【摘要】 从全身弥漫性出血合并腹水的养殖大菱鲆Scophthalmus maximus的腹水、肝脏和肾脏中分离到3株菌落形态相同的优势菌,编号为L-49231、L-59231、L-59232。选用L-49231菌,通过注射、浸泡和灌喂3种途径分别对两种规格(全长(12±2)cm,体重(30±2)g;全长(18±2)cm,体重(125±5)g)的养殖大菱鲆进行人工感染试验,结果证实:此菌可经上述3种途径造成该病的发生,注射和浸泡方式的感染率均为100%,死亡率分别为100%和66.7%;灌喂方式未见死亡,感染率为85.7%。该菌经革兰氏染色为阴性,杆状,大小为2~3μm×1~1.2μm,周生鞭毛,兼性厌氧,接触酶为阳性,氧化酶为阴性,V.P试验为阴性。根据《常见细菌系统鉴定手册》所描述的爱德华氏菌属的生理生化特性,菌株L-49231为迟钝爱德华氏菌Edwardsiella tarda。更多还原

【Abstract】 Three strains of bacteria(L-49231,L-59231 and L-59232) with same shape of colony were isolated from ascites,hepatopancrease and kidney in cultured hemorrhagic turbot(Scophthalmus maximus).The infected experiments including injection,bath and oral administration for turbot(body length(12±2)cm and(18±2)cm; total weight(30±2)g and(125±5) g) confirmed that L-49231 was the pathogen of the disease and infected the fish by three pathways mentioned above.The injection and bath resulted in fish death at a mortality of 100% and 66.7%,respectively.But oral administration had an infection rate of 85.7% and did not cause death.This bacterium is gram negative,rod in shape,1 μm in width,2-3 μm in length,peritrichous flagella,motile,and catalase positive.V.P.test showed that the bacterium have nitrate reduction negative,oxydase negative,and anaerobes.The characteristics of L-49231 is consistent with Edwardsiella tarda.更多还原