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

摘要： 猪繁殖与呼吸综合征（Porcine Reproductive and Respiratory Syndrome，PRRS）是由猪 繁殖与呼吸综合征病毒（Porcine Reproductive and Respiratory Syndrome Virus，PRRSV）引起的一 种严重危害养猪业的重要疫病。该研究旨在初步了解我国广西地区猪场中PRRSV的遗传变异 情况和流行特点。于2026年1月份采集广西自治区贺州市平桂区某养殖场1头疑似患PRRS猪 的组织病料，进行PRRSV检测、病毒分离培养、病毒粒子形态观察和ORF5 基因序列扩增，并对 ORF5 扩增产物进行测序和遗传变异特征分析。经PCR检测和测序确认从广西平桂区养殖场 采集的病料为PRRSV核酸阳性，从病料中分离到一株可在763细胞（Marc?145衍生细胞株）中 产生典型病变的PRRSV，ORF5 序列分析发现分离株属NADC30?like 毒株（美洲型毒株），与 PRRSV GXHX20211106毒株基因同源性最高（95.36%），氨基酸序列与PRRSV?2型毒株AP207 （ALT01910）同源性最高（91.0%）。电镜观察结果显示病毒粒子在电子显微镜下呈椭圆形，直径 约60 nm，与PRRSV病毒粒子形态基本一致，命名为PG2026。该试验成功从广西贺州市平桂区 分离出1株致病性NADC30?like PRRSV?2型毒株，为研究广西地区PRRSV流行毒株的遗传变异 趋势及疫苗的科学合理使用提供了参考数据。

关键词: 广西；猪繁殖与呼吸综合征病毒；分离；鉴定；遗传进化