Isolation and characterization of Clostridium difficile in farm animals from slaughterhouse to retail stage in Isfahan, Iran.

To determine the prevalence of Clostridium difficile in farm animals from slaughterhouse through to retail stage, a total of 750 samples of feces, posteviscerated and washed carcass were collected from cattle, camels, goats, and sheep in Isfahan, Iran. The overall prevalence of C. difficile in feces, posteviscerated and washed carcass were 20 (13.3%), 23 (15.3%), and 11 (7.3%), respectively; while C. difficile was isolated from 79 (26.3%) retail samples. Twenty-nine (3.8%) isolates were toxigenic, with most toxigenic isolates (n = 17, 5.6%) identified from the retail stage. All toxigenic isolates harbored tcdA and tcdB; however, all were negative for cdtB. The 29 isolates were classified into 21 different ribotypes. This study revealed evidence of existence of toxigenic C. difficile in farm animal feces and meat in Iran.