Journal of Pure and Applied MicrobiologyVol. 9 No. 1

Antibiotic Resistance Pattern and Phylogenetic Analysis of Commensal Escherichia coli Isolated from Poultry

Ram Hari Meena1, Irfan Ahmad Mir1, Sunil Maherchandani1, Kanchan Jangir1, Nishtha Purohit1 and S.K. Kashyap1

1Department of Veterinary Microbiology and Biotechnology, College of Veterinary and Animal Science, Rajasthan University of Veterinary and Animal Science, Bikaner - 334001, India.

Received on 10 January 2015 and accepted on 06 Feburary 2015



In the present investigation a total of 40 isolates of Escherichia coli from healthy poultry birds were investigated for antibiotic resistance pattern and distribution of various phylogroups in different age groups of birds. All the isolates showed green metallic sheen on Eosin Methylene Blue agar plate and were confirmed by various biochemical test. Genotypic confirmation by 16S rRNA gene revealed an amplicon of 662bp in all Escherichia coli isolates. The antibiogram pattern showed high distribution of resistance to multiple drugs among all the isolates with at least each isolate being resistant to three or more antibiotics. The antibiogram results showed that 100% of the isolates were resistant to penicillin, oxacillin and nalidixic acid. Resistance level was more than 50% for doxycycline (97.5), tetracycline (90%), erythromycin (85%), rifampicin (80%) and trimethoprim (75%). The study revealed that amikacin and levofloxacin were the most effective drugs. Out of the four main phylogenetic groups (A, B1, B2, and D), only two phylogroups viz A and B1 were obtained by multiplex PCR with a prevalence of 62.5% and 37.5% respectively.

Keywords : Escherichia coli, poultry, PCR, Phylogroup, Antibiotic resistance.