McDonald's declined comment on sales figures and its plans for beef.
More than 70 percent of medically important antibiotics in the United States are sold for livestock use. Scientists have warned routine use of antibiotics to promote growth and prevent illness in healthy farms animals contributes to the rise of dangerous antibiotic-resistant superbug infections, which kill at least 23,000 Americans each year and pose a significant threat to global health.
"If fully implemented, (the plans) could be a total game changer that could transform the marketplace given the company's massive buying power," Jean Halloran, Consumers Union's director of food policy initiatives, said in a statement.
This article was provided by Reuters.