【作者】 刘堂水；

【导师】 陈昌福； 樊海平；

【作者基本信息】 华中农业大学 ， 水产养殖， 2007， 硕士

【摘要】 本论文共分三部分，第一部分是对尼罗罗非鱼养殖主要细菌性疾病进行全面调查，通过2005-2006近两年的调查，发现了养殖尼罗罗非鱼常见的15种细菌性疾病，针对各种疾病阐述了其流行病学病原菌的流行情况、危害程度以及控制方法，以期为生产实践和科研作参考。第二部分介绍了作者对尼罗罗非鱼“突眼”病病原体的分离鉴定及其防治对策的研究。2006年5月上旬至10月上旬，福建省漳州市和广东省广州市人工养殖的尼罗罗非鱼陆续发病，主要症状为病鱼食欲不振，生长缓慢，反应迟钝，离群独游，眼球突出，浑浊发白，有的单突，有的双突，严重的眼球脱落，少数伴有严重的烂鳃，所解剖病鱼，有不同程度腹水、肾组织糜烂淤血，肝脏有淡黄色斑块，触之易碎。胆囊肿大为正常的2-4倍，呈墨绿色，肠道透明，内有黄色液体，食物残渣少，鳃盖、鳍及肌肉等部位充血、出血，肝脏呈暗褐色。首先，从福建省漳州市人工养殖的尼罗罗非鱼分离到3个菌株，经注射和浸泡法人工感染试验，证明其中3菌株能够导致供试尼罗罗非鱼100％的死亡。根据对菌株的形态、生理生化特性和API细菌鉴定系统结果，TE60829NA，TL60910NA和TL60914NA证实为病原菌—痢疾志贺氏杆菌(Shigella dysenteria)。其主要特征为革兰氏阴性，不具动力的短杆菌，通过纸片法，测定抑菌圈直径大小可以粗略的筛选出效果相对明显的药物，结果表明所分离到的病原菌对氨苄青霉素、羧苄西林、红霉素、多西环素、氟哌酸、卡那霉素敏感，对呋喃唑酮、复方新诺明、磺胺和庆大霉素不敏感。然后在试管内测定了5种效果明显的抗菌药物对尼罗罗非鱼“突眼”病致病菌的抑、杀菌作用。将氨苄青霉素按4.0μg／g鱼体重的用药量拌和在饲料中，投喂患病的尼罗罗非鱼，在用药后的第二天，死亡率大幅度下降，连续用药三天后，即停止了死亡。证明了氨苄青霉素对尼罗罗非鱼“突眼”病有很好的疗效；最后将痢疾志贺氏杆菌制备成福尔马林灭活菌苗F-SD(Formalin killed S. dysenteria, F-SD)、苯酚灭活菌苗P-SD(Phenol killed S. dysenteria, P-SD)、热灭活菌苗H-SD(Heat killed S. dysentria, H-SD)分别接种注射昆明鼠后，通过测定受免昆明鼠血清中的凝集抗体效价，对不同方法进行了比较，用不同方法制备的3种菌苗注射接种昆明鼠后第31 d后，经受免疫的昆明鼠血清中凝集抗体效价均有不同程度的上升，其中以F-SD免疫组最高，P-SD免疫组次之，凝集抗体效价最低的为H-SD免疫组，而对照组中血清中的凝集抗体效价都很低。第三部分论文报道了从湖北省宜都市和长阳土家族自治县内清江河内养殖网箱中患病斑点叉尾鲴体内和体表分离致病菌的初步鉴定结果。从患病斑点叉尾鲴上共分离19个菌株，经分别采用注射和浸泡法人工感染试验，证明其中11个菌株能导致试验鱼80％-100％的死亡。根据对菌株的形态和生化特性的测定结果，11个菌株中的BH-001，BH-005，BH-009和BH-011等4个菌株属于叉尾(鱼回)爱德华菌(Edwardsiella ictaluri)，而BH-002，BH-015，BH-017和BH-019等4个菌株属于嗜水气单胞菌(Aeromonas hydrophila)。而BH-004，BH-013和BH-016等3个菌株尚未能鉴定其种类。更多还原

【Abstract】 This paper had three sections. The first section was mainly on investigation andcontrol of the bacterial disease in Nile tilapia of culture entirely in the last two years.According to nearly two years investigation from 2005 to 2006, the 15 kinds of speciesbacterial diseases of the cultured Nile tilapia was observed in the two years and this paperpresents the epizoology, mortality, diagnosis and control methods for these diseasesrespectively. We hope that it can make reference to the production of practice andinstitute together.The second section illustrated the results of the studies on the isolation andidentification of pathogens "exophthalmic" disease in Nile tilapia. From May to Octoberin 2006.in Zhangzhou, Fujian province and Guangzhou, Guangdong province, theartificial cultured Nile tilapia occured infection diseases continuously, the main symptomsof the infected fish which had a bad eating and inactive response, growing slowly andbecoming eccentric. Generally speaking the infected Nile tilapia had a obvious symptomswas that the eyes came out and showed gray white, sometimes the two eyes wereexophthalmic, sometimes only one eye, sometimes the whole eyes in serious infected fishand some accompanying with a little gill-rot disease. After dissecting, the diseased fishhad a abdominal dropsy proportional, the kidney had decayed and blooded, the liver hadshallow yellow spots which is susceptible. The gall swelled 2 to 4 times than normallywhich showed dark green, the intestine was empty and white which had yellow mucusand had little food, the gills, the fins and the skins of the diseased fish congested andblooded.Firstly, the 3 strain were isolated from the eyes, the liver, the kidney and the spleenof the "Exophthalmic" Disease of Nile tilapia, in zhangzhou Fujian province afterartificial infection by injection and immersion, three of the isolates were all proved to bethe pathogens of the disease. Through the morphological, physiological and biochemicalcharacteristics of the isolates it is identified to be the Shigella dysenteriae, Combing withAPI. The bacteria are Gram-negative and not motive short rods. Secondly, according toK-B methods, measuring the diameter of the inhibitory ring, it can sieve some good drugs,the results showed that the bacterium was highly sensitive to Ampicillin, Carbenicillin,Erythromycin, Doxycycline, Norfloacin, Kanamycin, not Furazolidone,Sulfamethoxazole/Time thoprin, Gentamycin and Sulfamethoxazole and then measuringthe minimum inhibitory concentration (MIC) and the minimum bactericidal concentration(MBC) in vitro. After it was orally administrated (4.0/μg/g, once a day for three days) thesecond day, the mortality becomes smaller obviously and the third the mortality stopped, it showed a good treatment to the disease of the tilapia.Formalin, phenol and heat killed cells of S.dysenteria were prepared to showimmunogenicity to mice, by examination of agglutinating antibody titer of serum of theKunming mice 31days later, it proved that 3 bacterins made by 3 methods showingstronger immunogenicity and the Formalin killed S.dysenteria showed the strongestimmunogenicity among three bacterial preparations and phenol killed shigella dysenteriashowed stronger immunogenicity than the heat killed S.dysenteriaThe third section illustrated the pathogenic bacteria were isolated from the diseasedchannel catfish (Ictalurus punctatus) and then identified. Healthy channel catfish wereinfected by injection and immersion with 19 strains of the isolated bacteria. Among the 19strains, 11 strains induced 80%-100% mortality. According to the morphological featureand biochemical characteristics of the isolates, strain BH-001, BH-005, BH-009 andBH-011Y62001 belong to Edwardsiella ictaluri, strain BH-002, BH-015, BH-017andBH-019 belong to Aeromonas hydrophila.更多还原