本试验通过对从患病的克氏原螯虾(Procambarus clarkii)肝胰腺中分离得到的一株优势菌X4进行鉴定,旨在确定病因并筛选出敏感药物,为今后克氏原螯虾维氏气单胞菌的防治提供参考.从患病克氏原螯虾肝胰腺分离致病菌,通过对其生理生化特征与16S rRNA基因序列分析进行鉴定,并通过纸片扩散法进行药敏试验.用菌株X4进行人工回归感染试验后,克氏原螯虾发病症状与自然发病症状相似.根据该菌株的形态特征、生化特性、16S rRNA与gyrB基因序列分析结果鉴定为维氏气单胞菌(Aeromonas veronii).该菌株对庆大霉素、多西环素、新霉素及氟苯尼考等15种抗生素敏感,对阿莫西林、克林霉素及苯唑西林3种抗生素耐药.分离得到的菌株X4对克氏原螯虾有致病性,生产中可选用氟苯尼考、新霉素、多西环素等药物进行防治.“,”To determine the cause of death of Procambarus clarkii and screen sensitive drugs, a dominant bacterium X4 was isolated from the hepatopancreas of sick P.clarkii.This study will provide a reference for further prevention and treatment of Aeromomas veronii in P.clarkii.The pathogenic bacterium was isolated and purified from the hepatopancreas of P.clarkii.The identification of phenotypic information of the strain X4 was conducted, which included the biochemical identification and 16S rDNA and gyrB gene sequence determination.Antimicrobial susceptibility test was conducted with disk diffusion technique.The results of the artificial infection test of P.clarkii using X4 displayed that the prevalence of symptoms and spontaneous onset symptoms were the same.According to morphological and biochemical characteristics as well as the result of 16 SrDNA and gyrB gene sequence analyses, the isolated strain X4 was A.veronii.X4 was susceptible to gentamicin, doxycycline, neomycin, florfenicol and other 15 kinds of antibiotics. Meanwhile, it showed resistance to amoxicillin, clindamycinum, oxacillin and other 3 kinds of antibiotics.The isolated bacterial strain X4 was pathogenic to P.clarkii, and prevented by administering drugs such as florfenicol, neomycin and doxycycline in fisheries production.