关键词: 广西；猪繁殖与呼吸综合征病毒；分离；鉴定；遗传进化

Abstract: Porcine Reproductive and Respiratory Syndrome（PRRS）is a major disease caused by the Porcine Reproductive and Respiratory Syndrome Virus（PRRSV）that poses a serious threat to the swine industry. This study aims to gain a preliminary understanding of the genetic variation and epidemiological characteristics of PRRSV in pig farms in the Guangxi region of China. In January 2026，tissue samples were collected from a pig suspected of being infected with PRRS at a farm in Pinggui District，Hezhou City，Guangxi Autonomous Region. The samples were tested for PRRSV，subjected to virus isolation and culture，examined for viral particle morphology，and amplified for the ORF5 gene sequence. The ORF5 amplification products were then sequenced and analyzed for genetic variation. PCR testing and sequencing confirmed that the tissue samples collected from the farm in Pinggui District，Guangxi，were PRRSV nucleic acid?positive；A PRRSV strain capable of inducing typical lesions in 763 cells（a Marc?145 derivative line）was isolated from the tissue samples；ORF5 sequence analysis revealed that this isolate belongs to the NADC30? like strain （American ? type strain）， showing the highest genetic homology （95.36% ） with the PRRSV GXHX20211106 strain，and its amino acid sequence showed the highest homology（91.0%）to the PRRSV?2 strain AP207（ALT01910）. Electron microscopy revealed that the viral particles were oval in shape，with a diameter of approximately 60 nm，which is essentially consistent with the morphology of PRRSV particles；the strain was named PG2026. This study successfully isolated a pathogenic NADC30?like PRRSV?2 strain from Pinggui District，Hezhou City，Guangxi. The findings provide reference data for studying the genetic variation trends of circulating PRRSV strains in the Guangxi region and for the scientific and rational use of vaccines.

Key words: Guangxi；Porcine reproductive and respiratory syndrome virus；Isolation；Identification；Genetic evolution