Antibiotic resistance of Escherichia coli and Salmonella spp isolated from domestic pigeons in Ardabil,Iran

Domestic pigeons are in close contact with humans and other birds in urban areas. As a carrier of Escherichia coli and Salmonella spp, these birds can play a significant role in spreading and transmitting these pathogens to humans and industrial poultry. The aim of this study was to isolate Escherichia coli and Salmonella spp from the cloacal of the domestic pigeons in Ardabil, northwest of Iran and determine their antibiotic resistance. For this purpose, 130 swab samples were prepared from healthy household pigeons in different parts of Ardabil city. After cultivation and isolation of E.coli  and Salmonella spp  in selected media, their colonies were identified by biochemical methods such as EMB, TSI, SIM, MR-VP, indole and urea. Antibiotic resistance of the isolates were determined according to the standard method of disc diffusion. Out of 130 samples, 23 cases (17.69%) of E.coli  and 7 cases (5.38%) of Salmonella spp were isolated. Antibiotic resistance test on E.coli showed that tetracycline and sulfadiazine + trimethoprim had the highest resistance with 86.95% and 82.60%, respectively. While enrofloxacin and gentamicin showed the lowest resistance with 21.73% and 17.39%, respectively. In Salmonella spp  isolates, the highest resistance to tetracycline (100%) and sulfadiazine + trimethoprim (85.71%) and the lowest resistance to co-amoxiclav (14.28%) and florphenicol (14.28%) were observed. All isolates of E.coli  and Salmonella spp were sensitive to ciprofloxacin. The results of the present study indicate the presence of E.coli and Salmonella spp contamination in Ardebil urban pigeons,and also have significant resistance to some antibiotics. The implementation of strict health programs and the principled use of antibiotics in pigeons seem necessary to prevent the transmission of contamination and the spread of antibiotic resistant strains to other poultry and human.