A New Screening Method for the Detection of Antibiotic Residues in Meat and Poultry Tissues.

A simplified procedure is described for screening meat and poultry tissues for the presence of antibiotic residues. The method involved inserting a cotton swab directly into meat or poultry tissues, allowing it to absorb tissue fluids. The swab is then removed and placed on a test plate using Antibiotic Medium No.5 (BBL) and a seed layer of Bacillus subtilis ATCC 6633 spores. The plate is incubated overnight at 29 C, then observed for evidence of inhibition around the swab. The method was compared with the conventional bioassay procedures using routing meat and poultry tissues submitted for analysis. Of a total 1,780 tissues tested, the screening procedure was either in agreement with or detected inhibition was not found by the conventional procedures in 99.4% of the samples. The test was shown to have equal sensitivity to conventional procedures for detection of chlortetracycline, oxytetracycline, tetracycline, erythromycin, neomycin, penicillin, streptomycin and tylosin.