两株草鱼呼肠孤病毒江西株的分离与鉴定

Isolation and identification of two grass carp reovrius strains in Jiangxi province

对从江西省南昌县莲塘镇的患病草鱼鱼种池塘采集到草鱼出血病疑似病样材料分离出的两株病毒株进行了鉴定。结果显示:用除菌过滤后的患病鱼肝脏、脾脏、肾脏组织浆滤液腹腔注射感染8～10 cm健康草鱼鱼种,5 d后试验鱼发病,可复制出自然发病症状,死亡率达50%以上,对照组未有死亡。用病样滤液接种草鱼肾细胞系(CIK),可产生细胞病变效应(CPE),病毒的TCID50分别为10-8.3/0.1 mL和10-8.0/0.1 mL。理化特性研究结果显示:氯仿、乙醚处理组病毒的感染力和对照组相比变化不显著。病毒基因组RT-PCR反应可扩增出目的片段,序列测定与分析结果表明,其与GenBank中GCRV(登录号为AF403392,AF239175)相应序列的同源性达99%以上。

Two strains of novel reovirus had been isolated from the diseased grass carp with hemorrhagic symptom from Nan Chang County in Jiangxi province.The homogenates of visceral organs of diseased fish was filtrated and injected to healthy grass carp fingerlings separately.The typically clinical signs of hemorrhagic symptom as naturally occurred could be replicated in five days,and the mortality reached above 50%,while there was no death in centred group.The two samples were inoculated onto CIK cells and they could cause typical cytopathic effect（CPE） in cells.The TCID50 of the two isolated virus strains were 10-8.3/0.1 mL and 10-8.0/0.1 mL respectively.Physico-chemically,the two isolated strains were not sensitive to chloroform and ether.436 bp nucleotide segments were amplified respectively from the isolated strains by reverse transcription polymerase chain reaction（RT-PCR）.The nucleic acid sequences of the two amplified segments had been sequenced and the results showed 99% homology with that of the GCRV（AF403392 and AF239175） strains in Gene Bank.