(NEWSER) – Farmers have been loading up their animals with antibiotics for years now in order to help them grow beefy and profitable, a practice that public health advocates have long complained about. (Think "superbugs" and the rise of antibiotic-resistant infections in humans, for example.) Today, the FDA took its first action to curb the practice, reports USA Today. It is asking drug companies to voluntarily change their labels to make it illegal for farmers to use the drugs solely to boost growth. Already, two of the biggest such companies, Zoetis and Elanco, say they will comply. Also, farmers will now need a veterinarian's permission to administer the drugs.