Detection,Isolation And Identification Of Porcine Rotavirus Infection In Some Areas Of China From2015 To 2016

Porcine rotavirus disease(Po RV)is an acute gastroenteritis infectious disease characterized by diarrhea,anorexia,vomiting and dehydration caused by porcine rotavirus.Porcine rotavirus is one of the major pathogens causing severe diarrhea in piglets worldwide,which causes huge economic losses to the global pig industry.Porcine rotavirus infection is characterized by short incubation period,strong infectivity,wide epidemic range and high incidence.The disease is aggravated by mixed infection with other viruses and bacteria,resulting in a high mortality rate,which seriously restricts the healthy development of pig industry in China.In order to understand the prevalence of porcine group A rotavirus(GARV),porcine group B rotavirus(GBRV),and porcine group C rotavirus(GCRV)in some areas of China.From January2015 to December 2016,321 samples of suspected piglets' diarrhea disease and 42 healthy piglets' feces were detected and analyzed by nested RT-PCR method.The results showed that the total positive rate of GARV was 44.10%.GBRV was 2.75% and GCRV was 6.61%.The strongly positive diarrhea material was inoculated into Vero cells after treatment with trypsin,and then the virus was sub-cultured,and a virulent strain with obvious CPE lesions was isolated.and then the isolated strain was identified.The virus was identified as porcine rotavirus named HJ-2016,and the VP4,VP6 and VP7 genes of isolated strains were sequenced and sequenced.The results showed that the strain was porcine group A rotavirus,and the genotype was G5P[7]I5,The two-day-old piglets without breast milk were infected with the isolated GARV HJ-2016 strain.The tissue tropism of GARV to infected piglets was detected by SYBR Green I real-time fluorescence quantitative RT-PCR method in order to explore its pathogenicity.The results showed that the viral load of the porcine rotavirus was the highest in the lung and the ileum of the control group,reaching 104~105 copies/?L,and the intestinal tissue had obvious pathological changes,and the GARV HJ-2016 strain was pathogenic.In this study,the molecular prevalence of porcine group A rotavirus,porcine group B and group C were confirmed in some parts of China in 2015 to 2016,and a strain of porcine group A rotavirus HJ-2016 was isolated.The real-time fluorescence quantitative method of SYBR Green? was established.The pathogenicity and infection mechanism of HJ-2016 strain were preliminarily discussed,which provided a theoretical basis for the study of molecular biological characteristics,pathogenic mechanism,vaccine development and comprehensive prevention and control of porcine group a rotavirus in swine in China.