中文摘要：

为充分了解10多年来在生产中普遍使用的H9N2亚型禽流感（AI）灭活疫苗（F株）对鸡群的免疫保护效果，本研究以F株灭活疫苗分别接种SPF鸡和罗曼鸡，通过检测其抗体水平．分析比较抗体消长规律；同时FA2009-2010年间从免疫鸡群中分离到的9株H9N2亚型AIV为素材，通过F株灭活苗免疫攻击试验，来评价该疫苗对上述9株分离株体内感染的免疫保护效果。结果显示：F株灭活疫苗免疫SPF鸡和罗曼鸡3周后，产生的HI抗体效价均在7log2以上，且持续时间长，SPF鸡达15周，罗曼鸡在11周以上。SPF鸡免疫群用F9株、L9株、s9株和D9株和F株攻击7d后，对鸡的咽喉和泄殖腔排毒有100％的抑制作用，用其它5株（F119、W9、YD、M和D119）攻击后的抑制作用为90%；罗曼鸡免疫群用L9株、F9株、S9株、D9株、w9株和F株攻击7d后，对鸡咽喉和泄殖腔排毒有100％的抑制作用，用其它4株（F119株、YD株、M株和D119株）攻击后的抑制作用为90％；未接种疫苗的对照组鸡攻击7d后排毒率均为10／10。

英文摘要：

In order to observe the protective efficacy of widely-used inactivated H9N2 subtype avian influenza vaccine against,F strain inactivated vaccine was inoculated SPF chickens and Lohhman chickens respectively to analysis and compare the antibody level. 9 strains of H9N2 subtype avian influenza virus （AIV）were isolated from immunized chickens during 2009 to 2010 and the chickens were challenged with F strain vaccine to evaluate the effect of intercross immunization of H9N2 subtype vaccine （F strain） to the 9 isolates. The results showed that the antibody titer of F stain were all above 7 log2 after 3 weeks and the last time of antibody in SPF chickens and in Lohhman chickens was 15 weeks and 11 weeks respectively. The inhibition rates to virus shedding in SPF chickens＇ larynx and cloaca with F9,L9, S9,D9 and F strains challenged were all 100% for 7 days post challenge while those with F119,W9,YD,M and D119 were all 90%. The inhibition rates to virus shedding in Lohhman chickens＇ larynx and cloaca with Lg,F9,S9,D9,W9 and F strains challenge were all 100% for 7 days post challenge while those with Eltg,YD,M and Dll9 were all 90%. The rates of virus shedding in the control group chickens＇ larynx and cloaca were 10/10 for 7 days post challenge.