传染性肌肉坏死病

2008年农业部兽医局委托动物流行病学中组织专家编写动物疫病释义,为便于解读水生动物的疫病,本刊现将《一、二、三类动物疫病病种名录》中水生动物疫病种类的分类及各病的释义分期进行刊登。     

鲍病毒性死亡病

鲍病毒性死亡病,也称为鲍病毒病、鲍裂壳病,是严重威胁我国南北鲍养殖的一种疾病.为我国水生动物三类疫病.一、病原学病原是一些鲍球形病毒(Abalone spherical viruses),其分类地位不详.包括四种球形病毒:第一种直径90nm～140nm,有二层囊膜(8nm～10nm)和光滑的表面,核衣壳直径70nm～100nm.在血细胞或者结缔组织的细胞质里复制;第二种直径100nm,有囊膜.核衣壳为六边形(或二十面体),在肝、肾和肠道的上皮细胞质里复制,通常在内质网里,是DNA病毒;第三种直径135nm～150nm纳米,有囊膜,表面有突起.二十面体的核衣壳直径为100nm～110nm.在受感染的肝、肾细胞(包括上皮细胞和结缔细胞)的细胞质中有双层膜的空泡里装配;推测它们在细胞核里复制;第四种直径90nm～110nm,有光滑表面的囊膜,二十面体的核衣壳,在受感染的肝、肾细胞(包括上皮细胞和结缔细胞)的细胞质中有双层膜的空泡里装配二十面体的核衣壳;推测它们在细胞核里复制.     

水生动物疫病病种介绍：传染性造血器官坏死

2008年农业部兽医局委托动物流行病学中组织专家编写动物疫病释义,为便于解读水生动物的疫病,本刊现将《一、二、三类动物疫病病种名录》中水生动物疫病种类的分类及各病的释义分期进行刊登。     

黏孢子虫病

2008年农业部兽医局委托动物流行病学中组织专家编写动物疫病释义,为便于解读水生动物的疫病,本刊现将《一、二、三类动物疫病病种名录》中水生动物疫病种类的分类及各病的释义分期进行刊登。     

小瓜虫病Ichthyophthiriasis

2008年农业部兽医局委托动物流行病学中组织专家编写动物疲病释义,为便于解读水生动物的疫病,本刊现将《一、二、三类动物疫病病种名录》中水生动物疫病种类的分类及各病的释义分期进行刊登。     

闽南地区养殖石斑鱼病毒性神经坏死病初步研究

应用流行病学调查方法。对发生在福建南部海区网箱养殖石斑鱼的暴发性传染病进行了初步研究。应用PCR和RT-PCR技术。检测石斑鱼常见的病毒性神经坏死病病毒、真鲷虹彩病毒,结果各发病渔场均检出病毒性神经坏死病病毒;病原菌分离未发现强致病性细菌;寄生虫检查发现腹腔普遍有一种微孢子虫感染形成的孢囊。临床症状主要表现为游动失常、厌食、鳔肿大、肾脏坏死、糜烂。表明病毒性神经坏死病病毒感染是导致石斑鱼大批死亡的主要原因。     

白斑综合征

2008年农业部兽医局委托动物流行病学中组织专家编写动物疫病释义,为便于解读水生动物的疫病,本刊现将《一、二、三类动物疫病病种名录》中水生动物疫病种类的分类及各病的释义分期进行刊登。     

鲍脓疱病

2008年农业部兽医局委托动物流行病学中心组织专家编写动物疫病释义,为便于解读水生动物的疫病,本刊现将《一、二、三类动物疫病病种名录》中水生动物疫病种类的分类及各病的释义分期进行刊登。     

草鱼出血病

2008年农业部兽医局委托动物流行病学中组织专家编写动物疫病释义,为便于解读水生动物的疫病,本刊现将《一、二、三类动物疫病病种名录》中水生动物疫病种类的分类及各病的释义分期进行刊登。     

折光马尔太虫病

折光马尔太虫病,是由折光马尔太虫寄生于牡蛎、贻贝等双壳类动物消化系统的一种寄生虫病,牡蛎染疫后表现虚弱、消瘦、生长停滞和高死亡率.为OIE疫病和我国水生动物三类疫病.     

Viral nervous necrosis (VNN) associated with mass mortalities in cage-reared sea bass,Dicentrarchus labrax (L.)

Mass mortalities of the European sea bass, Dicentrarchus labrax (L.), occurred in different ongrowing units in Greece. A presumptive diagnosis of viral nervous necrosis (VNN) was made on the basis of the light microscopic observations of a vacuolating encephalopathy and retinopathy. Positive peroxidase reaction with VNN antiserum confirmed nodavirus as the causative agent. Usually recorded in larvae and juvenile stages of different marine fish species, VNN is described in adult sea bass and sea bass reared in floating cages in the Mediterranean for the first time. The horizontal transmission of the disease has been strongly suspected. Histological analyses clearly demonstrate that cells other than nerve cells are also infected. Some epidemiological aspects of the disease are described and their implications for the establishment of prophylactic guidelines are discussed.     

