高致病性猪蓝耳病病毒重庆株的分离鉴定及其变异性分析

Identification and Genetic Diversity of Porcine Reproductive and Respiratory Syndrome Virus Isolated from Chongqing

摘要: 从重庆某猪场采集病死猪病料，经RT-PCR初步鉴定其病原为猪繁殖与呼吸综合征病毒后，利用反转录合成cDNA，设计NSP2和GP5基因片段的特异性引物，并对其扩增，序列测序，分析鉴定。结果表明，该分离株的NSP2基因与经典毒株VR-2332核苷酸同源性仅为66.7%，与高致病变异株SD、JXA1的核苷酸同源性高达98.8%，GP5基因在个别碱基上也存在变异，由此表明该毒株为高致病性蓝耳病变异株。同时将该病料接种于Marc-145细胞，可观察到典型的细胞病变(CPE)，经Reed-Muench计算该分离株的病毒滴度为10^−5.67 TCID₅₀/0.1mL。该毒株的分离鉴定，为进行猪繁殖与呼吸综合征流行病学的调查研究提供了依据。

Abstract: The visceral organs were collected from swines at a farm in ChongQing. Once the paghogen was idetified as the porcine reproductive and respiratory syndrome virus via RT-PCR identification, we used reverse transcription to make cDNA. Both NSP2 and GP5 gene were amplified by PCR, and then they were sequenced. The NSP2 sequence analysis indicated that homology between CQ and classical VR-2332 strain was 66.7%, while it was as high as 98.8% compared with HP-PRRSV vari-ation SD and JXA1 in nucleotide. And the GP5 sequence analysis indicated that there were varia-tions in individual bases. It was suggested that the CQ strain was a HP-PRRSV variation. At the same time, the patho-material was inoculated in Marc-145 cells, and then the CPE appeared. The viral titer is 10^−5.67 TCID₅₀/0.1mL by Reed-Muench. The separation of CQ strain offers basis for ep-idemiology investigations of PRRSV.