Few people understand how their purchase of milk is connected to the veal industry, when in fact, veal is a by-product of the dairy industry.
For female cows to produce milk, they are kept in a constant cycle of being pregnant and giving birth. While pregnant and shortly thereafter, a cow’s body is producing the hormones necessary to maximize milk production. What happens to all those baby cows? Male calves are useless for milk production and are a different breed of cattle from the ones raised for beef. Dairy cows, female and male, lack the musculature necessary to maximize profits for beef producers. About half of the female calves will become dairy cows, to replace their mothers. The other half of the females are useless to the dairy industry. So, usually on the day they are born, nearly all of the male calves and half of the female calves are taken from their mothers, to be turned into veal.
Calves are typically slaughtered for veal when they are 20-24 weeks old. However, calves are sometimes slaughtered when they are only a few weeks or days old, for "bob veal." "Slink veal" comes from unborn calves and is now banned for human consumption in the United States.
It may seem counterintuitive that milk, which is so connected to birth and life, is also so connected to slaughter and death. However, the animal agriculture industry is not in the business of feeding and housing animals who are not profitable.