Feeding animals can be costly, and is frequently the most expensive aspect of animal agriculture. Farmers feed byproducts from other businesses to lower the amount of hay and grain fed to their animals in order to keep costs low and their animals healthy. Animals require vitamins and minerals in addition to protein and energy. Farmers can purchase vitamin and mineral blends to boost an animal's regular feed. Vitamins and minerals can also be fed in the form of a solid block, which the animals will lick while grazing. Farmers will also use medication in animal feed to cure or prevent disease.
Farmers cautiously check and document when they feed pharmaceuticals to livestock for market since animals must be taken off medications weeks in advance.