Antibiotic residue monitoring in laboratory animal serum by microbial inhibition test

Objective To develop a detection method for antibiotic residues in laboratory animal serum,and to ensure the accuracy of the results of the microbiological quality monitoring.Methods Antibiotic residues in 1640 serum samples of laboratory animals were tested by microbial inhibition assay of Bacillus stearothermophilus,and the results were compared with that of the antibiotic detection kit Premi@Test.Results Antibiotic residues were positive in sera of mice,rats,guinea pigs,rabbits and dogs,with a positive rate of 27.2%,16.4%,39.9%,23.7% and 47.6%,respectively.The results were consistent with that obtained with Premi@test(X2 =16.680,P0.05).Serum antibiotic residues and DHL agar colony growth had certain correlation(X2 =9.939,P0.05).Conclusions The microbial inhibition method of Bacillus stearothermophilus used as an indicator is not only capable of detecting antibiotic residues in animal sera,low cost,and simple operation,but also has a good sensitivity and repeatability.This study provides a basis for detection of antibiotic residues in the laboratory animals,and makes up for the blank in the quality testing of laboratory animals.