Investigation ofListeria,Salmonella, and ToxigenicEscherichia coliin Various Pet Foods

Abstract

The 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, conducted a study to evaluate the prevalence of selected microbial organisms in various types of pet foods. The goal of this blinded study was to help the Center for Veterinary Medicine prioritize potential future pet foodtesting 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 1056 samples over 2 years. Laboratories tested for Salmonella, Listeria, Escherichia coli O157:H7 enterohemorrhagic E. coli, and Shiga toxin-producing strains of E. coli (STEC). Dry and semimoist dog and cat foods purchased from local stores were tested during Phase 1. Raw dog and cat foods, exotic animal feed, and jerky-type treats purchased through the Internet were tested in Phase 2. Of the 480 dry and semimoist samples, only 2 tested positive: 1 for Salmonella and 1 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 positive for Salmonella. These pathogens were isolated from raw foods and jerky-type treats, not the exotic animal dry feeds. This 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.

Evaluation of microbial contamination and effects of storage in raw meat‐based dog foods purchased online

“…Listeria monocytogenes was previously found in 16% and 54% of the RMBDs evaluated by Nemser and colleagues (Nemser et al, ) and by Van Bree and colleagues (van Bree et al, ) respectively; in the same studies, 17% and 43% of the samples confirmed to be positive also for other Listeria species. In the present investigation, the prevalence of these bacteria was higher as L. monocytogenes and other Listeria species were found in 65% and 55% of the analysed products.…”

Multilaboratory Survey To Evaluate Salmonella Prevalence in Diarrheic and Nondiarrheic Dogs and Cats in the United States between 2012 and 2014

“…There are, however, ample studies showing that raw diets still culture positive in surveys of dog food products (68–70) or when linked to outbreaks (43, 71). Dog treats have also tested positive in past surveys (72; https://www.fda.gov/AnimalVeterinary/ResourcesforYou/AnimalHealthLiteracy/ucm278271.htm); however, treat consumption did not show any evidence of a significant statistical association with the Salmonella status in our study.…”

Assessment of Listeria monocytogenes in pet food

“…In Malaysia, there is no data regarding the contamination of dog or cat food diets with any type of microorganism. Studies conducted by Nemser et al [18] and US Food and Drug Administration [5] are one of the few studies that reported the contamination of commercially prepared dog and cat food diets by L. monocytogenes. However, the contaminated dog and cat food diets were found to be commercially prepared raw foods.…”

“…However, there are chances that these pet food diets may have been contaminated by other pathogens such as Salmonella and Escherichia coli [18]. As a result, it is essential for the pet owners to be careful when handling pet food.…”