摘要
为了对分离于山东某虹鳟养殖场的一株传染性造血器官坏死病毒株（IHNV-Sn1203）进行致病性检测与研究,将该IHNV-Sn1203毒株进行虹鳟鱼苗人工回接感染实验。结果显示,8d内人工感染实验鱼累计死亡率高达100%。收集大批濒死的病鱼样本,制备病理组织切片;利用鲤上皮细胞（EPC）进行细胞感染实验、病毒电镜观察、空斑实验、病毒滴度检测和聚类分析。病理组织切片显示,该病毒可造成虹鳟造血器官广泛性坏死;细胞感染实验结果显示,接种24 h后EPC细胞出现葡萄串状典型细胞病变（cytopathic effect,CPE）,72 h后大部分细胞崩解脱落形成网状孔洞;电镜下清晰可见弹状病毒粒子大量存在于细胞质内,其在EPC细胞上的滴度为10^8.36TCID50/mL,并能形成2～4 mm空斑。对病毒核蛋白氨基酸序列的聚类分析结果显示,该病毒与标准毒株RB-1和WRAC的同源性分别为97%和93%,与国内报道的zyx株具有最高的同源性（99%）。研究表明,IHNV-Sn1203毒株能够在鱼体及敏感细胞中稳定繁殖,产生典型病变,具有较高的病毒滴度,对虹鳟鱼苗有很高的感染性和致死性。
In order to analyze the pathogenicity of a new strain of infectious haematopoietic necrosis virus（ IHNV-Sn1203） isolated from rainbow trout farm of Shandong Province,rainbow trout fry were subjected to artificial infection test. The artificial infection test showed an accumulated average mortality rate as high as100%（ 8 days）,and with typical symptoms. Diseased fish samples were collected,homogenized,filtered,then inoculated onto monolayer cultures of carp epithelial cell（ EPC）,and further analyzed with plaque assay,electron microscopy observation,virus titer detection and homology analysis. Cytopathic effect（ CPE）of the EPC cells can be observed 24 h after inoculation,most of the cells disintegrated off 72 h after inoculation. In EPC cells the virus titer was 10^8. 36TCID50/mL,and formed about 2 to 4 mm plaques.Rhabdovirus particles in large numbers were clearly observed in the cytoplasm by electron microscope.Phylogenetic tree was constructed based on the amino acid sequences of nucleoprotein. The results showed that the amino acid sequence of IHNV-Sn1203 nucleoprotein had 97% and 93% identity with RB-1 and WRAC,respectively,and had homology as high as 99% with the domestic zyx isolate. These results indicate that the IHNV-Sn1203 isolate can stably propagate in cells cultured in vitro with high viral titer,and can infect rainbow trout fry with high mortality.
出处
《水产学报》
CAS
CSCD
北大核心
2014年第9期1584-1591,共8页
Journal of Fisheries of China
基金
国家科技支撑计划(2012BAD25B02)
中央级公益性科研院所基本科研业务费专项(HSY201202)
黑龙江省冷水性鱼类种质资源及增养殖重点开放实验室(201104)
关键词
虹鳟
传染性造血器官坏死病毒
感染性
致病性分析
细胞病变
病理切片
rainbow trout
infectious haematopoietic necrosis virus
infectivity
pathogenicity analysis
cytopathic effect
pathology section
