Background and purpose: Thermophilic Campylobacter spp. are among the most frequently causes of human gastrointestinal infections worldwide which is mainly due to poultry meat consumption. This study aimed at investigating the prevalence and antibiotic resistance of Campylobacter isolates collected from gastrointestinal track of broiler chickens.

Materials and methods: A total of 150 fecal samples were taken from 30 commercial broiler farms during 6 months in 2014. The samples were cultured and incubated in microaerophilic conditions and stained by Carbolfuchsin. The strains were then identified using biochemical tests (catalase and oxidase test). C. jejuni was detected by hippurate hydrolysis test and C. coli and C. lari were identified using indoxyl acetate hydrolysis. Antibiotic resistance against 12 common anti-microbial agents was tested by Kirby-Bauer method.

Results: Thermophilic Campylobacter spp. were isolated in 80% of broiler flocks and 65.3% of the samples. A total of 98 Campylobacter spp. isolates was found in which C. jejuni and C. coli were detected in 79.59% and 20.4%, respectively. The highest levels of resistance were found against nalidixic acid (67%) followed by ciprofloxacin (56%), and tetracycline (56%). The lowest levels of resistance were observed against gentamicin (0%), chloramphenicol (2.5 %), and erythromycin (3%).

Conclusion: Multiple resistance against anti-microbial agents was seen in several isolates and there was no isolate sensitive to all antibiotics.