Detection of Cytolethal distending toxin (cdt) Genes in Escherichia coli Isolates from Poultry Colibacillosis

Detection of Cytolethal distending toxin (cdt) genes in Escherichia coli isolates from poultry colibacillosis has been reported from variety of pathogenic Gram negative bacteria such as Escherichia coli, Escherichia albertii, Campylobacter spp and Shigella spp. CDT producing Escherichia coli (CTEC) has been isolated from patients with gastrointestinal, urinary tract infection and sepsis. Up to now the source of human infection remains unknown. Since meat and meat products have been incriminated as the predominant causes of many food borne infections and poultry meat is one of the most important sources of animal proteins in Iran, the purpose of this study was detection of Cytolethal distending toxin gene in Escherichia coli isolated from poultry colibacillosis. 246 Escherichia coli isolated from avian colibacillosis (APEC) and fifty-four fecal E.coli isolates from the feces of apparently healthy birds (AFEC) were investigated for the presence of cdt genes. Isolates collected from veterinary medicine laboratories in Tehran and detection carried out with colony hybridization assay. The results showed only 1.62% of isolates possess cdt gene. This finding indicates that poultry meat probably could not be the main reservoir of CTEC. However expression of CDT from other Gram negative bacteria in poultry meat is not unexpected.