猪伪狂犬病毒流行株的分离鉴定及其毒力试验

Isolation、Identification and Virulence Test of Pseudorabies Virus Epidemic strains

本研究采集了猪伪狂犬病阳性样品,通过PK-15细胞对PRV流行毒株进行了分离培养、纯净性检验、中和试验鉴定、遗传进化分析和仔猪毒力试验,对我国当前流行的猪伪狂犬病毒的遗传变异与毒力变化情况进行了分析。通过病毒分离鉴定共获得6株猪伪狂犬病毒,其中SCY1株、HBA1株、JXN1株存在支原体或PCV2污染,SCHS株、SCM1株、JXHS株无外源污染,并能被猪伪狂犬病毒特异性血清中和。6个分离毒株的gB基因片段与JS-2012株的同源性为99.7%~100%,与Bartha K61株的同源性约为95%;gC基因片段与JS-2012株的同源性为99.5%~100%,与Bartha K61株的同源性为90.7%~91.2%;gD基因与JS-2012株的同源性为99.8%~100%,与Bartha K61株的同源性在98.7%~98.9%之间;gE基因与JS-2012株的同源性在99.1%~99.8%之间。用3株纯净毒株感染8~9周龄PRV抗体阴性仔猪后全部出现体温升高,部分试验猪出现呼吸道症状并死亡。试验结果表明,本次分离的猪伪狂犬病毒与我国当前流行毒株的遗传关系接近,但不同毒株的毒力存在一定差异。

In this study,we isolated PRV field strain from PRV positive samples,the purity,neutralization virulence test and genetic evolution analysis were performed. A total of 6 PRV strains were obtained through virus isolation. Among them,SCY1,HBA1 and JXN1 strains were contaminated with Mycoplasma or PCV2. The SCHS,SCM1 and JXHS strains were pureness and specific to the PRV positive serum. The homology of the gB gene between the 6 isolated strains and the JS-2012 strain was 99.7% to100%,and that of the Bartha K61 strain was about 95%. The homology of the g C gene fragment between the 6 isolated strains and the JS-2012 strain was 99.5% to 100%,and that of the Bartha K61 strain was90.7% to 91.2%. The homology of g D gene between the 6 isolated strains and the JS-2012 strain was99.8% to 100%,that of the Bartha K61 strain was 98.7% to 98.9%. The homology of gE gene between 6 isolated strains and JS-2012 was between 99.1% and 99.8%. 8 to 9 weeks old piglets infected with SCHS, SCM1 or JXHS caused high fever, anorexia, some respiratory symptoms or death. The results showed that the PRV filed strains is closely related to the epidemic strains in China,however,the virulence of different strains was different.