Epidemiological investigation and sequence analysis of reproductive disorder and respiratory syndrome in pig farms in Shaanxi and Henan provinces
Porcine reproductive and respiratory syndrome(PRRS)is one of the major diseases affecting the global swine indus-try.PRRSV has the highest mutation rate among RNA viruses.In order to understand its molecular characteristics and genetic var-iation,252 suspected samples collected from pig farms in Shaanxi and Henan regions were analyzed for ORF5 gene and Nsp2 gene sequence comparison and genetic variation analysis using RT-PCR assay and bioinformatics software in this study.The re-sults showed that 39 out of 252 samples were positive,with a positive rate of 15.6%.Sequencing of the 39 positive samples yiel-ded ten Nsp2 gene-positive samples and five ORF5 gene-positive samples.The nucleotide sequence homology between the five PRRSV ORF5 gene strains and the ORF5 gene of the 26 PRRSV reference strains in GenBank ranged from 79.7%to 99.7%,and that between the ten PRRSV strains and the ORF5 gene ranged from 38.7%to 99.7%,and that between the ten PRRSV strains and the ORF5 gene ranged from 38.7%to 99.7%.Nucleotide sequence homology ranged from 38.2%to 92.2%;the ho-mology of the nucleotide sequences of the ORF5 genes of the five strains ranged from 85.1%to 99.8%,among which the five strains with the ORF5 genes of strains GP5-5,GP5-7,and GP5-10 were strains of the PRRSV-2 lineage 1,and strains 99L and 100L were strains of the PRRSV-2 lineage 5,which were identical to representative the Nsp2 gene of the 10 PRRSV strains is a strain of PRRSV-2 lineage 1,99L and 100L strains are strains of PRRSV-2 lineage 5,which are closest to the representative strains NADC30 and VR-2332,respectively;the Nsp2 gene of the 10 PRRSV strains is a strain of PRRSV-2 lineage 1,which is the closest to the representative strain NADC30;the GP5 and NSP proteins are mutated to varying degrees,which indicates that the PRRSV strains are frequently mutated,so we need to monitor the dynamics of the PRRSV strains and explore their patterns of genetic mutation in real-time.Therefore,real-time monitoring of the genetic variation of PRRSV strains and exploring their genetic variation patterns can provide scientific references for the prevention and control of epidemics.
porcine reproductive and respiratory syndromeORF5Sequence analysisNsp2Genetic evolutionary analysis
万方数据
维普
