The voluntary guidelines it has devised would mean that producers could only use antibiotics to treat and prevent disease in their animals, rather than for the highly controversial practice of promoting growth. The move comes amid concerns that the overuse of antibiotics is creating a new breed of virulent superbug, resistant to many existing drugs, which poses a serious potential threat to human health.
As well as limiting the use of antibiotics, Walmart is also strongly advising its suppliers not to raise its animals in gestation crates or in other conditions deemed to be inhumane. It has also asked its suppliers to reveal their use of antibiotics and treatment of animals.
As Walmart commands more than a 25% share of the US grocery market, it is likely the guidelines will ripple through the entire food supply chain, and prompt rivals to follow in the retailer’s footsteps.
Two years ago the US Food and Drug Administration issued guidelines for drug producers and agricultural companies regarding the voluntary phasing out of antibiotics as growth enhancers in animals.
But Walmart said it was consumer demand that had prompted the move, pointing to an internal survey which revealed that 77% of its consumers would increase their trust and 66% were more likely to shop from a retailer that looked after the treatment of its livestock in a humane fashion.
"Our customers want to know more about how their food is grown and raised, and where it comes from," said Kathleen McLaughlin, senior vice-president for global sustainability at Walmart.
However, the US’ largest poultry producer Sanderson Farms said it planned to continue using antibiotics on its birds, because there were no alternatives for treating a deadly but highly prevalent gut disease.
In March, McDonald’s said that, in two years, its US restaurants would stop buying chicken reared on antibiotics, the first time a major US company has taken such action. Meanwhile, Costco has said it was working with suppliers to phase out livestock routinely dosed with antibiotics intended for human use.