DENVER – The Chipotle Mexican Grill chain has adjusted its standards to use some beef treated with antibiotics to ensure this growing business has an adequate supply of beef as US beef supplies continue to tighten, according to the Star Ledger.

Chipotle has traditionally touted its meat as being “naturally raised” and not fattened with antibiotics. Since beef production is predicted to hit a 21-year low next year, about 15 percent to 20 percent of Chipotle’s beef inventory may be treated with antibiotics to prevent illness – but still not to add bulk.

“The change was really rooted in the belief that it’s not the use of antibiotics for the treatment of illness that is the problem,” Chipotle spokesman Chris Arnold recently said in an interview. “The problem is the copious amount of antibiotics that are used to promote growth.”

At present, Chipotle is seeking out new cattle suppliers as well as considering incorporating different cuts of meat for its steak and barbacoa shredded beef burritos. Each year, Chipotle sells approximately 120 million lbs. of naturally raised beef, pork and chicken that meet its antibiotic-free standards. But its continuing growth is making it harder to find suppliers that don’t use antibiotics or hormones to fatten their herds, the article concluded.