Jian Yanyin, Lu Chun, Shi Yuan, Kong Xiangyu, Song Jun, Wang Jintao
College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, 163319, China.
BMC Vet Res. 2025 Apr 3;21(1):242. doi: 10.1186/s12917-025-04679-y.
Porcine reproductive and respiratory syndrome (PRRS) was first discovered in North America in 1987, and since then it has been spread widely all over the world. The prevalence of PRRS has caused significantly economic losses to pig industry in many countries.
Investigate the prevalence and genetic evolution of porcine reproductive and respiratory syndrome virus (PRRSV) in five provinces of northern China.
190 samples suspected of PRRS were collected from 28 pig farms in five provinces of northern China. The PRRSV ORF7 and ORF5 gene were detected by RT-PCR, and the ORF5 gene were sequenced for the homology and genetic evolution analysis.
The positive samples of ORF7 gene were 50, and its positive rate was 26.32%. The positive samples of ORF5 gene were 48, and its positive rate was 25.26%. The sequenced results of the ORF5 gene showed that 48 positive samples all belonged to PRRSV-2. Among them, 26 samples were NADC34-like strains, 17 samples were NADC30-like strains, and 5 samples were classical strains. The amino acid sequence analysis of PRRSV GP5 indicated that there was a deletion at the 37th amino acid in 4 NADC30-like strains. The amino acids of the transmembrane region 1 in all positive strains are relatively conserved, and multiple amino acid mutations were observed in the signal peptide, transmembrane region 2, and B cell epitope. The amino acid mutations were different in different strains and regions. The above results demonstrated that the complexity and diversity of PRRSV genetics.
The strains from lineage 1 became the dominant strains in five provinces of northern China in 2024. The positive rate of NADC34-like strains was the highest in Heilongjiang Province and the NADC30-like strains were the most prevalent in these regions. The genetic evolution of PRRSV presented a complex trend. This study provided the data support for understanding PRRSV variation and for PRRS prevention and control in five provinces of northern China.
猪繁殖与呼吸综合征（PRRS）于1987年在北美首次发现，此后在全球广泛传播。PRRS的流行给许多国家的养猪业造成了巨大的经济损失。
调查中国北方五省猪繁殖与呼吸综合征病毒（PRRSV）的流行情况及基因进化。
从中国北方五省的28个猪场采集190份疑似PRRS的样本。采用RT-PCR检测PRRSV的ORF7和ORF5基因，并对ORF5基因进行测序以进行同源性和基因进化分析。
ORF7基因阳性样本50份，阳性率为26.32%。ORF5基因阳性样本48份，阳性率为25.26%。ORF5基因测序结果显示，48份阳性样本均属于PRRSV-2。其中，26份样本为NADC34-like毒株，17份样本为NADC30-like毒株，5份样本为经典毒株。PRRSV GP5的氨基酸序列分析表明，4株NADC30-like毒株在第37位氨基酸处有缺失。所有阳性毒株跨膜区1的氨基酸相对保守，信号肽、跨膜区2和B细胞表位出现多个氨基酸突变。不同毒株和地区的氨基酸突变不同。上述结果表明PRRSV遗传具有复杂性和多样性。
1型毒株在2024年成为中国北方五省的优势毒株。黑龙江省NADC34-like毒株阳性率最高，NADC30-like毒株在这些地区最为流行。PRRSV的基因进化呈现复杂趋势。本研究为了解中国北方五省PRRSV变异情况及PRRS防控提供了数据支持。
