中文摘要：

本研究设计针对猪繁殖与呼吸综合征病毒（PRRSV）ORF7基因的特异性引物和TaqMan荧光探针，建立了一种检测PRRSV的快速、敏感、特异和重复性好的TaqMan荧光定量RT-PCR方法。该方法在检测10^1拷贝／μL～10^7拷贝／μL模板范围内具有良好的线性关系，比常规RT—PCR更敏感，可分别检测最少为10拷贝的阳性标准品和1TCID。病毒。用建立的方法检测高致病性变异株HuN4第5代和第65代体外传代细胞毒人工感染6周龄～7周龄仔猪后的0h、3h、5h、7h、10h、14h、21h血清样品，以及HuN4第5代病毒攻击仔猪21d后迫杀的猪的脑、心、肝、脾、肺、肾和淋巴结等组织样品病毒含量，结果发现HuN4第5代病毒感染仔猪3d后在血液中迅速复制，并在感染后7d血清病毒含量达到最高峰，接近10^10拷贝／mL。攻毒21d后，上述内脏组织中肺脏含毒量最多，接近10^9拷贝／g。HuN4第65代病毒在人工感染猪后21d的血清病毒含量最高，达到10^6拷贝／mL血清。

英文摘要：

A quantitative Taq Man reverse transcription-polymerase chain reaction （RT-PCR） for detecting PRRSV was developed using specific primers and fluorogenetic probe based on the ORF7 gene of porcine reproductive and respiratory syndrome virus （PRRSV）. The established method was highly specific, sensitive and reproducible. It had a linear dynamic range of the 10^1 copies/μL to 10^7 copies/μL and could detect the least 10 copies of target DNA and 1 TCID50 virus. The assay was succesffuly used to test on serum and tissue samples collected infected with the fifth passage PRRSV exhibitedd 10^10 copies/mL on day 7, while pigs infected with the on day 21. The virus concentrations in the lung were from experimentally infected pigs at various times following infection. Pigs a rapid increase in virus load in serum on day 3 and reached a peak of sixty-fifth passage virus had a lower virus load which peaked at 10^6 copies/mL 10^9 copies/g, which was much higher than that in other tissues.