动物医学进展2018，Vol.39Issue(3)：24-29,6.
猪流产胎儿中猪繁殖与呼吸综合征病毒的检测及GP5抗原分析
Detection of Porcine Reproductive and Respiratory Syndrome Virus in Aborted Fetus from Sows and Antigen Analysis of GP5
摘要
Abstract
There were some sows in late gestation which produced dead fetus in November 2016,at a large scale pig farm in Henan.However,all of pigs in the pig farm were inoculated with the highly pathogenic PRRSV attenuated vaccine four times in a year.In order to clarify the agent of the disease,lungs were col-lected from stillbirth for RT-PCR amplification of NSP2 gene fragment distinguishing the highly pathogen-ic and classical strains of PRRSV according to the fragment size and whole ORF5 genes.The results of RT-PCR showed that the NSP2 fragment of the detected PRRSV strain is about 418 bp,indicating that the de-tected strain is the highly pathogenic PRRSV strain;that the size of the full-length ORF5 gene amplifica-tion was consistent with the expected length.To explore the cause of the failure of PRRSV attenuated vac-cine immunization,phylogenetic trees were constructed using DNA Star by sequences of 1 8 different PRRSV ORF5 genes;at the same time,the deduced amino acid sequences between the detected strain and the other 1 7 PRRSV strains were analysed and compared.Sequence analysis of ORF5 genes showed that the detected PRRSV strain shares the highest homology with the FJYR isolate (97.2%)from Fujian,China, and the TJbd14-2 isolate(97.0%)from Henan,China in 2015;87.7% with America classic strain VR-2332;respectively 62.8% and 62.6% with Europe strain Lelystad virus and NMEU09-1.Analysis of the de-duced amino acid sequences according to ORF5 genes between the detected PRRSV strain and nine highly pathogenic PRRSV strains showed that 1 3 amino acid positions in the detected PRRSV strain were muta-ted.Analysis of GP5 antigen index showed that compared with the other 9 highly pathogenic PRRSV strains,antigenicity between 30-40 amino acid positions,and 51-63 amino acid positions in GP5 of the detec-ted PRRSV strain significantly decreased.Therefore,we speculated antigenicity variation may cause the immune failure of the highly pathogenic attenuated vaccine.The etiology of the abortion of the pig farm is a highly pathogenic,variant PRRSV strain belonging to American type PRRSV.关键词
流产胎儿/猪繁殖与综合征病毒/反转录-聚合酶链反应/GP5抗原性分析Key words
aborted fetus/Porcine reproductive and respiratory syndrome virus/RT-PCR/antigen analysis of GP5分类
农业科技引用本文复制引用
蒋增海,赵攀登,邓同炜,陈益,徐耀辉..猪流产胎儿中猪繁殖与呼吸综合征病毒的检测及GP5抗原分析[J].动物医学进展,2018,39(3):24-29,6.基金项目
河南牧业经济学院预防兽医学重点学科建设项目(MXK2016102) （MXK2016102）
