Occurrence of antimicrobial-resistant bacteria from client-owned pets and their raw meat-based diets Advocates of raw?meat diets claim various health benefits for dogs, and while none of the purported benefits have been validated, owners of raw meat?fed animals stand by their convictions (1-4). In contrast, a 2-year study conducted by the US Food and Drug Administration found that raw pet food is more likely than other types of pet food to carry bacteria, including Salmonella and Listeria monocytogenes (5). The FDA issued a public health warning about the risks of raw pet food diets and both the American Animal Hospital Association and the American Veterinary Medical Association officially recommend against feeding raw meat-based diets to dogs. Numerous studies have validated the concerns associated with raw food diets (RFD), but none has determined the prevalence of drug resistant bacteria (6-8). To address this question, fecal specimens will be collected from animals fed a RFD. Samples will also be collected from animals on a commercial diet, but also receiving antibiotics and others considered antibiotic nave. The survey focus will be on multidrug resistant bacteria including vancomycin-resistant enterococci (VRE), carbapenemase-producing bacteria and colistin resistant Enterobacteriaceae, but random enteric isolates will be selected for testing for antimicrobial resistance. Fecal samples will be submitted in Cary-Blair medium and inoculated onto imipenem containing MacConkey agar to select for carbapenem-resistant bacteria. Lucie Bardet- Jean Marc Rolain media will be utilized to select for colistin-resistant bacteria and VRE (9). Conventional biochemical testing including the Vitek 2 Gram-positive and Gram- negative ID cards (BioMerieux) will be utilized for bacterial identifications (10). Antimicrobial susceptibility profiles will be determined by micro broth dilution (Sensititre automated system; Trek Diagnostics, Westlake, OH, USA) and will include antimicrobials utilized in the National Antimicrobial Monitoring System. Isolates that are ESBL positive will undergo multiplex qPCR for the extended spectrum beta lactamases blaTEM, blaSHV, blaCTX-M and blaCMY-2 and sequencing to determine the variant (11, 12). Multiplex qPCR platforms will be utilized to examine for plasmid mediated colistin resistance genes: mcr-1 to-mcr-9 and tet (M), tet (L), cat, cmlA which confer resistance to the tetracyclines and phenicols (13, 14).
The goal of this study is to examine feces of pets and raw pet food (RPF) to determine if consuming RPF will increase the risk of foodborne illness and spreading bacteria resistant to vancomycin, carbapenem or colistin in pets.
