In order for a cow to produce milk, she must birth a calf.
Half of the calves are female, and are raised to become milking cows.
The other half?
Consider: It cost $10 to transport a male calf to auction. Each make calf returns $5 to the farmer.
Do not deny their fate, because if you eat pizza or cheese or yogurt or ice cream, that food has been produced to satisfy your taste buds.
I am at a loss for further words.