Protective immunity of sevenband grouper, Epinephelus septemfasciatus Thunberg, against experimental viral nervous necrosis

This paper describes the protective immune responses of sevenband grouper, Epinephelus septemfasciatus Thunberg, immunized with live piscine nodavirus, the causative agent of viral nervous necrosis (VNN), or the Escherichia coli – expressed recombinant coat protein. Nodavirus-neutralizing antibodies were detected at titres ranging from 1:158 to 1:1257 in serum of sevenband grouper which survived intramuscular injection with the virus, by a cell culture assay system. The virus-neutralizing ability of immune serum was also confirmed by injecting virus previously treated with serum into fish. This indicates establishment of acquired immunity in survivors and thus explains why survivors from natural infection are resistant to recurrence of the disease. Young sevenband grouper were immunized twice by intramuscular injections with the recombinant coat protein. Immunized fish produced neutralizing antibodies at high titres for at least 110 days and showed significantly lower mortalities in virus challenge tests. These results suggest the potential for vaccination against VNN in sevenband grouper, which is susceptible to piscine nodavirus at all life-stages.     

斜带石斑鱼神经坏死病毒CP基因shRNA干扰载体的构建及效果评价

利用Invitrogen公司的在线生物学软件分析斜带石斑鱼神经坏死病毒CP基因,设计针对CP基因不同位置的小发卡RNA( short hairpin RNA,shRNA)干扰序列[其结构特征为正链( 19 nt) -环(4 nt) -负链(19 nt)].化学合成这些序列,并退火连接为双链干扰片段,将双链干扰片段定向克隆到干扰载体pENTRTM/U6中,构建shRNA干扰载体pshRNA -124、pshRNA-896和pshRNA-NNV.然后,用脂质体转染法分别将3种shRNA干扰载体和pEGFP-CP基因共转染导入黑头呆鱼(FHM)肌肉细胞,荧光显微镜观察细胞荧光强度,分析荧光抑制效率,Real-time RT-PCR检测CP基因mRNA的表达水平变化.结果表明,在pEGFP-CP与shRNA干扰载体共转染组,pshRNA-124、pshRNA-896、pshRNA-NNV的荧光抑制效率分别为47％、68％、51％.3种shRNA干扰载体都有干扰效果,均能干扰绿色荧光蛋白的表达,其中pshRNA-896干扰效率最好.Real-time RT-PCR检测表明,干扰质粒pshRNA-124、pshRNA-896、pshRNA-NNV对pEGFP-CP基因的沉默效率分别约为60％、96％和55％,与对照组相比差异显著(P＜0.05).研究表明,靶向斜带石斑鱼神经坏死病毒CP基因的shRNA干扰载体构建成功,为进一步运用RNA干扰技术进行CP基因的功能研究奠定了基础.     

Histopathological studies on viral nervous necrosis of sevenband grouper, Epinephelus septemfasciatus Thunberg, at the grow-out stage

Abstract Viral nervous necrosis caused by sevenband grouper nervous necrosis virus (SGNNV) has occurred in grow-out stages (0-3 years old) of sevenband grouper, Epinephelus septemfasciatus, since the 1980s. In the present study, based on histopathological features of the central nervous system (CNS) in naturally diseased fish, pernasal infection experiments using grow-out fish were performed and pernasal infection was established as a putative invasion route of SGNNV. The definite SGNNV-targeted cells were determined by histopathological studies including indirect fluorescent antibody test and electron microscopy. Nerve cells in the olfactory lobe were most extensively necrotized with vacuolation followed by infiltration of microglia and macrophages. Purkinje cells and Golgi cells were extensively infected in the cerebellum. Megalocells and small nerve cell nuclei were also infected in the preoptic area, thalamus, medulla oblongata and spinal cord. Only a few small nerve cells were infected in the olfactory bulb and optic tectum. The retina of some diseased fish displayed vacuolated bipolar cells of the inner nuclear layer and in the ganglion cell layer. These SGNNV-infected nerve cells displayed viroplasmic inclusions containing virions, vacuoles and myelin-like structures. Based on observed histopathological changes, the lesion of the CNS was characterized by encephalitis but not encephalopathy.     

病毒性出血性败血病

病毒性出血性败血病（Viral haemorrhagic septicaemia,VHS）是由弹状病毒引起鲑、鳟、狗鱼和大菱鲆的一种烈性传染病,表现为出血性败血症,致死率极高。本病主要流行于欧洲及北美,是世界动物卫生组织（OIE）必须申报的疫病,我国将其列为二类疫病。     

Complete sequencing of Tunisian redspotted grouper nervous necrosis virus betanodavirus capsid gene and RNA‐dependent RNA polymerase gene

Finfish nodaviruses (betanodaviruses) can cause highly destructive infections in numerous species of farmed marine fish larvae and juveniles worldwide. The betanodavirus genome consists of two single‐stranded positive‐sense RNA molecules (RNA1 and RNA2). The virus can be classified into four genotypes based on the partial sequences of the coat protein (CP) gene (T2 and T4 regions). Currently, genomic sequence information for RNA1 regions of RNA2 outside of T2 and T4 is less well documented. This study reports on the characterization of the full RNA2 sequence of a Tunisian betanodavirus with a length of 1433 nt, containing a 339 amino acid open‐reading frame encoding the CP, and typing to the redspotted grouper nervous necrosis virus Ia genotype following phylogenetic analysis. The homology of the capsid protein to other betanodaviruses or alphanodaviruses was compared. In addition, a full length RNA1 sequence of 3104 nt encoding a 982 amino acid RNA‐dependent RNA polymerase was obtained.