Isolation and Identification of a Novel Mutated Strain of Infectious Bursal Disease Virus in Spotted Chicken
In recent years,a novel variant of chicken infectious bursal disease virus has been widely prevalent in China,mainly occurring in broiler chickens.It has the characteristics of weak pathogenicity and strong concealment,but it can cause severe atrophy of the bursa of Fabricius.This study collected the atrophic bursa of Fabricius from spotted chickens in Jining area,Shandong Province,to isolate the virus by SPF chicken embryos.The virus was identified through RT-PCR detection and injected to SPF chickens for pathogenicity testing,and then its main antigen gene VP2 was analyzed for evolution.It was found that the strain could kill chicken embryos.Sequencing comparison and evolutionary tree analysis of gene VP2 revealed a close evolutionary relationship with the gene sequences of recent novel variants,with homology ranging from 96.1％to 99.2％.On the 7th day of artificial infection in SPF chickens,there was a significant atrophy of the bursa of Fabricius,and on the 14th day,the atrophy was more pronounced,with a significantly smaller bursa to body ratio than the control group(P＜0.01).The JN22 strain of infectious bursal disease virus isolated in this study belongs to a novel mutant strain,which can cause significant atrophy of the bursal disease in SPF chickens.
Infectious bursal disease virus in chickensnovel variant strainspotted chickenatrophy of the bursa of Fabricius
国家科技期刊平台
NSTL
万方数据
维普
