Detection of Antibiotic Residues in Dressed Chicken from Commercial

Using the Four Plate Test (FPT), 64.2% (104/162) of liver samples from freshly dressed chickens at dressing plants of commercial chicken producers and backyard raisers were detected to contain antibiotic residues. Chickens from backyard raisers had a significantly higher proportion of positives (p < 0.05) at 80.8% (63/78), as compared to 48.8% (41/84) of commercial producers, indicating more frequent indiscriminate use of antibacterials in backyard poultry operations, either through improper dosing or non-observance of the appropriate withdrawal period. On the frequency of detection of suspect type of antimicrobials in chickens as inferred by the FPT, penicillin type ranked highest in occurrence for chickens of both backyard and commercial producers, followed by aminoglycosides. The least frequent type of antibiotic detected for both producers was the macrolides. The number of chickens, positive for penicillin, tetracycline, sulfonamide, and aminoglycoside types of antibiotics,was significantly higher (p <0.05) for backyard raisers than for commercial producers. Results are relevant as they indicated that antibiotics may be improperly used by producers, and that there is a strong need for heightened surveillance through regular mandatory testing of chickens sold for human consumption. Key words: antibiotic residues, backyard raisers, commercial producers, dressed chicken, Four Plate test