in the u.s what is the most common use for antibiotics
Antibiotic use in livestock Eighty percent of antibiotics sold in the United States are used on livestock. The majority of these antibiotics are given to animals that are otherwise healthy. Rather, it is normal practice to mix antibiotics with fodder to promote healthier living conditions and to encourage animal growth.[36] The use of antibiotics in animals is to a large degree involved in the emergence of antibiotic-resistant microorganisms.[37] Antibiotics are used in food with the intention of not only preventing, controlling, and treating diseases, but also to promote growth.[38] Antibiotic use in animals can be classified into therapeutic, prophylactic, metaphylactic, and growth promotion uses of antibiotics.[39] All four patterns select for bacterial resistance, since antibiotic resistance is a natural evolutionary process, but the non-therapeutic uses expose larger number of animals, and therefore of bacteria, for more extended periods, and at lower doses. They therefore greatly increase the cross-section for the evolution of resistance.