Shedding of foodborne pathogens and microbial carcass contamination of hunted wild ruminants

• Published in: Veterinary microbiology Vol. 159; no. 1-2; pp. 149 - 154
• Main Authors: Obwegeser, Tobias, Stephan, Roger, Hofer, Eveline, Zweifel, Claudio
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 14.09.2012; Elsevier
• Subjects: Abattoirs; animal pathogens; Animals; Animals, Wild; Bacteria - genetics; Bacteria - isolation & purification; Bacterial Load; Bacterial Physiological Phenomena; Bacteriology; Biological and medical sciences; Capra ibex; Capreolus capreolus; Carcass contamination; Cervus elaphus; chamois; compliance; cooling; Enterobacteriaceae; Enterobacteriaceae - genetics; Enterobacteriaceae - isolation & purification; Enterobacteriaceae - physiology; Escherichia coli; evisceration; Fecal shedding; feces; Feces - microbiology; food chain; Food Handling; Food Microbiology; food pathogens; Fundamental and applied biological sciences. Psychology; genes; Genes, Bacterial - genetics; good hygiene practices; humans; Hunted wild ruminants; intimin; Listeria; Listeria monocytogenes; meat carcasses; microbial contamination; Microbiology; Miscellaneous; pathogenicity; Ruminantia; Ruminants - microbiology; Salmonella; shedding; Shiga toxin-producing Escherichia coli; slaughterhouses; verotoxins; Fecal shedding; Listeria monocytogenes; Salmonella; Hunted wild ruminants; Carcass contamination; Shiga toxin-producing Escherichia coli; Escherichia coli; Contamination; Gram positive bacteria; Dissemination; Bacteria; Feces; Veterinary; Shiga like toxin; Enterobacteriaceae
• ISSN: 0378-1135; 1873-2542
• DOI: 10.1016/j.vetmic.2012.03.031

To assess the shedding of selected bacterial foodborne pathogens, fecal samples from 239 hunted wild red deer, roe deer, chamois, and ibex were examined. All samples tested negative for Salmonella spp. and L. monocytogenes, but other Listeria species were occasionally found. Of the 239 fecal samples, 32.6% tested positive for stx (Shiga toxins), 6.7% for eae (intimin) and 13.8% for both stx and eae genes. Among the 56 isolated Shiga toxin-producing Escherichia coli (STEC) strains, 44.6% harbored genes for the Stx2 group, 30.4% for the Stx1 group, and 21.4% for both Stx1 and Stx2. Only two of these strains harbored eae. Hence, wild ruminants constitute a reservoir for STEC, but further characterization data of the isolated strains are required to assess their actual human pathogenicity. In addition, 328 carcasses from hunted wild red deer, roe deer, and chamois were examined for total viable counts (TVC) and Enterobacteriaceae by swabbing. For the examined animal species, average TVC (4.0–4.2logCFUcm−2) and average Enterobacteriaceae counts/detection rates (2.3–2.6logCFUcm−2; 87.5–90%) were at comparable levels. On the other hand, the microbial status of carcasses differed between certain abattoirs by several orders of magnitude. Strict compliance with good hunting and hygiene practices during any step from shooting, through evisceration in the field, to dehiding, cooling, and processing is therefore of central importance to avoid contaminations and to prevent foodborne pathogens carried by the animals from entering the food chain.