Abstract: To distinguish JXA1-R vaccine strain and NADC30-like HNhx strain of porcine reproductive and respiratory syndrome virus(PRRSV),TaqMan real-time quantitative PCR and SYBR Green Ⅰ realtime quantitative PCR were established by using specific primers based on the difference of the regions of Nsp2 genes between HNhx and JXA1-R.The results indicated that the standard products had a good linear relationship in the range of 10³—10⁸ copies/μL,and the R² of the standard curves were over 0.990 in two methods.The detection limit of the TaqMan-based fluorescent quantitative PCR was 10⁴copies/μL(JXA1-R) and 10³copies/μL(HNhx),respectively.The detection limit of SYBR Green Ⅰ fluorescent quantitative PCR was 100 copies/μL.The reproducibility of intra-and inter-assay displayed that the coefficient of variations was less than 1.5%,the repeatability was good.In conclusion,the method for differentiation of HNhx and JXA1-R was successfully established in this study, which exhibited good stability and high specificity, and provided a new technical support for the differential detection of PRRSV.

Key words: PRRSV, JXA1-R vaccine strain, HNhx strain, TaqMan real-time quantitative PCR, SYBR Green Ⅰ real-time quantitative PCR, Differential detection

摘要： 为鉴别检测猪繁殖与呼吸综合征病毒（PRRSV）类NADC30毒株HNhx和JXA1-R疫苗株，根据类NADC30毒株HNhx和JXA1-R疫苗株非结构蛋白2（Nsp2）基因序列差异，设计特异性引物和探针，建立TaqMan荧光定量PCR和SYBR Green Ⅰ荧光定量PCR检测方法。结果显示，2种方法中，标准品在10³~10⁸ 拷贝/μL均具有良好线性关系，标准曲线R²值均在0.990以上；基于TaqMan探针法的荧光定量PCR方法，JXA1-R株、HNhx株的最低检出量分别为10⁴、10³ 拷贝/μL，SYBR Green Ⅰ荧光定量PCR方法的最低检出量均为100 拷贝/μL；重复性分析结果显示，批内和批间试验的变异系数均小于1.5%，呈现出良好重复性。综上，成功建立了鉴别检测类NADC30毒株HNhx和JXA1-R疫苗株的方法，且稳定性好、特异性强，可以为PRRSV的鉴别检测提供技术支持。

关键词: 猪繁殖与呼吸综合征病毒, JXA1-R疫苗株, HNhx毒株, TaqMan荧光定量PCR, SYBR Green Ⅰ荧光定量PCR, 鉴别检测