摘要: |
从四川眉山与新津两地患红头病的养殖黄颡鱼体内分离到2 株优势菌(CHNYC001 与 CHNYC002), 以腹腔注射与浸泡的方式进行人工感染试验, 证实其为养殖黄颡鱼红头病的病原菌。根据分离菌株的形态、生理生化特性, 结合16S rDNA 序列测定(GenBank 登录号分别为FJ766524、FJ766525)与系统发育分析, 将其鉴定为鮰爱德华氏菌(Edwardsiella ictaluri)。分离菌株最适生长温度为20—30℃, 最适生长pH 为7.0, 在含盐量2%以上的培养基上不生长, 对氟苯尼考、强力霉素、洛美沙星等敏感, 对乙酰螺旋霉素、磺胺甲基异噁唑和麦迪霉素等不敏感。临床病理特征分析发现, 养殖黄颡鱼感染鮰爱德华氏菌临床上分为急性与慢性两种类型, 急性型主要表现为败血症的病变特征,慢性型表现为头顶出血, 发红与溃疡的病变特征。
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关键词: 黄颡鱼, 红头病, 鮰爱德华氏菌, 分离鉴定, 生物学特性 |
DOI:10.11693/hyhz201001008008 |
分类号: |
基金项目:教育部“长江学者和创新团队发展计划”创新团队项目资助, IRTO848 号; 四川省教育厅重点项目资助, 08ZA082 号 |
附件 |
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ISOLATION, IDENTIFICATION AND BIOLOGICAL CHARACTERIZATION OF EDWARDSIELLA ICTALURI FROM CULTURED YELLOW CATFISH PELTEOBAGRUS FULVIDRACO |
GENG Yi, WANG Kai-Yu, FAN Fang-Ling, CHEN De-Fang, HUANG Jin-Lu
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Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University
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Abstract: |
Bacterial strains CHNYC001 and CHNYC002 were isolated from cultured yellow catfish Pelteobagrus fulvidraco with red-head disease in Meishan and Xinjin counties, Sichuan Province. The strains were proved to be the pathogens of the disease in our challenging experiments by immersion and intraperitoneal injection. The isolated strains were identified as Edwardsiella ctaluri in morphology, physiology and biochemistry, as well as 16S rDNA sequence (Accessible Number in GenBank: FJ766524, FJ766525). The optimum temperature and pH for the strains growth was 20—30℃ and 7.0. The strains grew normally at <2% in salinity of the culture medium. The results also show that the strains were sensitive to florfenicol, doxycycline, and lomefloxacin, but to acetylspiramycin, sulfamethoxazole, and medemycin. Clinical and pathological study revealed two types of the Edwardsiella ictaluri-induced disease in yellow catfish: acute and chronic. The acute type featured mainly septicemia, necrosis, haemorrhage, and inflammatory reaction in multi-organs and tissues, while the chronic one showed hemorrhage and ulcer on head, instead.
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Key words: Pelteobagrus fulvidraco, Red-head disease, Edwardsiella ictaluri, Isolation, Identification, Biological characteristics |