Purpose: The aim of the current study was to estimate the prevalence of ESBL-producing Escherichia coli in feed, feces, and soil from poultry houses and farm compound. In addition, E. coli was evaluated for resistance to antimicrobial drugs.
Methods: A total of 150 samples of feed, feces, and soil were collected for analysis. Biochemical identification of the isolates was performed using oxidase and API 20E test methods. Escherichia coli isolates, identified at 98% confidence level, were screened for ESBLs by plating on ChromID ESBL agar plates. Cefotaxime (30 μg) and ceftazidime discs (30 μg), with or without clavulanate (10 μg), were used to confirm ESBL-producing E. coli. The antimicrobial susceptibility was determined using the Bauer and Kirby disk diffusion technique. ESBL-producing isolates were also analyzed for the presence of blaTEM, blaSHV and blaCTX-M genes by PCR.
Results: ESBL-producing E. coli isolates were detected in 4.3%, 15.2%, and 80.5% in feed, soil, and poultry feces, respectively. About two-third of the isolates were found to be susceptible to all the antimicrobials used in this study; 31.6% (36/114) of the isolates were resistant to one or more of the antimicrobials tested. Multidrug resistance to three or more antimicrobials was observed in 21.9% (n=25) of the E. coli. Escherichia coli isolates were resistant to critically important human antibiotics, like erythromycin (99.1%; n=113), tetracycline (84. 2%; n= 96), amikacin (14.9%; n=12), and ciprofloxacin (3.5%; n=4). The blaCTX-M, blaSHV, and blaTEM β-lactamase genes were also detected in ESBL-producing E. coli.
Significance: This study provides evidence that poultry farms could possibly be a potential source for ESBL-producing Escherichia coli.