【作者】 刘国勇；

【导师】 陈昌福；

【作者基本信息】 华中农业大学 ， 水产养殖， 2001， 硕士

【摘要】 本论文介绍了作者对大黄鱼弧菌病及其防治对策的研究结果。2000年5月上旬至8月上旬，浙江省宁波市象山港网箱养殖大黄鱼陆续发病，主要症状有两种，一种为皮肤溃疡、尾鳍烂蚀，另一种为病鱼停食，胃肠内无食物，内脏肿大，后肠充满黄色粘液。首先，从浙江省宁波市象山港内养殖网箱中患病大黄鱼上分离到5个菌株，经注射和浸泡法人工感染试验，证明其中4个菌株能导致供试大黄鱼100％的死亡。根据对菌株的形态和生化特性等40多项指标的测定结果，证明了本研究中分离到的5个菌株分属于2种不同的弧菌，Y62001和Y80721等2个菌株属于哈维氏弧菌(Vibrio harveyi)，而Y70301、Y70701和Y80704等3个菌株属于副溶血弧菌(Vibrio parahaemolyticus)。 其次，在试管内测定了12种抗菌药物(氨苄青霉素，链霉素，盐酸四环素，新霉素，氯霉素，麦迪霉素，环丙沙星，螺旋霉素，诺氟沙星，喹塞多，嚼喹酸，先锋霉素Ⅳ)对大黄鱼弧菌病的致病菌，V.harveyi和V.parahaemolyticus等2种弧菌的抑、杀菌效果，证明了环丙沙星和诺氟沙星等2种抗菌药物对2种弧菌均具有较好的抑、杀菌作用；而氨苄青霉素等10种抗菌药物的最小抑菌浓度(MIC)和最小杀菌浓度(MBC)较高，证明2种弧菌已经对这10种抗菌药物产生了抗药性。将环丙沙星和诺氟沙星按5.0μg／g鱼体重的用药量拌和在饲料中，投喂养殖网箱中患病的大黄鱼，在用药后的第2d，死亡率大幅度下降，连续用药3d后，即停止了死亡。证明了环丙沙星和诺氟沙星对大黄鱼的弧菌病有很好的疗效。 其三，将V.harveyi制各成福尔马林灭活菌苗(F-VH)、苯酚灭活菌苗(P-VH)、热灭活菌苗(H-VH)，分别注射接种异育银鲫后，通过测定受免鱼血清中凝集抗体效价和血液中自细胞的吞噬活性，对不同方法制备的菌苗的免疫原性进行了比较。结果表明，3种方法制备的V.harveyi菌苗注射接种异育银鲫后第29d，受免异育银鲫血清中凝集抗体效价均不同程度地上升，其中以F一VH免疫组最高，P一VH免疫组其次，再次为H一VH免疫组。而对照鱼血清中凝集抗体效价都很低。对受免和对照异银卿血液中白细胞对福尔马林灭活的金黄色葡萄球菌(F一SA)的吞噬活性的测定结果表明，受免异育银卿血液中白细胞的吞噬百分比(PP)和吞噬指数(Pl)，均显著地高于对照组。这些结果表明，用3种方法制备的犷harVeyi菌苗对异育银铆均有较强的免疫原性，而以F一vH的免疫原性最强，其次是P一VH，H一VH的免疫原性较弱。更多还原

【Abstract】 From May to August in 2000, in Xiangshang Bay, Ningbo, Zhejiang province, the net-cage cultured large yellow croaker (Pseudosciaena croced) occurred infection diseases, the infected fish showed two types of main symptoms: one type, the skin festered and the caudal fin rotted; the other type, the infected fish was anorexia, it’s stomach and intestine were empty, and the end intestine was full of yellow mucus. Five strains were isolated from the liver, kidney and spleen of the infected fish. Four of them were proved to be the causative agent after artificial infection. The five strains showed the morphological, physiological, and biochemical characteristics of the genus Vibrio. And according to the results of over 40 tests, comparison to the data of Bergey’s Manual of Determinative Bacteriology (9th, edition), 2 and 3 strains seemingly belong to two different species, Vibrio harveyi and Vibrio parahaemolyticus, respectively.In vitro, efficacies of antibiotics were tested on pathogenic bacteria fromPseudosciaena crocea infected with vibriosis--Vibrio harveyi (the strainY62001 and Y80721) and Vibrio parahaemolyticus (the strain Y70301, Y70701and Y80704 ). Twelve antibiotics, namely, Ciprofloxacin , Norfloxacin , Ampicillin , Tetracycline , Streptomycin , Neomycin , Chloramphenicol, Midecamycin, Spiramychin, Cyadox, Oxolinic arid, Cephalexin were studied. The efficacies of the antibiotics on five strains were determined as well as minimum inhibitory concentrations (MIC) and minimum bactericidal concentrations (MBC). The two strains showed high susceptibilities to Ciprofloxacin and Norfloxacin, while the two strains showed low susceptibilities to the other ten antibiotics. It was showed that Ciprofloxacinand Norfloxacin exhibited chemotherapeutic effects on Pseudosciaena crocea infected with vibriosis when it was orally administered (5.0 g/g, once a day for three days).Formalin and phenol and heat killed cells of Vibrio harveyi were prepared to show immunogenicity to Caressius auratus gibel by examination of agglutinating antibody litres of serum as well as phagocytic activity of blood leucocytes. It was proved that three bacterins mady by three methods showing strong immunogenicity and formalin-killed V. harveyi showed the strongest immunogenicity among three bacterial preparations and phenol-killed V. harveyi showed stonger immunogenicity than heat-killed V. harveyi.更多还原