摘要
为确定引起大鲵患病的细菌病原,采用平板划线法从患病大鲵中分离细菌后,利用革兰氏染色镜检、透射电镜观察及16SrDNA序列分析对分离细菌进行鉴定,然后选择代表株进行人工感染试验以确定其致病性,并利用药敏试验(K-B法)测定9种水产西药和3种水产中药制剂的抑菌效果。综合鉴定结果表明,从患病大鲵中分离出的5株病原菌均为希瓦氏菌(Shewanella xiamenensis),属于革兰氏阴性杆菌;选择的代表株LY3在人工感染大鲵后与自然感染症状一致,确定其为大鲵的致病菌。对患病大鲵进行剖检发现,其组织器官具有明显的病理变化,主要表现为肝脏空泡化降解、脾脏实质弥漫性坏死、肾脏间质性坏死、肾小管裂解以及肺组织纤维化。药敏试验结果显示,代表株LY3对恩诺沙星极度敏感,对氟苯尼考、对磺胺间甲氧嘧啶钠、乳酸诺氟沙星、硫氰酸红霉素高度敏感,对复方磺胺甲噁唑粉等6种药物中度敏感,对盐酸黄连素有耐药性。综上所述,希瓦氏菌引起的同批次大鲵疾病可用恩诺沙星进行治疗。
In order to identify the bacterial pathogen of diseased giant salamander, Andrias davidianus ,the bacteria strains were isolated from diseased Andrias davidianus tissues by streak plate method,followed by identification by gram stain examination,transmission electron microscopic observation and analysis of 16S rDNA sequence.Strain LY3 was chosen to test the pathogenicity by artificial infection experiment and the susceptibility to 9 western and 3 traditional Chinese drugs of aquaculture was tested by K-B analysis.All five isolates were proved to be Shewanella xiamenensis ,which was gram-negative rod bacterium.The symptoms of artificially infected Andrias davidianus were consistent with the results of natural infection,which suggested that strain LY3 was the pathogenic bacterium.Histological changes were observed in Andrias davidianus ,such as vacuolar degeneration of hepatocytes in the liver,diffuse necrosis of the splenic parenchyma,interstitial necrosis and tubular collapse in the kidney,and fibration in the lung.The results of drug sensitivity test showed that strain LY3 was extremely sensitive to enrofloxacin and highly sensitive to florfenicol,sulfamonomethoxine sodium,norfloxacin lactat and erythromycin thiocyanate,and moderately sensitive to 6 drugs including compound sulfamethoxazole power,but was resistant to berberine.Taken together, Andrias davidianus disease caused by Shewanella xiamenensis can be treated with enrofloxacin.
作者
牛树辉
陈梦飞
吕帅飞
李声平
杨红飞
高小蝉
NIU Shuhui;CHEN Mengfei;LU Shuaifei;LI Shengping;YANG Hongfei;GAO Xiaochan(College of Animal Science and Technology,Henan University of Science and Technology,Luoyang 471023,China)
出处
《河南农业科学》
北大核心
2019年第8期147-153,共7页
Journal of Henan Agricultural Sciences
基金
河南省科技攻关项目(182102110402)
河南科技大学博士科研启动基金项目(13480079)
河南科技大学大学生研究训练计划(SRTP)项目(2018369)
关键词
大鲵
希瓦氏菌
16SrDNA
病理组织学观察
药敏试验
Andrias davidianus
Shewanella xiamenensis
16S rDNA
Pathohistological observation
Drug sensitivity test
