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Build your knowledge with top universities and organisations. Learn more about how FutureLearn is transforming access to education. Learn more about this course. Milk production: journey of a calf How could the life cycle of dairy cows be adapted to make dairy farming climate smart? In this article, Dr Marie Dittmann discusses recent research. Share this post. Cows can only produce milk, once they have given birth to a calf.
Dairy cows are inseminated once a year and after a pregnancy of approximately 40 weeks, the cow gives birth to a calf. Want to keep learning? This content is taken from University of Reading online course,. Typically, during the second and third trimesters of pregnancy various hormones, such as progesterone and oestrogen are produced, which stimulate the growth and development of the milk duct system within the udder.
Oxytocin is another important hormone which allows the secretion of the milk to occur - also known as milk 'let down'.
Prolactin a protein levels are stimulated when the udder is suckled by the calf or milked by the milking machine and this needs to occur for milk production to continue.
Cows are usually dried off, or milking is stopped, about two months before their next expected calving to allow the udder time to rest and reset itself for the following lactation. Dairy cows are selectively bred to produce high levels of milk and this is far more than a calf could normally drink.
The volume of milk produced by a cow will depend upon various factors, such as her level of nutrition, breed, genetics and age. For her to continue to produce milk once she has calved, she needs to be milked each day.
Low-producing cows are often the first to be sent to slaughter. Lameness in dairy cows is often attributed to the conditions on factory farms, which see thousands of cows crowded into cramped, indoor spaces. Conditions such as ulcers in their hooves result from standing on concrete for prolonged periods, or a lack of opportunities to exercise. Lameness is also triggered by infections, such as foot rot and digital dermatitis, which occur when cows are forced to stand in feces.
Mastitis is an infection of the mammary gland in mammals caused by a bacterial infection. The condition is one of the most common reasons for reduced production in cows, costing the industry billions of dollars every year. Infections are triggered by unsanitary conditions in barns, where cows lie on soiled bedding, or when they are exposed to contaminated equipment. Mastitis is a painful condition for cows but is only fatal if farmers see production levels drop.
While the natural lifespan of many cows can reach 15 or even 20 years of age, the vast majority of dairy cows are not permitted to live more than years, at which point they're sent to slaughter, usually after their production levels drop. Their death represents an inglorious and unfair end to a life of exploitation. In the US, both dairy cows and beef cattle are processed by the same slaughterhouses. By the time dairy cows arrive, their bodies are often so damaged and diseased that they're unable to make the short walk from the transport truck to the killing floor.
As a result, downed cows are often pushed into slaughterhouses through side doors using bulldozers or other means of prodding. Dairy cows' bodies are so diseased and damaged, many are unable to make the short walk from the transport truck to the killing floor. Cows are then guided into a stall, where they are stunned using a gun with a retractable bullet that is meant to render them unconscious. Unfortunately, this stunning method is often inadequate, leaving cows alive and aware of the subsequent steps of slaughter.
Finally, cows are hung upside down and their throats are slit. To produce milk, the mother cow must give birth to a calf. Female calves can be entered into milking production or sold as veal.
Because male calves are useless to the dairy industry, they are either shot or sent to veal crates. Regardless of sex, calves are taken from their mothers almost immediately after birth. This often causes significant mental distress for the mothers and impairs the social and physical development of the calf. Male calves who will be raised for meat undergo castration. There are several different ways this procedure can be conducted.
Other methods include cutting away portions of the scrotum and destroying testicles by removal or crushing.
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