<P> In order for the cows to reach high performance in milk yields and reproduction, they must be in great condition and comfortable in the system of which they are reared . Once an individual's welfare is reduced, so does her efficiency and production . This creates more cost and time on the operation, therefore most farmers strive to create a healthy, hygienic, atmosphere for their cattle . As well as provide quality nutrition that will keep the cows yield high . </P> <P> The practice of dairy production in a factory farm environment has been criticized by animal rights activists . Some of the ethical reasons regarding dairy production cited include how often the dairy cattle are impregnated, the separation of calves from their mothers, and the fact that the cows are considered "spent" and culled at a relatively young age, as well as environmental concerns regarding dairy production . </P> <P> The production of milk requires that the cow be in lactation, which is a result of the cow having given birth to a calf . The cycle of insemination, pregnancy, parturition, and lactation is followed by a "dry" period of about two months before calving, which allows udder tissue to regenerate . A dry period that falls outside this time frames can result in decreased milk production in subsequent lactation . Dairy operations therefore include both the production of milk and the production of calves . Bull calves are either castrated and raised as steers for beef production or veal . </P> <P> Animal rights groups such as Mercy for Animals also raise welfare concerns by citing undercover footage showing abusive practices at factory farms . </P>

When does a cow begin to give milk
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