Research Note: Characterization of antibiotic resistant phenotypes and linked genes of Escherichia coli and Klebsiella pneumoniae from healthy broiler chickens, Karnataka, India

The study was carried out to estimate the burden and pattern of antibiotic resistance and to identify antibiotic resistance genes with focus on ESBL producers, plasmid mediated quinolone resistance, and tetracycline efflux genes, in faecal bacterial isolates collected from poultry farms of coastal Southern Karnataka, India. High resistance to fluoroquinolones was observed with 94% Escherichia coli and 80% Klebsiella pneumoniae being resistant to both ciprofloxacin and levofloxacin. All the Escherichia coli strains were resistant to tetracycline (100%). qnrB (38%) was the most common gene detected followed by qnrS (27%) and qnrA (21.5%). All Klebsiella pneumoniae isolates resistant to tetracycline harbored tetA gene. Most of the isolates in our study had high MAR indices indicating rampant use of antibiotics.