中文摘要：

【目的】探讨鸭瘟弱毒苗诱导鸭局部黏膜和系统免疫中抗体发生的规律。【方法】将DPV弱毒苗Cha株经皮下、口服和滴鼻途径免疫20日龄樱桃谷鸭后60 d内定时随机剖杀5只鸭，采集血清、气管和消化道（食道、十二指肠、空肠和直肠）分泌液，应用间接ELISA检测抗DPV的IgA、IgM和IgG抗体滴度（以lg表示）。【结果】所有免疫鸭检测样品中均可检测到DPV特异性IgG、IgM和IgA抗体。血清中抗体滴度由高到低均为IgG、IgM和IgA，其中IgM检出时间最早，IgG存留时间最长。皮下免疫DPV弱毒苗可更早诱导鸭血清中生成特异性IgG，且抗体滴度最高；气管和消化道分泌液中抗体滴度由高到低均为IgA、IgM和IgG，其中IgA和IgM检出时间最早，IgA存留时间最长。口服和滴鼻途径免疫鸭消化道和气管分泌液中IgA滴度较皮下免疫鸭高。【结论】不同途径免疫鸭瘟弱毒疫苗均可迅速诱导免疫鸭体液免疫介导的黏膜免疫和系统免疫。以DPV特异性IgA为主要抗体的黏膜免疫在预防DPV强毒早期对鸭消化道和呼吸道等局部黏膜的感染中具有十分重要的作用，使DPV弱毒疫苗快速产生免疫保护的机制从黏膜免疫的角度得到一定程度解释。

英文摘要：

[Objective] To study the induction of IgA, IgG and IgM antibodies in local mucosal and systemic immunity of immunized ducklings induced by attenuated duck plague virus （DPV） vaccine strain. [Method] Twenty-day-old Cherry Valley duckling were vaccinated subcutaneously, orally and nasally with attenuated DPV Cha strain and five vaccinated ducklings were chosen for sampling at each of 10 sampling times between 1 and 60 days post immunization （PI）, and DPV-specific antibodies were detected in serum and the secretion from trachea and enteron （oesophagus, duodenum, jejunum and rectum） by indirect enzyme-linked immunosorbent assay （results were presents as the log10 geometric mean antibody titer ± SD）. [Result] This study indicated that DPV specific IgA, IgG and IgM antibodies could be detected in all tested samples of immunized ducklings. The antibody titers in serum from higher to lower titers was IgG. IgM and IgA, and IgM was produced firstly, while high titers IgG was detected for long-term. The IgG antibody titers in subcutaneously immunized ducklings was higher and detected earlier than those by oral or nasal administration. The antibody titers in secretion from respiratory and digestive tract from higher to lower titers was IgA, IgM and IgG. and specific IgA and IgM were detected earlier than IgG. The IgA antibody titers in orally and nasally immunized ducklings was higher than those by subcutaneous administration. [Conclusion] Data presented here indicated that the humoral immune responses of both systemic and mucosal immune system can be stimulated quickly with attenuated DPV vaccine strain by subcutaneous, oral or nasal administration. The DPV specific IgA antibody in respiratory and digestive tract fluids plays a predominant role in protection against virulent DPV infection in surface of local mucosa, which has explained the rapid induction of DPV specific immunity by live vaccine virus to some extent.