Aims: This study was conducted to determine the prevalence of different virulence genes in isolates recovered from poultry, cow, and sheep faeces samples in Behbahan, Khuzestan province, Iran. Methods and results: The presence of cadF, ciaB, racR, cdtA, cdtB, cdtC, and pldA virulence genes among 36 Campylobacter jejuni and 14 Campylobacter coli isolates was detected by polymerase chain reaction. The isolates were screened for the presence of seven virulence genes-namely cadF, racR, ciaB, cdtA, cdtB, cdtC, and pldA-which are responsible for adherence, colonization, invasion, and cytotoxin production in Campylobacter jejuni and Campylobacter coli. The isolates showed wide variation in the presence of these genes. The prevalence of cadF, ciaB, racR, cdtA, cdtB, cdtC, and pldA virulence genes in poultry were 74.36%, 76.92%, 84.61%, 69.23%, 84.62%, 84.62%, and 76.92%, respectively. The prevalence of cadF, ciaB, racR, cdtA, cdtB, cdtC, and pldA virulence genes in cow were 55.56%, 55.56%, 100%, 77.78%, 88.89%, 88.89%, and 88.89%, respectively. The prevalence of cadF, ciaB, racR, cdtA, cdtB, cdtC, and pldA virulence genes in sheep were 0%, 100%, 100%, 0%, 100%, 50%, and 100%, respectively. Conclusions: A high prevalence of ciaB, racR, cdtB, cdtC, and pldA genes was found. Significance and Impact of the Study: The high prevalence of ciaB, racR, cdtB, cdtC, and pldA genes demonstrated that these putative pathogenic determinants are widespread among Campylobacter isolates from poultry, cow, and sheep. The results emphasized that Campylobacter strains in poultry, cow, and sheep have potential pathogenic properties for humans.
