This July 9 file photo shows Craig Rowles, of Elite Pork Partnership, standing with hogs in one of his confinement buildings in Carroll, Iowa. Rowles gives his pigs virginiamycin, which he says has been used for decades and is not absorbed by the gut of the pig. He withdraws the drug three weeks before his hogs are sent for slaughter. He also monitors his pigs for signs of drug resistance to ensure they are getting the most effective doses.
Read the article: Pressure up to stop antibiotics in agriculture