Shoppers don’t have to go far to see the latest food trends.Grocery stores are filled with labels like non-GMO, organic and gluten-free.But the shift toward chicken grown without the use of antibiotics is posing some problems for Delmarva poultry growers.“A 1950s disease came back because we were made to change the way we grow chicken,” said Dan Bautista, a poultry health expert and director of the Lasher Laboratory at the University of Delaware’s Carvel Research & Education Center.“If this was the ’90s, we wouldn’t even be talking about necrotic enteritis,” he said at a June 19 commercial poultry growers workshop in Georgetown.It was the first Delaware-centric poultry workshop put on by University of Maryland Poultry Extension.Bautista said growers working with antibiotic-free birds must now rely on “elbow-grease” and semi-effective feed additives like oregano to combat a deadly disease.“The fact we have a lot of necrotic enteritis is because we haven’t been able to use the tools we have for decades,” he said. “This is a symptom of a social phenomenon.”