Researchers at Iowa State University received a $1 million grant from the U.S. Department of Agriculture’s National Institute of Food and Agriculture to study how manure management systems in livestock production affect the development of bacteria capable of resisting antibiotics, ISU announced this week. The majority of antibiotics used today are in animal production; the researchers aim to identify what resistant genes are proliferating in bacteria, and how widely those bacteria spread and persist in soil. The team will study manure samples from Iowa pig farms in the research.