日本鳗鲡爱德华氏菌病病原菌的分离与鉴定

ISOLATION AND IDENTIFICATION OF PATHOGENIC BACTERIA CAUSING EDWARDSIELLOSIS IN EEL ( Anguilla japonica )

从江苏海安和广东中山等地送检的患爱德华氏菌病的日本鳗鲡中分离到１２个菌株，经过对菌株的形态观察，直接荧光抗体法鉴定和生化特性测试，证明了其中１０个菌株为迟缓爱德华氏菌（Ｅｄｗａｒｄｓｉｅｌａｔａｒｄａ）。选用其中４个菌株进行致病力测试结果表明，注射菌液后的日本鳗鲡能出现与自然发病相同的症状，并导致供试日本鳗鲡１００％死亡。对分离菌株进行的药敏试验结果表明，所有菌株均对链霉素、四环素、氯霉素、土霉素和杆菌肽比较敏感，而对红霉素、青霉素Ｇ和先锋霉素Ⅳ不敏感。

The present paper describes the characteristics of pathogenic bacteria of edwardsiellosis in eel ( Anguilla japonica ). The ten strains isolated from the focus of the diseased eels are proved to be the cause of the disease and death of the fish by infection experiment. The symptom caused by the bacteria is similar to the natural symptom. According to the morpholical features indentified by direct fluorescent antibody technique and the biochemical characteristics, the strains WE 2, WE 3, WE 4, WE 5, WE 6, WE 7, WE 8, WE 9, WE 10and WE 12 belong to Edwardsiella tarda . Drug sensitivity tests show that all strains are relatively sensitive to streptomycin, tetracycline, chloramphenicol, oxytetracycline, kanamycin and bacitracin, but less sensitive to erythomycin, pencillin G and cephalexin Ⅳ.