南方农业学报2023，Vol.54Issue(12)：3754-3762,9.DOI:10.3969/j.issn.2095-1191.2023.12.030
2021-2022年湖南省PRRSV流行病学调查及基因组特征分析
Epidemiological survey and genomic characteristics of PRRSV in Hunan during 2021-2022
摘要
Abstract
[Objective]To investigate the epidemiological characteristics and genotype proportion of porcine reproduc-tive and respiratory syndrome virus(PRRSV)in Hunan Province,which will provide reference for the prevention and control of PRRS in Hunan province.[Method]1184 tissue samples of pigs suspected of PRRSV infection were collected from 396 pig farms in Hunan Province from 2021 to 2022,and the positive rates of different genotypes were determined by fluorescence quantitative RT-PCR,and the PRRSV infection rates in different regions and seasons were counted.The ORF5 sequences of some positive samples were amplified by RT-PCR,and their sequence homology and genetic features were analyzed.Furthermore,the supernatant of some PRRSV-positive sample was incubated with Marc-145 cells for viral isolation,and the complete genomes of PRRSV strains were amplified using the Illumina technology for genetic evolution analysis,the SimPlot software was employed to identify the potential recombinant events occurred in the viral genome.[Result]167 tissue samples(14.1%)were PRRSV-positive,the positive rate of PRRSV in different regions and seasons were 0.0%～46.4%and 6.95%～19.67%,respectively.Moreover,the proportions of highly pathogenic PRRSV(HP-PRRSV),classical PRRSV and NADC30-like strains were 43.11%,15.57%,and 41.32%,respectively.A total of 21 complete ORF5 gene sequences(600 bp～603 bp)were obtained in this study,the homology analysis showed that 7 strains had the highest homology(92.1%～98.9%)with the reference HP-PRRSV strains;13 strains showed the highest amino acid sequence identities(91.3%～93.4%)with the reference NADC30-like strains;only one strain were genetically identified with the classical PRRSV strains,with the sequence identities of 98.6%～99.1%.The amino acid sequence align-ment analysis showed that the amino acid sequence variation rate of different PRRSV GP5 remained high,and the GP5 hypervariable regions of two NADC30-like strains had amino acid deletion,and the amino acid variation regions of some PRRSV strains were mainly located in the GP5 cell epitope region.Two PRRSV strains(named HuN-A and HuN-B)were isolated.The whole genome sequence analysis results showed that HuN-A strain belonged to the NADC30-like strain in subgenotype 1.5,and which was a recombinant virus with NADC30 strain as the main parent and HP-PRRSV strain as the secondary parent;However,the HuN-B strain belongs to HP-PRRSV strain.[Conclusion]This study revealed the se-vere prevalence of PRRSV in pig populations in Hunan Province,where PRRSV strains were divided into several geno-types.Among which the NADC30 and HP-PRRSV strains are the dominant genotypes.Two PRRSV strains were success-fully isolated here,the HuN-A strain was recombinant from the NADC30-like strain and the HP-PRRSV like strain(JXA1),while the HuN-B strain might be derived from the JXA1 attenuated vaccine strain,owing to the virulence re-gression.关键词
猪繁殖与呼吸综合征病毒(PRRSV)/流行病学调查/ORF5基因/重组分析/湖南省Key words
porcine reproductive and respiratory syndrome virus(PRRSV)/epidemiological investigation/ORF5 gene/virus isolation/recombination analysis/Hunan分类
农业科技引用本文复制引用
周宇骏,龙明英,孟芳,王文梅,邹玖零,廖淑玲,杜雅萍,禹思宇..2021-2022年湖南省PRRSV流行病学调查及基因组特征分析[J].南方农业学报,2023,54(12):3754-3762,9.基金项目
湖南省自然科学基金—科教联合项目(2021JJ60091) Hunan Natural Science Foundation Science and Education Joint Project(2021JJ60091) （2021JJ60091）
