Abstract: In this research, samples of lung and lymph node of dead pigs with suspicious highly pathogenic porcine reproductive and respiratory syndrome (HPPRRS) were collected from a pig farm. The genome of PRRSV with Nsp2 segment deletion was detected from these samples by RT-PCR. The samples, which were determined to be PRRSV positive by RT-PCR, were infected to the Marc-145 cells and cultured for 72 to 96 h until the monolayer cells showed obvious CPE. The virus was harvested and named as HPPRRSV-GD07b. According to the PRRSV sequences published on GenBank, a pair of specific primers was designed and used for RT-PCR amplification gene Nsp2 of PRRSV GD07b isolate. The length of product was 200 bp, which was 90 bp shorter than that of the VR-2332 strain, a classic PRRSV. After purification, the amplification product was sequenced. The sequence was compared with those of Nsp2 gene of other 19 strains PRRSV. The homology of Nsp2 gene of this isolate and 4 classic strains like CH-1a was relatively low to be 60.5% to 81.6%, while the homology between this isolate and other 14 variant strain was 90.6% to 98.9%.

Key words: highly pathogenic porcine reproductive and respiratory syndrome virus; isolation; identification; Nsp2 gene