Purpose: The objective of this study was to evaluate the presence of C. difficile in raw meats and farm samples including soil, feathers, and animal feces.
Methods: Samples from chicken meat (n = 77), turkey meat (n = 62), pork meat (n = 52), feces (n = 36), feathers (n = 36), and soil (n= 36) were collected and analyzed for C. difficile. Test samples were prepared and plated on medium Cycloserine-Cefoxitin-Fructose Agar (CCFA) and Blood Agar plates. All plates were subjected to anaerobic conditions at 37°C for 48h. Colonies were further tested for Indole and L-Proline aminopeptidase production by using C.diff PRO™ kit. To confirm C. difficile isolates, DNA was isolated using the phenol-chloroform method. C. difficile was confirmed using the polymerase chain reaction amplification of the toxin A and B genes (tcdA and tcdB).
Results: Presumptive colonies showed a yellowish-green appearance when viewed under UV light with a characteristic cresol odor. Some of the colonies tested positive for Indole and L-Proline aminopeptidase production. The prevalence of C. difficile in pork, chicken, and turkey was 6.8%, 4.2%, and 3.7%, respectively. Presence of C. difficile was also indicated in farm samples feces (13%), feathers 2.8%, and soils 5.5%.
Significance: The results of this study suggest that the prevalence of C. difficile in the U.S. retail meats and farm environment is low. Nevertheless, the presence of C. difficile in retail meat indicates its potential as an emerging foodborne pathogen.