
Animal productions
In this article we look at three examples of animal products and how they are produced.
Cow milk

To produce milk, a dairy cow must have a calf. The gestation period lasts about 9 months. After birth (calving), the cow will produce milk for about 10 months. She is often inseminated one or two months after calving, so that she produces about one calf per year. After producing milk for 10 months, the cow is dried off (no longer milked), resting for the end of her pregnancy.
Male calves are rarely kept on the farm. Some farmers fatten them, but most of the time they sell them after about ten days for the veal calf industry. On dairy farms, bulls are rarely kept: farmers often prefer artificial insemination, for many reasons: among others, health security, more security for the farmer and animal welfare.
The female calves are all or partly kept on the farm, according to the needs of the breeder for the renewal of his herd. He will most often keep the most promising heifers. The heifers often grow up on the farm, then will have their first calf between two and four years old, depending on the choices of the breeder. They will then join the cow herd.
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Pork meat

To produce pig meat, sows are pregnant for three months, three weeks and three days. A sow usually gives birth twice a year. During gestation, the sows are nowadays housed in groups.
A few days before farrowing, the sows are transferred to maternity rooms, where they are housed in individual pens. The average litter size is 13 to 14 piglets. The piglets are suckled for about one month, until they reach about 8 kg.
At weaning, they are transferred to the "post-weaning" buildings where they stay for about a month and a half, growing from 8 to 30 kg, with a solid diet based on cereals. At the end of the post-weaning period, they are transferred to fattening buildings where they stay for about 3.5 months, increasing from 30 to 120 kg, their slaughter weight.
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The farms can practice only certain phases (birth, post-weaning or fattening) or all the phases (we speak then of "farrow-to-finish")
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Chicken eggs

Contrary to other types of farms where the breeding females are often born on the farm (in cattle for example), the majority of the breeders receive on their farm pullets having grown up in specialized breeders, who will themselves have received the chicks from a specialized hatchery.
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The pullets arrive on the farm at about 18 weeks. The number of eggs laid per hen increases rapidly, reaching a peak when they are 28 weeks old. A hen produces about 250 to 300 eggs for 350 days, after which they are culled (sent to slaughter) before a new group of hens arrives.
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Different ways
to produce
Animal farming is a diverse industry that encompasses different methods of raising animals for various purposes. Two prominent approaches are intensive animal farming and extensive animal farming, but the reality is more nuanced : categorisation of farms is more of a spectrum.