Identification and quantification of antimicrobial activity in commercially available chicken meat in a large urban centre in Pakistan

Large-scale use and misuse of antibacterial agents for infection prevention and growth promotion in chicken has grown alongside mass production of poultry as a primary protein source in human diet. This has led to concern about promotion of antibiotic resistance among bacteria of clinical significance to human disease. The objectives of this study are to identify which, if any, antimicrobials are commonly found in commercially available broiler chicken and determining the minimum amount of meat with enough microbial inhibitory activity that can be measured in routine culture. Four test organisms, namely ATCC 25922, ATCC 51299, clinical isolate MRSA and clinical isolate E. coli were used. The antimicrobial sensitivity profiles of the test organisms were determined against beta-lactams, tetracyclines, aminoglycosides, sulphonamides, fluoroquinolones and phenicols. 8 mm tissue pieces of liver, muscle and kidney samples were obtained and plated on all four plates of our test organisms. The zones of inhibition, if any, around the tissue samples determined the presence of antimicrobial residues in meat. 270 tissue samples of liver, muscle and kidney were tested for the presence of antimicrobial residues. In total 90 freshly butchered broiler chicken samples were collected, each contributing a liver, kidney and a muscle tissue sample. The samples were collected randomly from butcher shops across geographical bins of the city of Lahore. The results showed that 73.3% of the samples were positive for antimicrobial activity. Of these 69.6% of the samples were positive for the presence of sulfonamides, 9.3% had flurphenicol, 7.0% had quinolone activity, 6.7% had aminoglycoside activity and 3.7% had tetracyclines in them.