江苏及周边地区猪流行性腹泻病毒的检测及其ORF3基因序列分析

Dectection of PEDV in Jiangsu and its surrounding areas and sequence analysis of the viral ORF3 gene

根据江苏省及周边地区猪场2014年出现的临床腹泻病例,对发病猪送检病料进行了猪流行性腹泻病病毒（PEDV）、猪传染性胃肠炎病毒（TGEV）、轮状病毒（RV）这3种重要病毒进行检测,同时分析PEDV的ORF3基因序列。结果显示：建立的三重RT-PCR检测方法,检测下限可达10^4拷贝/μL的混合质粒,特异性好,没有扩增出其他病毒。PEDV感染率高达36.3%,TGEV与RV的感染率均不足1%,此外还存在1例PEDV与TGEV混合感染的情况。对部分PEDV阳性病料的ORF3基因进行序列分析,发现核苷酸（氨基酸）的同源性为95.9%-100%（96.9%-100%）,且与疫苗毒株遗传关系较远。该结果明确了江苏及周边地区的仔猪病毒性腹泻病原,为该病的防控提供参考依据。

In this study,the infection rates of porcine epidemic diarrhea virus（ PEDV）,transmissible gastroenteritis virus（ TGEV） and rotavirus（ RV） in the samples obtained from pigs at different ages on pig farms in Jiangsu Province and its surrounding areas have been detected,and sequences of ORF3 gene of PEDV were also analyzed. An established triple RT-PCR assay was used with a detection limit of 10^4copies/μL without amplification of other viruses. The results were as follows： The infectious rate of PEDV was 36. 3%,and those of TGEV and RV were both lower than 1%. Furthermore,there was a sample of mixed infection of PEDV and TGEV. Analysis of diarrhea virus infection in pigs at different ages showed that viral diarrhea,especially PEDV,occurred in piglets and nursery pigs. Meanwhile,the ORF3 genes of some PEDV strains had nucleotide（ deduced amino acid） sequence homologies of 95. 9%-100%（ 96. 9%-100%）,having a loose genetic relationship with vaccine strains. This study clearly identified the pathogens of piglets＇ viral diarrhea in Jiangsu and its surrounding areas,providing a reference for future prevention and control of the disease.