文章摘要
真鲷虹彩病毒引起养殖斑石鲷大规模死亡的研究
Rea Seabream Iridovirus Causing Mass Mortality in Farmed Spotted Knifejaw, Oplegnathus punctatus
投稿时间:2019-04-30  修订日期:2019-05-09
DOI:
中文关键词: 斑石鲷  真鲷虹彩病毒  肿大细胞虹彩病毒  系统发育树  诊断
英文关键词: Spotted knifejaw  Oplegnathus punctatus  Red sea bream iridovirus (RSIV)  Megalocytivirus  Phylogenetic tree  Diagnosis
基金项目:农业国际交流与合作项目, 中国水产科学研究院中央级公益性科研院所基本科研业务费专项资金
作者单位E-mail
王海波 中国水产科学研究院黄海水产研究所, 上海海洋大学 1768510759@qq.com 
史成银 中国水产科学研究院黄海水产研究所, 青岛海洋科学与技术试点国家实验室海洋渔业科学与食物产出过程功能实验室, 农业农村部海水养殖病害防治重点实验室, 青岛市海水养殖流行病学与生物安保重点实验室 shicy@ysfri.ac.cn 
谢国驷 中国水产科学研究院黄海水产研究所  
刘冉阳 中国水产科学研究院黄海水产研究所  
任宁欣 中国水产科学研究院黄海水产研究所, 上海海洋大学  
摘要点击次数: 35
全文下载次数: 0
中文摘要:
      斑石鲷是我国海水养殖鱼类新品种,经济价值高。2017年8月,某养殖场网箱养殖的斑石鲷幼鱼突然发病并大量急性死亡。疾病调查显示,养殖海域水温26—28℃;病鱼4—5月龄,全长16.3±1.6 cm,体重156.9±37.0 g;80万尾斑石鲷幼鱼2周内累积死亡率达90%以上,经济损失惨重。临诊检查发现,病鱼体表无明显损伤,但活力差、呼吸急促。剖检可见病鱼脾肿大、质地脆、易碎;肾糜烂,肝有出血点。组织切片观察,病鱼脾、肾造血组织中可见许多直径约20 μm的肿大细胞,肿大细胞内含有大量直径约145 nm、呈六边形的病毒颗粒。用过滤除菌的病鱼脾组织匀浆液,腹腔注射感染健康斑石鲷,感染组鱼14 d内累积死亡率达95%。人工感染病鱼表现出与自然发病鱼类似的外观症状,且在脾、肾组织切片中也可观察到大量的肿大细胞及相似的病毒粒子。使用特异性的PCR引物,从自然发病鱼和人工感染病鱼的肝、脾和肾组织中均检测到鱼类虹彩病毒的高强度感染。克隆、测序得到了1362 bp的病毒主要衣壳蛋白(major capsid protein, MCP)基因,序列比对显示该病毒的MCP基因序列与真鲷虹彩病毒(red sea bream iridovirus, RSIV)RIE12-1的相应序列100%相同。构建的虹彩病毒系统发育树也显示该病毒属于虹彩病毒科肿大细胞病毒属RSIV类群,是RSIV的一个分离株。本研究首次证实RSIV可以导致斑石鲷大规模死亡,研究结果为诊断和防治斑石鲷病毒病提供了重要参考。
英文摘要:
      Spotted knifejaw (Oplegnathus punctatus) is a new species of mariculture fish with high economic value in China. In August 2017, an outbreak of unknown etiology occurred in the spotted knifejaw juveniles cultured in offshore cages of a marine fish farm. The investigation showed that the water temperature was 26–28°C and the infected fish were mainly juveniles at the age of 4–5 months. The total length of the diseased fish was 16.3±1.6 cm and the body weight was 156.9±37.0 g. The cumulative mortality of 800,000 juveniles was more than 90% within 2 weeks after the onset of the disease. Clinic examination showed that diseased juveniles had no obvious lesions apparently, but they had poor vitality and breathing rapidly. Necropsy findings included swollen and brittle spleen, erosion of kidney, hemorrhagic spots with liver. No parasites were detected and no pathogenic bacteria were isolated from the liver, spleen and kidney in the diseased fish. Histopathological sections showed that there were a large number of enlarged cells about 20 μm in diameter in the spleen and kidney tissues of diseased fish. In addition, a large number of hexagonal virus particles with a diameter of about 145 nm were observed in the electron microscope sections of the spleen and the body kidney. Spleen homogenate of naturally infected fish was filtered and then injected into healthy fish intraperitoneally at 26°C of water temperature. The fish in infected group began to die after 10 days post infection (dpi) and the cumulative mortality reached 95% within 14 dpi. Artificially infected fish showed the appearance symptoms similar to those of naturally infected fish, and a large number of enlarged cells and similar virus particles could be observed in spleen and kidney tissue sections. Severe infection of iridovirus was detected in the spleen and kidney tissues of naturally and artificially infected fish using specific PCR primers. The major capsid protein (MCP) gene with 1362 bp in length of the iridovirus was cloned and sequenced, and the phylogenetic tree of the family Iridoviridae was constructed. The results showed that the virus belonged to the red sea bream iridovirus (RSIV) of genus Megalocytivirus in the family Iridoviridae. Based on the results of epidemiological investigation, clinical symptoms observation, etiological detection, histopathological observation, artificial infection experiment, molecular biology diagnosis and viral phylogenetic analysis, it is confirmed that the disease causing the mass death of spotted knifejaw was Megalocytivirus disease, and the pathogen was a strain of RSIV. This study demonstrates for the first time that RSIV can cause large-scale death of spotted knifejaw. Furthermore, the research results provide an important reference to diagnose and control the viral disease of spotted knifejaw.
相关附件:   图1-7  图1-7原始文件  万方20190430(11.26%)  矢量图1-7  修改说明
View Fulltext   查看/发表评论  下载PDF阅读器
关闭