养殖河蟹弧菌病病原茵分离鉴定及其胞外产物的致病性

从杭州一养蟹场的病蟹体内分离到3株细菌,经形态学检查、生化性质测定,鉴定为副溶血弧菌。人工感染健康蟹,48h内均发生死亡,死亡率100％,证实副溶血弧菌为河蟹的致病菌。药敏试验结果表明,此病原菌对链霉素、利福平、卡那霉素、复方新诺明、环丙沙星、氟哌酸、四环素、氯霉素、氟嗪酸、复达欣、菌必治、萘啶酸等药物高度敏感。分离菌株培养物经理化方法处理获得的胞外产物蛋白具有明胶酶、几丁质酶、淀粉酶、酪蛋白酶、脂酶、磷脂酶等多种酶活性及溶血活性,并对河蟹具有明显的致病作用。

Identification of Vibrio parahemolyticus isolated from cultured Eriocheir sinensis and pathogenicity of its extracellular products

Three strains of bacteria were isolated from the diseased Eriocheir sinensis , which were cultured in the ponds in Hangzhou. Morphological, physiological and biochemical characteristics of these isolates were the same as those of Vibrio parahenwlyticus, therefore, these pathogens isolated from the diseased E. sinensis were identified as Vibrio parahenwlyticus. The mortality of artificial infection was 100% , which ascertained that the bacterial isolates were the pathogens of the E. sinensis. The pathogens were highly sensitive to streptomycin, rifampin, kanamycin, SMZ + TMP, ciprofloxacin, norfloxacin, tetracycline, chloramphenicol, ofloxacin, ceftazidime, ceftriaxone, nalidixic acid. The suspension was centrifuged, precipitated by (NH4)SO4, dialysed, concentrated and filter sterilized, and the extracellular products obtained were found to show gelatinase, chitinase, amylase, caseinase, lipase, phospholipase activities, and to be highly toxic to E. sinensis .