The reason why cows keep producing milk is because cows are pregnant, so they will keep producing milk. Mammals generally produce milk during reproductive period, and the purpose of milk production is to provide new food for future generations. On the farm, cows are artificially fertilized to get pregnant and produce milk.

So in advanced dairy factories, cows can't see their children at all, and calves can't see their mothers. They were separated from their mother at birth. Some heifers were fed as cows, repeating her mother's fate; Some calves are sold as beef cattle and so on.

Extended data:

Cow is a kind of cow, and it is an excellent breed that has been highly propagated. Milk produced by cows is nutritious and suitable for long-term drinking, and it is an important raw material for modern dairy industry.

The outline of the bull's head is clear and slightly longer. The neck is thin and wrinkled. Thin skin, short capillaries, less subcutaneous fat, well-proportioned, meticulous and compact, angular. The hindquarters are more developed than the forequarters, with huge breasts and obvious breast veins. Poor heat resistance and high requirements for feeding management.

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