【作者】 贾泽颖；

【导师】 赵立红；

【作者基本信息】 中国农业大学 ， 预防兽医学， 2004， 硕士

【摘要】 禽流感（AI）是一种严重危害家禽生产的传染病。高致病性毒株，如AIV-H5N1对鸡的致死率高达100％。目前，国内、外对AIV-H5通常采取感染鸡群全部扑杀，周边地区鸡群紧急接种疫苗形成免疫保护带等措施控制其流行。然而，疫苗接种14天后才能达到有效的抗体滴度，不能及时形成有效保护。因此，研究在疫苗免疫建立之前对AIV-H5易感鸡群有保护作用的方法，对控制AIV-H5的扩散有一定意义。本试验通过制备高效价AIV-H5卵黄免疫球蛋白（AIV-H5 IgY），探讨AIV-H5 IgY对鸡的被动免疫保护效果。 本研究采用分离毒株A/chicken/Hebei.china/2001（H5N1），制成高效价AIV-H5N1灭活油苗，经5次大剂量强化免疫普通蛋鸡，可使其AIV-H5 IgY效价高达2¹⁰～2⁸，维持5个月以上。采用乙酸-乙酸钠沉降脱脂法和固体硫酸铵盐析法，从高抗体滴度卵黄液中提取AIV-H5 Igy，并用0.05％甲醛在4℃条件下作用24小时，对纯化的AIV-H5 IgY进行灭活。攻毒保护试验表明，在攻毒前或同时注射AIV-H5 IgY(HI效价为2¹⁰)，第一天为1.5ml，以后为1ml／天，继续使用2天，对攻毒雏鸡的保护率可达100％，而攻毒对照雏鸡100％死亡。与灭活油苗配合使用不能增加对攻毒雏鸡的保护率，但与抗病毒药-金刚烷胺配合使用可在一定程度上提高对攻毒雏鸡的保护率。更多还原

【Abstract】 Highly pathogenic avian influenza (HPAI) is a serious and often fatal infection in domestic poultry. An epidemic can cause significant economic damage. The avian influenza H5N1 virus (AIV-H5N1) subtype has boon associated with HPAI phenotype. In China, the eradication of HPAI is that all of the infected poultry are slaughtered and the poultry around are instantly vaccinated. But the antibody against AIV-H5N1 ascends to the effective titer only at postinoculation 14 days. This paper reports the preparation of egg yolk immunoglobulins against AIV-H5N1 (AIV-H5 IgY) and the effectiveness of AIV-H5 IgY in blocking chicken infection with AIV-H5N1.The laying hens were highly immunised by inoculating 5 times with the killed AIV-H5N1 (A/chicken/ Hebei.China/2001) vaccine. AIV-H5 IgY HI titres reach to 210~28 and last more 5 months.The AIV-H5 IgY was purificated by degreasing with acetic acid-sodium acetate buffer and salting out with solid ammonium sulfate. The inactivation with 0.05% of formalin under 4# for 24 hours did not effect the protective efficiency of AIV-H5 IgY against AIV-H5N1. The protective rate could be 100% by injecting AIV-H5 IgY (HI titre 210, with 1.5ml firstday, 1ml /day for 2days ) 0, 24 hours before H5N1 virus challenge, but the challenged chickens without AIV-H5 IgY injection were wholly dead.The protective efficiency of AIV-H5 IgY is not obviously improved by combination with the killed vaccine, but enhanced in some extent with amantadine.更多还原