【摘要】 2021年上海市一家鳜鱼养殖场暴发出血病，初始典型症状为下颌出血。本研究通过细菌分离、分子鉴定、生化反应以及健康鳜鱼感染试验等，确认鳜鱼发病死亡由维氏气单胞菌（Aeromonas veronii）和迟缓爱德华氏菌（Edwardsiella tarda）共同感染所致。分离的维氏气单胞菌鸟氨酸脱羧酶（ODC）和赖氨酸脱羧酶（LDC）反应均为阴性，表明其既不属于维氏气单胞菌维氏生物群（A. veronii biogroup veronii），也不属于维氏气单胞菌温和生物群（A. veronii biogroup sobria），但在遗传上与温和生物群更近；迟缓爱德华氏菌生化反应不产生H₂S。分离菌腹腔注射感染健康鳜鱼幼鱼后，被感染幼鱼均出现了死亡现象，且相同数量级病原回感鳜鱼，维氏气单胞菌感染后，鳜鱼发病更快，死亡率更高，感染量为1×10⁷ cfu/尾时即可导致鳜鱼幼鱼在24 h内100%死亡。两种病菌都对硫酸新霉素和红霉素耐药，而对氟苯尼考都高度敏感。本研究为养殖鳜鱼出血病的治疗和控制提供了参考。更多还原

【Abstract】 In 2021,an outbreak of hemorrhagic disease occurred in a mandarin fish farm in Shanghai City,with mandibular hemorrhage as the initial typical symptom. The disease was confirmed to be caused by co-infection with Aeromonas veronii and Edwardsiella tarda as verified by bacterial isolation,molecular identification,biochemical reaction and infection test for healthy mandarin fish. Both ornithine decarboxylase（ODC）and lysine decarboxylase（LDC）reactions of the isolated Aeromonas veronii were negative,indicating it neither belonged to A. Veronii biogroup veronii,nor to A. veronii biogroup sobria,but was genetically closer to the mild biogroup;no H₂S was produced by the biochemical reaction of Edwardsiella tarda. After healthy young mandarin fish was intraperitoneally injected by the isolated bacteria,all the infected fish died. When the fish were infected by pathogens with same order of magnitude,it was found that they were attacked faster with higher mortality rate after infection with Aeromonas veronii,and 100%fish would die within 24 hours when the amount of infection reached 1×10⁷ cfu/tail. Both the bacteria were resistant to neomycin sulfate and erythromycin,but highly sensitive to flufenicol. A reference was therefore provided for future treatment and control of hemorrhagic disease in cultured mandarin fish.更多还原