Study: Highest Pathogen Levels on Raw Pet Foods, Jerky Treats

The U.S. Food and Drug Administration’s Veterinary Laboratory Investigation and Response Network (Vet-LIRN), in collaboration with the Food Emergency Response Network (FERN) and its Microbiology Cooperative Agreement Program (MCAP) laboratories, has conducted a study to evaluate the prevalence of selected microbial organisms in various types of pet foods.

 

The goal of this blinded study, published in the September issue of Foodborne Pathogens and Disease, was to help the Center for Veterinary Medicine prioritize potential future pet food testing efforts.The study also increased the FERN laboratories’ screening capabilities for foodborne pathogens in animal feed matrices since such pathogens may also be a significant health risk to consumers who come into contact with pet foods.

 

Six U.S. Food and Drug Administration FERN MCAP laboratories analyzed approximately 1,056 samples over two years. Laboratories tested for Salmonella, Listeria, E. coli O157:H7, and Shiga toxin-producing strains of E. coli (STEC).

 

Dry and semi-moist dog and cat foods purchased from local stores were tested during Phase 1 (October 2010 to September 2011). Canned and wet pet foods were not collected as part of this project. Raw dog and cat foods, exotic animal feed, and jerky-type treats purchased through the Internet were tested in Phase 2 (October 2011 to July 2012).

 

Raw foods were usually frozen and consisted of ground meat or sausage-type tubes of products made from animals such as rabbits and cows. It is unknown how long frozen samples had been frozen prior to shipping. Dry foods excluded cat and dog foods, but included hamster, gerbil, rabbit, amphibian, or bird food and pellets. Jerky-type treats included chicken jerky products, pig ears, and bully stick types of products. All samples were tested within four months of receipt. Overall, 576 samples were analyzed in Phase 2.

 

The study was not a regulatory surveillance program, and the manufacture information was blinded, researchers noted. Of the 480 dry and semi-moist samples, only two tested positive: one for Salmonella and one for Listeria greyii. However, of the 576 samples analyzed during Phase 2, 66 samples were positive for Listeria (32 of those were Listeria monocytogenes) and 15 samples tested positive for Salmonella. These pathogens were isolated from raw foods and jerky-type treats, not the exotic animal dry feeds. This was the first report of Listeria monocytogenes contamination of commercial pet foods.

 

The study showed that raw pet foods may harbor food safety pathogens such as Listeria monocytogenes and Salmonella. Consumers should handle these products carefully, being mindful of the potential risks to human and animal health. FDA has been investigating pet jerky treats since 2007 due to thousands of reported pet illnesses and deaths that may be related to their consumption. According to the agency, these reports involve more than 5,600 dogs, 24 cats, three humans and more than 1,000 canine deaths.

 

While FDA has tested the pet jerky treats for many contaminants and continues to investigate the problem, it has not been able to pinpoint the cause of the illnesses.