摘要
为了解传染性法氏囊病病毒(IBDV)广西流行株的遗传变异规律,本研究通过鸡胚绒毛尿囊膜(CAM)接种的方法对2006年～2007年间采集自广西各鸡场的疑似传染性法氏囊病(IBD)的病料进行病毒分离,设计针对VP2高变区(vVP2)的引物对分离物通过RT-PCR进行鉴定及序列分析。共分离出9个IBDV毒株,其ELD50在105/0.2mL～106.5/0.2mL之间。分离株vVP2序列通过具有分型意义的酶切位点和关键位点氨基酸分析,证实9个分离株均属于vvIBDV。同源性分析表明,9个分离株之间在核苷酸和氨基酸的同源性分别为97.2%～100%和95.2%～100%,与vvIBDV参考株同源性分别为93.8%～98.2%和92.4%～98.6%,而与常用疫苗株Bursine-2、B87(in),变异株GLS,经典毒株,中等偏强毒力株YL052的同源性仅有90%左右。遗传进化分析发现,分离株与vvIBDV参考株同处于1个大分支,与DV86和OKYM株的亲缘关系最近,与2000年～2005年间广西分离的vvIBDV株距离较远,它们之间形成了明显的分群。研究表明,近2年来广西仍然存在vvIBDV的流行。
Infectious bursal disease virus .（IBDV） were isolated by chicken embryo inoculation via chorio-allantoic membrane from affected bursa samples collected from Guangxi province of China during 2006 to 2007. Nine IBDV isolates were identified by RT-PCR and sequence analysis based on VP2 gene. Among the isolates high homology was found at 97.2 %-100 % nucleotide acid level （NAL） and 95.2 %-100 % at amino acids level （AAL）, respectively. In comparing with very virulent IBDV （wIBDV） reference strains, the homology percentage was 93.8 %-98.2 % at NAL and 92.4 %-98.6 %. at AAL. However, there was only 90 % identity at MAL to the vaccine strains Bursine-2 and 1387 （in）, variant strain GLS, intermediate-plus virulent strain YL052 and IBDV classical strain. Evolution analysis showed that the 9 isolates were classified into a large group of vvlBDV, which close to DV86 and OKYM strans, but far from the wlBDV strains isolated in Guangxi from 2000 to 2005. The results indicated that wlBDV is still epidemic in Guangxi in recent years.
出处
《中国预防兽医学报》
CAS
CSCD
北大核心
2009年第8期650-653,659,共5页
Chinese Journal of Preventive Veterinary Medicine
基金
广西自然科学基金项目(桂科自0728058)
广西科技攻关项目(2007A04024)
广西民族大学引进人才启动基金项目(0409025)
扬州大学江苏省动物预防医学重点实验室开放课题(K06012)
