Pet food regulation forum raises spectrum of issues

Transcript and recording posted; agency taking comments through Oct. 25

October 1, 2021 (published)
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With around two-thirds of American households having pets, according to the U.S. Food and Drug Administration's Center for Veterinary Medicine, pet food safety is a topic of high interest.

The possibility that ferrets could be developing urinary stones from certain diets and that dogs may be accumulating toxic levels of copper added to commercial foods were among a spectrum of subjects raised in a listening session hosted last week by the U.S. Food and Drug Administration.

The Sept. 24 virtual meeting, meant to be a sounding board for stakeholders, including veterinarians, drew a capacity audience of 1,000 registrants.

Other issues raised by a dozen speakers included the prospect of allowing hemp derivatives in animal feed; a concern that the FDA's attention has waned on diet-associated dilated cardiomyopathy in dogs; and questions about the role of the private, nonprofit Association of American Feed Control Officials in influencing the regulation of pet food.

Individuals and organizations may still express their thoughts on pet food oversight to the agency, which is accepting comments through Oct. 25. A recording and a transcript of the session are posted online.

Among those who spoke at the event were two veterinarians, whose concerns centered on suspected harms linked to certain pet food ingredients.

Dr. Cheryl Greenacre, an exotic animal practitioner at the University of Tennessee College of Veterinary Medicine, said that in the past five to 10 years, she has seen an increasing and "alarming number" of cystine stones in the urinary tracts of ferrets, requiring surgery to remove. She and other researchers suspect the stones are related to pea and lentil proteins in grain-free diets fed to ferrets.

In brief

Greenacre recommended not allowing pea and lentil proteins in ferret foods and adding a warning to cat foods containing those ingredients that they should not be given to ferrets. She said most of the cases she sees involve ferrets fed diets formulated for other animals.

Dr. Sharon Center, an internal medicine specialist at Cornell University College of Veterinary Medicine, raised a concern that commercial dog foods contain excessive amounts of copper. She traces the issue to a 1993 modification in food-grade copper in premix supplements used in dog foods. Center described the problem as insidious, happening quietly to some dogs that are consistently fed commercial foods. Center said the condition, in which copper accumulates in the liver, is difficult to diagnose in time to treat effectively because affected dogs show no signs of illness early on.

Long-term, copper accumulation can cause fatal injury to the liver, Center said.

In addition to the veterinarians, a member of a group concerned about diet-associated dilated cardiomyopathy in dogs, comprised of veterinarians, others in pet professions and pet owners, criticized what she called "the delegitimization of the DCM issue."

Catherine Castonguay, representing the Diet-Associated DCM Education Alliance, said pet food manufacturers whose products have been implicated in cases of DCM have sounded "a repeated theme" that there is no evidence of harm from their formulations, while not acknowledging that in many cases, dogs given a different diet recover from what can be a lethal heart disease.

Castonguay said the misleading messages are "further empowered by silence from the FDA on this issue." Noting that her group continues to learn about new cases of DCM in dogs, she called on the FDA to provide updates every six to 12 months and make its case-reporting portal easier to use.

During remarks at the start of the session, Dr. Steven Solomon, director of the FDA Center for Veterinary Medicine (CVM), said receiving input from the public "helps us build a bigger picture of the various perspectives of FDA pet food oversight." Among the agency's "top ongoing concerns," he said, are bacterial contaminants, toxins, and excessive or insufficient amounts of vitamins or other essential nutrients.

He added: "The review of ingredients themselves continues to be a priority for the center. Congress recently gave CVM some additional resources to increase our staffing levels. With additional staff members, we've reduced the time it takes to complete our ingredient review, and we hope to continue that trend into the future."

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