五倍子对鳗鲡4株常见病原菌的体外抗菌后效应

Postantibiotic effect of Galla Chinensis on pathogenic bacteria of eels in vitro

关键词:  五倍子  鳗鲡  病原菌  抗菌后效应

Key words:  Galla Chinensis  eels  pathogenic bacteria  postantibiotic effect (PAE)

摘要:

采用试管液体二倍稀释法测定中药五倍子对鳗鲡养殖中常见主要致病菌(肠杆菌B01、迟缓爱德华氏菌B09、豚鼠气单胞菌B18和嗜水气单胞菌B27)的最小抑菌浓度(MIC)。然后再采用菌落计数法分别测定五倍子在0.25、0.5、1、2、4 倍于各菌MIC时对鳗鲡病原菌株B01、B09、B18、 B27的体外抗菌后效应(PAE)。结果显示：五倍子在0.25、0.5、1、2、4倍MIC值时对鳗鲡病原菌株B01、B09、B18、B27均具有一定的体外抗菌后效应，且PAE与药液浓度在一定范围内(0.25～4倍MIC)呈剂量依赖性，当药液浓度达4倍MIC时，PAE明显延长( P < 0.05)；五倍子对各病原菌株B01、B09、B18、B27的PAE值在1倍MIC浓度以上差异显著( P < 0.05)，在4倍MIC时对于病原菌株B01和B18的PAE之间差异较小。结论：实验结果提示在养殖鳗鲡病害防治中设计投药方案时, 对主要致病菌B01、B09、B18和B27感染所造成的烂鳃、肝胆肿大、败血症等疾病, 除了考虑药代动力学和MIC指标外，还应考虑PAE因素，可适当延长给药间隔时间，降低药物对鳗鲡的副作用及对其摄食量和生长的负面影响。

Abstract:

The postantibiotic effect (PAE) of Galla Chinensis on cardinal pathogenic bacteria of eels including of Enterobacter B01, Edwardsiella tarda B09, Aeromonas caviae B18, Aeromonas hydrophila B27, in vitro were determined in this study. Dilution method was used for the drug of Galla Chinensis removal and Mueller-Hinton agar colony counting method was used to monitored the growth of bacteria. The results showed that marked PAE was found even in the subinhibitory concentration (sub-MIC) when Galla Chinensis were used against four common pathogenic bacteria of eels and the isolate obtained from veterinary clinic at concentration of0.25, 0.5 , 1 , 2 , 4譓IC. The duration of PAE was enhanced with the increasing concentration, showing strongly a concentration dependent, especially at 4譓IC , the PAE was obvirously prolonged (P < 0.05). It suggested that longer dosing interval should be recommended when the Galla Chinensis drug used against eels pathogenic bacteria, which achieved reducing side-effect against eels and reversely working on growth of eels.