一株鸡源H9N2亚型禽流感病毒的致病性及其HA基因遗传进化分析

摘要

为了解H9N2亚型禽流感病毒在新疆蛋鸡养殖场的致病性及遗传进化特点,对一株分离自蛋鸡的禽流感病毒A/Chicken/Xinjiang/01/2010 (H9N2)进行了致病性及遗传进化分析.结果显示,分离株的MDT为92 h,ICPI指数为1.125,IVPI指数为0.14,HA裂解位点处氨基酸序列为335RSSRGLF342,这些特征均证实该分离株为低致病性AIV.HA基因遗传进化分析表明,该分离株在系统进化树上与A/swine/XJWLMQ/7/09(H9N2)及3株野生鸟类新疆分离株的亲缘关系最为接近,该分离株HA基因属于欧亚谱系的A/chicken/Beijing/94(H9N2)和A/chicken/Hongkong/G9/97(H9N2)的一个分支.%For understanding the pathogenicity and phylogenetic characteristics of avian influenza virus which isolated from laying hen in a egg chicken plant of Xinjiang,the pathogenicity and phylogenetic analysis of A/Chicken/Xinjiang/01/2010 (H9N2) were studied.The results indicated that the MDT,ICPI and IVPI of the isolated strain were 92h,1.125 and 0.14,respectively.The cleavage site of HA was 335RSSRGLF342.All of the above indicated that the isolated strain was LPAIV.Phylogenetic analysis of HA gene showed that the isolated strain has close relationship with A/swine/XJWLMQ/7/09(H9N2) and other three AIV which isolated from wild bird in Xinjiang.The isolated strain belongs to the branch of A/chicken/Beijing/94(H9N2) and A/chicken/Hongkong /G9/97(H9N2).