2株肉鸡源传染性法氏囊病病毒的分离鉴定  

Isolation and identification of two strains of infectious bursal disease virus from broiler

作　　者：刘文健 刘吉文 覃依依 戴金凤 闫丽萍 LIU Wenjian;LIU Jiwen;QIN Yiyi;DAI Jinfeng;YAN Liping(College of Veterinary Medicine,Nanjing Agricultural University,Nanjing 210095,China;Guangxi Lichengdong Biological Co.,Ltd.,Nanning 530100,China)

机构地区：[1]南京农业大学动物医学院,江苏南京210095 [2]广西丽诚东生物股份有限公司,广西南宁530100

出　　处：《畜牧与兽医》2024年第5期73-81,共9页Animal Husbandry & Veterinary Medicine

基　　金：国家自然科学基金面上项目(32272994)。

摘　　要：为了解传染性法氏囊病病毒(infectious bursal disease virus,IBDV)的流行情况,监测其优势流行毒株的基因型变化,对疑似IBDV感染的临床病料进行检测,通过有限稀释法对IBDV毒株进行分离纯化,对分离毒株进行遗传进化分析和致病力分析。结果显示:从阳性病料中成功分离得到2株纯净的IBDV毒株;遗传进化分析结果显示,HN-2022-1株属于经典株,其VP2蛋白高变区具备经典毒株分子标志;AH-2022-1株属于HLJ0504样超强毒株,存在节段重配现象,其VP2蛋白高变区除具备超强毒株分子标志外,还具备经典株、早期变异株分子标志。此外,AH-2022-1株在VP2蛋白第一亲水区还发现了3处从未报道过的氨基酸突变,这导致第一亲水区的亲水性下降,可能引起该毒株发生毒力变化。致病力分析结果显示,2株IBDV均可引起严重的法氏囊萎缩,发病率100%,但仅AH-2022-1株可引起20%死亡率,与HLJ0504样株报道的60%~80%死亡率并不一致。提示:IBDV处于不断进化中,IBDV经典毒株仍在我国持续流行,研究结果为我国IBDV感染的防控提供了一定参考。In order to conduct an epidemiological investigation of infectious bursal disease virus(IBDV)and to monitor changes in its dom-inant epidemic genotypes,clinical material suspected to be infected with IBDV was tested in this study and the IBDV strains were then isola-ted by finite dilution method.Subsequently,the genetic evolution analysis and pathogenicity analysis were carried out.The results showed that two IBDV strains were successfully isolated from the positive disease materials in this study.The genetic evolution results showed that the HN-2022-1 strain belonged to the classic strain,and its VP2 protein hypervariable region had the molecular markers of the classic strain.The AH-2022-1 strain belonged to the HLJ0504-like very virulent strains,and there was a phenomenon of segmental recombination.It is worth noting that the VP2 protein hypervariable region of AH-2022-1 strain not only had the molecular markers of very virulent strains,but also had the molecular markers of classic strains and variant strains.In addition,we also found three never-reported amino acid mutations in the first hydrophilic region of the VP2 protein of the AH-2022-1 strain,which led to a decrease in the hydrophilicity of the first hydrophilic region of the VP2 protein.This mmight cause changes in the virulence.The pathogenicity analysis results showed that the above two IBDV strains could cause severe cystic atrophy with an incidence rate of 100%,but only the AH-2022-1 strain could cause 20%mortality rate,which was not consistent with the 60%-80%mortality rate caused by the HLJ0504 very virulent strain.The successful separation of the above two IBDV strains and the results of the pathogenicity analysis suggested that IBDV was still in continuous evolution,and the classic strain of IBDV continued to be epidemic in China.This study provided reference for the prevention and control of IBDV in China.

关 键 词：传染性法氏囊病病毒 遗传进化分析 致病性分析 

分 类 号：S825[农业科学—畜牧学]