동물유래 생식품, 사료 및 분변중 listeria monocytogenes의 분포와 분리균의 특성에 관한 연구 3. 분리균의 약제감수성 및 plasmid progile

Characteristics of Isolates and Incidence of Listeria monocytogenes in Faeces from Animals, in Feed and in Raw Foods of Animal Origin 3. Antimicrobial Susceptibilities and Plasmid Profile of L. Monocytogenes

This study was conducted to investigate the antimicrobial susceptibilites and plasmid DNA of L. monocytogenes isolates. Peak distributions of minimum inhibitory concentration (MIC) of the isolates were 0.78㎍/ml for ampicillin and penicillin, 3.13㎍/ml for cephalothin, 6.25㎍/ml for amikacin, and all the isolates were 1.56㎍/ml for vancomycin. Most of 42 isolates were sensitive to ampicillin and penicillin, but isolates were resistant to cephalexin (100%), tetracycline (71.4%), erythromycin (64.3%) and neomycin (50%). Multiple resistance patterns were observed in 64.3% of the resistant strains. The most common resistance patterns were CpxEmTc (28.5%) and CPxEmNmTc (26.2% ). A total of 42 isolates of L. monocytogenes were subjected to the test for the presence of plasmid DNA and 9 strains (14.3%) had single plasmid element. The plasmids recovered from these organisms had molecular weight from 54 or 58 Kb.