Molecular detection and characterization of Escherichia coli, Salmonella spp. and Campylobacter spp. isolated from broiler meat in Jamalpur, Tangail, Netrokona and Kishoreganj districts of Bangladesh

The study was conducted to isolate, identify and characterize bacterial samples from broiler meat collected from 20 different upazilla markets of Jamalpur, Tangail, Netrokona and Kishoreganj districts of Bangladesh. A total of 20 samples were subjected to bacteriological isolation and identification, and the isolated bacteria were subjected to antimicrobial susceptibility testing using disc diffusion method. Among the samples, 75% (n=15) were contaminated with Campylobacter spp., 70% (n=14) were with Salmonella species and 85% (n=17) were contaminated with Escherichia coli. The Campylobacter spp., Salmonella spp. and E. coli were isolated and identified by culturing on Blood agar, Xylose-Lysine Deoxycholate (XLD) agar, and MacConky and eosin methylene blue (EMB) agar respectively. Isolates of Campylobacter spp., Salmonella spp. and E. coli were biochemically analyzed. Campylobacter specific 16S rRNA genes were amplified from the isolates. Campylobacter spp. and E. coli isolates were positive to 16S rRNA gene based polymerase chain reaction (PCR). Almost all isolates of Campylobacter spp., Salmonella spp. and E. coli showed highest susceptibility to ciprofloxacin, norfloxacin and gentamicin. However, most isolates were resistant to amoxicillin and erythromycin. Some isolates showed susceptibility to tetracycline, streptomycin and azithromycin. The findings of this study revealed that there is presence of multidrug resistant isolates of Campylobacter spp., Salmonella spp. and E. coli in broiler meat. Results of this research project demonstrated the high level of microbial contamination and occurrence of pathogenic bacteria in broiler meat sold in markets of Bangladesh.   Key words: Broiler meat, Escherichia coli, Salmonella, Campylobacter, molecular detection, characterization.