| Foodborne illness is an escalating concern upon public health. The prevalence of Yersinia enterocolitica was investigated in swine fecal, retail chitterlings, and raw cow's milk from North Carolina. Forty-five swine fecal samples, and forty unpasteurized cow milk samples supplied by the North Carolina A&T State University farm were evaluated for the presence of Y. enterocolitica. Thirty, uncleaned chitterling samples procured from a local grocery store were also studied. Isolates identified as presumptive positive were characterized as colonies with a pink or deep-red center on MacConkey and CIN agar, and verified further through polymerase chain reaction (PCR) testing for the 16S rRNA gene for the Yersinia genera. Out of the forty-five swine fecal samples tested, 2 (4.4%) of the samples were presumptive positive for Y. enterocolitica. Forty dairy cattle samples were tested for Y. enterocolitica, of which 3 (7.5%) of the samples were presumptive positive by the plating method on selective agars. Of the 30 chitterling samples evaluated by PCR for the 16S rRNA gene, 8 (26%) samples contained the identification gene for the bacteria of interest. There was a total of 13 (11.3%) samples that were categorized as positive for Yersinia. In comparison amongst sample types, the chitterlings showed the highest prevalence for Y. enterocolitica. After conducting virulence tests, the fecal samples were revealed as non-pathogenic. Only one of the milk samples were considered pathogenic and consisted of the following virulent genes: Yersinia heat-stable toxin (yst), invasin (inv), attachment invasion locus (ail), virulence regulon transcriptional activator (virF), Yersinia adehesin A ( yadA), and the O:3 antigen gene (rfbC). Seven of the eight (87.5%) chitterling samples were shown to be pathogenic. Disc diffusion was conducted to determine the antimicrobial susceptibility of the isolates. Over half (55.5%) of the antimicrobial agents were found effective, with isolates being completely susceptible to ciprofloxacin, kanamycin, trimethoprim, cefotaxime, and gentamycin. Ampicillin was determined to be least effective, where 84.6% of the samples presented resistance to the drug. Random amplified polymorphic DNA (RAPD) analysis and enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) were used to evaluate genetic similarity among the Yersinia isolates. There was approximately 85% similarity between two chitterlings and a fecal isolate during RAPD testing. With ERIC-PCR the largest similarity among all samples was at 95%, which was found between isolates from a chitterling and milk sample.;Cross contamination at the farm site could be the root cause of this pathogen being prevalent in farm animal and food sources, which does pose a risk to public human health when food is improperly prepared. Keywords: Yersinia enterocolitica, polymerase chain reaction, antibiotic testing, chitterlings. |
