1株野鸭源H6N2亚型AIV对SPF鸭的致病性

Pathogenicity of SPF ducks infected with the low-pathogenic avian influenza virus H6N2 subtype isolated from wild birds

本研究选取2周龄SPF鸭(绍兴麻鸭)自天然孔感染1株野鸭源H6N2亚型LPAIV,评价其对幼龄鸭的致病性。结果显示,试验感染鸭临床症状较轻微,病毒在鸭消化道复制能力较呼吸道内更强,且具有水平传播的能力。仅能在盲肠扁桃体和法氏囊2个组织器官中检测到病毒,但可对法氏囊等多个组织器官造成不同程度的损伤。此外感染鸭可产生HI抗体,并在第21天达到高峰。结果表明,该株H6N2亚型LPAIV对幼龄鸭的致病力较低,在AIV病毒传播中幼龄鸭起到了一定作用,为研究H6N2亚型LPAIV的致病机制及AIV发病机理提供了理论数据。

Two-week-old SPF duck（Shaoxing sheldrake） was infected by an isolates of LPAIV H6N2 subtype from wild duck by natural route infection to study the pathogenicity to duckling of the isolate. The results showed that virus can propagate more effectively in respiratory tract than digestive tract. Despite of mild clinical symptoms, virus has stronger ability on horizontal trans- mission. This virus can propagate only in caecum tonsil and bursa of fabricius, while the patholog- ical damage occurred in some tissues and organs in varying degrees. Besides, the antibody against HI can be detected after infection,and the antibody level reached its peak at 21 days after infec- tion. The results indicated that isolates of LPAIV H6N2 subtype is low pathogenic to the duck- ling,which plays a key role during AIV spread It lays a fundation for further research on pathogenic mechanism.