作　　者： ; ; ; ; ; ;

机构地区： 佛山科学技术学院生命科学学院

出　　处： 《安徽农业科学》 2007年第18期5435-5438,共4页

摘　　要： 对经过H5N1油苗免疫的50日龄番鸭,按HI抗体水平分组后,进行人工接种HPAIV,通过试验鸭的临床症状、病理变化和排毒情况综合判断HI抗体水平与保护力之间的关系。结果表明,HI抗体水平在5.0log2以下时,番鸭群可感染HPAIV,出现临床症状,表现不同程度的病理变化,并有排毒现象。抗体水平达到3.0log2-5.0log2的免疫番鸭群已具有一定的抵抗力,可以延缓发病时间,降低发病程度。随抗体水平的升高,发病与排毒的程度有所下降。当抗体水平达6.0log2及以上时,番鸭对人工接种HPAIV具有完全抵抗能力,不排毒。因此,番鸭对H5N1亚型HPAIV具完全抵抗力的HI抗体水平的临界保护滴度为6.0log2。 50-day-old Muscovy, ducks were grouped according to the different antibody levels to AIV H5N1 inoculated with corresponding inactivated vaccine ,and each group was intramuscularly challenged with virulent AIV isolated from duck.The clinical signs and gross pathogenic changes were recorded at different timetable after Muscovy duck challenged with AIV. The laryngotracheal and cloacal swabs as well as partial internal organs were inoculated in 11- day-old chicken embryos intra-allantoid cavity for AIV isolation.The results showed that antibody levels detected by HI test less than 5.0log2 could not resist the challenge of virulent AIV HSN1 subtype,and clinical signs and different degrees of gross pathogenic changes were observed,furthermore,the shedding viruses were verified.If antibody levels detected by HI test was between 3.0log2 and 5.0log2,the degrees of latent period for showing symptoms,the pathogenic signs were lessened, and the partial resistant capability was found. While the antibody levels detected by HI test were more than 6.0log2, no clinical signs,gross pathogenic changes and shedding vires were detected.So far 6.0log2 could be regarded as the critical titer for H5 subtype AIV.Muscovy duck could resist virulent AIV challenge well when their attained to more than 6.0log2 by HI test.

关 键 词： 番鸭 禽流感 抗体水平 保护力

领　　域： [农业科学] [农业科学]