Tyson Foods will drop the "No Antibiotics Ever" label from some of its chicken products by the end of the year, according to media reports.
The Wall Street Journal, which first reported the news, said Tyson will remove the label from certain fresh, frozen, and ready-made chicken products because it is reintroducing ionophores to some of its chickens' diets. Ionophores are antibiotics that are mainly used to control coccidiosis, an intestinal parasitic disease common in poultry, but the World Health Organization and the US Food and Drug Administration (FDA) do not consider them to be important for human medicine.
Tyson is the largest US chicken producer. In 2017, the company announced it was eliminating the use of all antibiotics in fresh and frozen chicken products bearing the company name. It was one of several chicken producers and fast-food companies to make the move to antibiotic-free chicken, which has helped significantly reduce the use of medically important antibiotics in poultry production.
New labels aim to clarify use of non-medically important antibiotics
Public health and veterinary consultant Gail Hansen, DVM, MPH, explained that Tyson is likely making the move because they can't use the "No Antibiotics Ever" label on chicken products in which ionophores have been used, and tracking and relabeling those products "can be a headache." In practice, she added, it means the company will be using ionophores in more of its birds to minimize the effects of coccidiosis.
"Tyson has not found a suitable substitute or management practice for ionophores to control the coccidia protozoal parasite," she told CIDRAP News.
The company told Reuters that it plans to change the labeling on its chicken products to clarify that its chickens are not given medically important antibiotics. Antibiotic stewardship advocates argue that the widespread use of medically important antibiotics in food-animal production contributes to the emergence and spread of antimicrobial resistance and is a threat to human health.
"Based on current science, Tyson branded products are transitioning to No Antibiotics Important to Human Medicine (NAIHM) which is expected to be complete by the end of the calendar year," a Tyson Foods spokesperson said.
Hansen said that while she has "historically been adamant" that ionophores weren't likely to be linked to antibiotic resistance, a recent pilot study conducted by researchers with Wageningen University in the Netherlands has made her rethink that view.
In the study, researchers conducted whole-genome sequencing on 20 Enterococcus faecium and Enterococcus faecalis isolates from poultry and analyzed them for the presence of resistance genes. They found that the presence of resistance genes for the ionophore salinomycin was correlated with the presence of resistance genes for erythromycin, tetracycline, and ampicillin, which are designated as medically important antibiotics.
"This is an alarming observation, since it implies that the use of ionophores may drive the transfer and dissemination of other, clinically relevant types of antimicrobial resistance by co-selection," the study authors wrote. "These results question the sustainability of the prophylactic use of ionophores in broiler production."
According to the most recent FDA sales report, ionophores accounted for 82% of all non-medically important antibiotics sold for use in food-producing animals in the United States in 2021, and 19% of all non-medically important antibiotics sold for food-producing animals are used in chickens.
"It is true that there are no ionophores used in human medicine (and not likely to be)," Hansen said. "But the article from Wageningen University is certainly worth watching and considering."
