The weight gain product was pulled from the market in 2013 over concerns it caused lameness in cattle
Merck & Co. is taking steps to resume sales of its controversial cattle feed additive Zilmax by changing the way the drug is administered, hoping to recapture some market share in the beef industry, where the U.S. herd has the fewest animals in more than 60 years. The U.S. Food and Drug Administration has approved