Cattle graze in a field near Sacramento, Calif. California Gov. Jerry Brown, along with many health advocacy groups, has called the overuse of antibiotics "an urgent public health problem."
Chipotle restaurant workers fill orders for customers. The company is now sourcing some of its pork from a British supplier that uses antibiotics to treat pigs when ill. Gail Hansen, a veterinarian and longtime critic of antibiotic overuse on farms, welcomes this shift in Chipotle's stance on the drugs.
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