黄颡鱼源嗜水气单胞菌对盐酸沙拉沙星耐药性获得与消失速率的测定

Acquisition and vanishing rate of drug resistance of Aeromonas hydrophila in Pelteobagrus fulvidraco against sarafloxacin hydrochloride

【目的】测定黄颡鱼源嗜水气单胞菌对盐酸沙拉沙星的耐药性,为制定盐酸沙拉沙星在水产动物疾病防治中的用药程序提供参考依据。【方法】采用二倍稀释法测定最小抑菌浓度(MIC),以传代法测定菌株的耐药性获得和消失速率。【结果】盐酸沙拉沙星对WZAh-01、WZAh-02、WZAh-03和YFAh-04菌株的MIC分别为0.625、0.3125、0.3125和0.15625μg/mL;在含有盐酸沙拉沙星的培养基中连续传代8次后,4株供试菌株的MIC上升了64～512倍;将获得的强耐药性诱变菌株于4℃中保存30 d,结果发现WZAh-02、WZAh-03和YFAh-04菌株的MIC下降了50%,WZAh-01菌株的MIC保持不变。【结论】黄颡鱼源嗜水气单胞菌经连续8代的耐药性诱导后对盐酸沙拉沙星获得很强的耐药性,且产生耐药突变后的菌株具有相当稳定的遗传性,耐药性在短期内很难消除,因此在实际生产上不宜常用或滥用盐酸沙拉沙星。

[Objective ]Drug resistance of Aeromonas hydrophila in Peheobagrus fulvidraco against Saratloxacin hy- drochloride was determined to provide references for setting drug-use procedure of Saratloxacin hydrochlo^de in aquatic animal disease treatment. [Method]Minimal inhibitory concentration（MIC） was detected using double dilution method. Ac- quisition and vanishing rate of drug resistance were detected using passaging method. [Resuh]MIC of WZAh-01 ,WZAh-02, WZAh-03 and YFAh-04 against Saratloxacin hydrochlode was 0.625,0.3125,0.3125 and 0.15625 p^g/mL. After eight se- rial passages in Saratloxacin hydrochloride media, MIC of four strains rose by 64-512 times. The obtained mutant strains with strong drug resistance were kept at 4~C for 30 days. It was found that MIC of WZAh-02, WZAh-03 and YFAh-04 dropped by 50%, while MIC of WZAh-01 remained the same. [Conclusion]Aeromonas hydrophila in Peheobagrus ful- vidraeo under eight serial passages had strong drug resistance against Sarafloxacin hydrochloride. The obtained mutant strains maintained stable heredity. Sarafloxacin hydrochloride should not be overused in production because drug-resis- tance could not be eliminated in a short time.