; the recommendations of external committees were that despite not finding a significant health risk to humans, the drug presented a threat to animal health and for this reason could not be sold in Canada.
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