摘要
2022年3月四川省乐山市某养殖场的鲤出现大面积死亡,累计死亡率80%。为研究此次疾病的病因和流行规律,将病料解剖,进行病理学检查、细菌学检查、PCR鉴定,以及病毒分离鉴定与系统进化分析。结果显示,病理学病变主要在鳃和肠道,肠道充血、出血,上皮细胞坏死脱落;鳃小片上皮细胞增生、坏死、脱落。根据病理学诊断初步判断患病鱼为鲤春病毒血症病毒(Spring viremia of carp virus,SVCV)感染。RT-PCR检测结果显示,在自然发病鲤、人工感染发病鲤的内脏组织和细胞培养病毒液中均扩增出SVCV的G蛋白基因序列。细胞培养病毒液的超薄切片电镜观察结果显示,病毒粒子长80~150 nm,宽40~60 nm,呈子弹状。人工感染细胞培养病毒液的健康鲤出现与自然发病鲤相似的临床症状,感染组累计死亡率为65%。通过鲤上皮瘤细胞(epithelioma papulosum cyprini cell,EPC细胞)培养分离得到1株病毒,全基因组测序与系统进化分析结果表明,该分离株与SVCV的同源性最高,将该分离株命名为SVCV-2022。结合本次疾病的流行特点与病理诊断、病毒分离鉴定和人工感染试验,确定此次传染病的病原为SVCV。
In March 2022,large scale death of carp from a farm in Leshan City,Sichuan Province,suddenly developed acute mortality with a cumulative mortality rate of 80%.To study the etiology and epidemiological pattern of this disease,the diseased material was subjected to autopsy,pathological examination,bacteriological examination,PCR identification,virus isolation and identification and phylogenetic analysis.The results showed that histopathological lesions were mainly in the gills and intestines,intestinal congestion and hemorrhage,with necrosis and shedding of epithelial cells;and hyperplasia,necrosis and shedding of epithelial cells in gill lamellae.Based on pathological diagnosis,it was preliminarily determined that the disease was caused by Spring viremia of carp virus(SVCV)infection.RT-PCR detection results showed that the G protein gene sequence of SVCV was amplified in the visceral tissues and cell culture virus solution of naturally infected carp and artificially infected carp.Electron microscopic observation of ultrathin sections of cell cultures virus solution showed that the viral particles were 80-150 nm long and 40-60 nm wide,and were bullet-shaped.Artificially infected healthy carp showed clinical symptoms similar to those of naturally infected carp,with a cumulative mortality rate of 65%in the infected group.A virus strain was isolated from epithelioma papulosum cyprini cell(EPC),and whole genome sequencing and sequence analysis were performed on the isolate,which was named SVCV-2022 after sequencing conformation of the highest homology with SVCV.Combining the epidemiological and pathological characteristics of the disease,the isolation and identification of the virus,the results of the artificial infection test and transmission electron microscopy,the pathogen of the epidemic was identified as SVCV.
作者
祁英吉
刘舒亚
兰寒韵
王雪梅
孙甜甜
李书含
黎秋男
黄小丽
耿毅
陈德芳
欧阳萍
QI Yingji;LIU Shuya;LAN Hanyun;WANG Xuemei;SUN Tiantian;LI Shuhan;LI Qiunan;HUANG Xiaoli;GENG Yi;CHEN Defang;OUYANG Ping(College of Veterinary Medicine,Sichuan Agricultural University,Chengdu 611130,China;College of Animal Science and Technology,Sichuan Agricultural University,Chengdu 611130,China)
出处
《浙江农业学报》
北大核心
2025年第7期1430-1440,共11页
Acta Agriculturae Zhejiangensis
基金
四川农业大学科研兴趣培养项目(20241107)。
关键词
鲤春病毒血症病毒
鲤
累计死亡率
系统进化分析
Spring viremia of carp virus
carp
cumulative mortality rate
phylogenetic analysis
