蛹虫草基质多糖对鸡传染性支气管炎灭活疫苗的免疫佐剂作用

Adjuvanticity of Cordyceps militaris stroma Polysaccharides in Inactivated Vaccine to Avian Infectious Bronchitis

以蛹虫草基质多糖为免疫佐剂,将其混入传染性支气管炎灭活疫苗,从而探讨其对肉仔鸡的免疫功能影响。选用150只1日龄黄羽肉鸡,随机分成5组。免疫后21 d(35日龄)采用IBV M41株病毒液进行点眼、滴鼻攻毒。通过测定每组的鸡淋巴细胞(PBMC)增殖情况、鸡血清抗体效价、IBV强毒株攻毒保护及组织病理学变化。结果表明,蛹虫草基质多糖中剂量佐剂组的鸡淋巴细胞(PBMC)增殖指数、鸡血清抗体效价水平有着显著提高(P<0.05),在IBV M41株攻毒试验中,蛹虫草基质多糖中剂量佐剂组可以显著减轻病毒感染肉仔鸡临床症状,肺和肾无组织病理学变化,免疫保护率达到96.7%。表明以蛹虫草基质多糖佐剂能够提高肉仔鸡对传染性支气管炎的免疫力。

It aimed to use Cordyceps militaris stroma polysaccharides as adjuvants that mix with inactivated vaccine to infectiousbronchitis,and to investigate its effects on the immune functions of broilers. Total 150 1-day Huangyu broilers were selected and randomlydivided into 5 groups. Then the broilers of 21 d after immunized（35-day）were infected with Mass 41 infectious bronchitis virus（IBV M41）strain by the ocular-nasal route. The proliferation of peripheral blood mononuclear cells（PBMC）,serum antibody titer,the protection of IBVvirulent strain,and histopathological changes in each group were evaluated respectively by MTT method and hemagglutination inhibition assay.The results showed that proliferation index of PBMC and serum antibody titer in the broilers with dosage C. militaris stroma polysaccharidesas adjuvants significantly raised（P〈0.05）. Following challenge test with IBV M41 strain,broilers inoculated with C. militaris stromapolysaccharides showed significantly lighter clinical symptoms,there were no histopathological changes in lung and kidney,and immuneprotection reached 96.7%. This indicated that C. militaris stroma polysaccharides as adjuvants increased the immunity of broilers to infectiousbronchitis.