猪伪狂犬病病毒HP-SY2022株的分离鉴定

Isolation and Identification of Porcine Pseudorabies Virus HP-SY2022 Strain and Sequence Analysis of gD and gE Genes

关键词:  伪狂犬病毒  变异株  分离鉴定  遗传序列分析

Key words:  Pseudorabies virus  mutant strain  isolation and identification  Genetic Sequence Analysis

摘要:

为了解猪伪狂犬病病毒(Pseudorabies virus,PRV)野毒株的特点,本研究对沈阳某养殖场疑似感染PRV的组织病料进行PCR鉴定、病毒分离和纯化、gD、gE基因序列测定及分析、动物回归实验。结果显示：分离株能在ST细胞中产生典型的细胞病变,且PCR显示为PRV阳性；通过gD、gE基因进行序列分析发现,分离株与2011年后分离的PRV变异株位于同一进化分支；氨基酸位点分析发现分离株与PRV变异株具有相同的变异模式。进一步研究其致病性,将纯化后的病毒液接种PRV抗体阴性21日龄健康仔猪,感染仔猪出现典型的PR症状,如呼吸困难、转圈、流涎和划水动作,且在试验期内仔猪全部发病(5/5),其中4头死亡(4/5)。综上,本研究成功分离到一株PRV变异株,将其命名为HP-SY2022。这一研究为丰富我国PRV分子流行病学及后续的免疫防控提供了参考。

Abstract:

To understand the characteristics of wild strains of porcine pseudorabies virus (PRV), This study conducted PCR identification, virus isolation and purification, gD, gE gene sequencing and analysis, and animal regression experiment on tissue samples suspected of PRV infection from a breeding farm in Shenyang. The results showed that the isolated strain could produce typical cytopathic effect in ST cells, and the PCR showed that it was PRV positive; Through sequence analysis of gD and gE genes, it was found that the isolates were located in the same evolutionary branch as PRV mutants isolated after 2011; Amino acid site analysis showed that the isolates and PRV mutants had the same variation pattern. To further study its pathogenicity, the purified virus liquid was inoculated into 21 day old healthy piglets with PRV antibody negative. The infected piglets showed typical PR symptoms, such as dyspnea, circling, salivation and paddling. During the test period, all piglets became ill (5/5), of which 4 died (4/5). In conclusion, a PRV mutant was successfully isolated and named HP-SY2022. This study provides a reference for enriching the molecular epidemiology of PRV and the subsequent immune prevention and control in China.