Determination of antibiotic residues in the animal tissues by agar diffusion technique

Abstract

After oxytetracyline (20 mg/kg) and tetracycline (50 mg/ kg) were given orally to the broiler chickens, antibiotic residues in tissues were determined by agar diffusion technique. Bacillus cereus (ATCC 11778) was used as a sensitive strain. Petri dishes punched at 8 mm in diameter were incubated at 37°C overnight. A total of 124 tissues was tested. The oxytetracycline and tetracycline residues that have been found in tissues were respectively 0.32 - 2.56 µg/gr and 0.080 - 0.240 µg/gr. The limites of the test strain sensitivity were determined 0.04 µg and 0.01 µg levels for oxytetracycline and tetracycline respectively.