Livestock can no longer be fed antibiotics "preventatively" or to help them grow bigger. The FDA has ruled to change their regulations of how drugs can be administered to food animals, including those used to make animal feed.
After this ruling, livestock producers can only use antibiotics to treat animals that actually have an infection, and only under the supervision of a veterinarian. These new rules are aimed at decreasing the risk of developing drug-resistant bacteria, sometimes called "super bugs." According to the Centers for Disease Control and Prevention, drug-resistant bacteria cause 2 million illnesses and about 23,000 deaths in the United States each year.
According to an article from The Hill, the Department of Health and Human Services is moving forward with new regulations for hospitals, and President Obama has called on government cafeterias to prioritize meat that has been raised with responsible antibiotic practices.