黄芪多糖对鸡免疫禽传染性支气管炎弱毒疫苗免疫效果的影响

Effect of Astragalus polysaccharide on immune effect of attenuated avian infectious bronchitis vaccine in chickens

试验探究黄芪多糖(APS)对禽传染性支气管炎弱毒疫苗的免疫调节作用,以期发掘黄芪多糖用作疫苗佐剂的应用潜力。将120只14日龄蛋鸡随机分为3组,每组4个重复,每个重复10只蛋鸡,分别设置为APS+H120联合免疫组、H120疫苗组以及PBS阴性对照组。各组蛋鸡共进行3次免疫,每次间隔2周,每次鼻腔接种100μL/只。最后一次免疫14 d后经鼻腔攻毒禽传染性支气管炎病毒M41株,观察鸡的临床症状,检测肺脏和肝脏载毒量。结果显示,与H120疫苗组相比,APS+H120疫苗联合免疫能够诱导14日龄蛋鸡产生传染性支气管炎病毒(IBV)特异性免疫球蛋白G(IgG)和分泌型免疫球蛋白A(sIgA),有效保护蛋鸡抵抗同种异源毒株的攻击,蛋鸡存活率为100%。攻毒后APS+H120组蛋鸡未出现禽传染性支气管炎典型临床症状,蛋鸡生产性能未受到影响。研究表明,APS对禽传染性支气管炎H120弱毒疫苗的免疫效果具有促进作用。

The experiment investigated the immunomodulatory effects of APS on the avian infectious bronchitis attenuated vaccine,aiming to explore the potential application of APS as a vaccine adjuvant.A total of 120 fourteen-day-old chickens were randomly divided into three groups with four replicates per group and one chickens per replicate,designated as the APS+H120 co-immunization group,the H120 vaccine group,and the PBS negative control group.All groups of chickens were immunized three times at two-week intervals,with each nasal inoculation consisting of 100μL per chicken.Fourteen days after the final immunization,the chickens were intranasally challenged with the infectious bronchitis virus strain M41.The clinical symptoms of chickens were observed,and the amount of lung and liver virus was detected.The results showed that compared with the H120 vaccine group,the APS+H120 vaccine combined immunization can induce the production of IBV specific IgG and sIgA in 14-day-old chickens,effectively protecting them against the attack of allogenic strains,and the survival rate of laying hens was 100%.The APS+H120 group did not show the typical clinical symptoms of avian infectious bronchitis,and the production performance of laying hens was not affected.The study indicates that APS has a promoting effect on the immune response of chickens to the infectious bronchitis H120 attenuated vaccine.