【摘要】 以1日龄土鸡为对象，以免疫器官指数和血清免疫指标为指标，对照组(CT)饲喂基础日粮，其他组分别在基础日粮中添加0.1%(ET1组)、0.2%(ET2组)和0.4%(ET3组)的复合多糖饲料添加剂，试验周期为42 d，探讨复合多糖添加剂对土鸡免疫功能的影响.结果表明：在试验第一阶段(1～21 d)，与CT组相比，ET1、ET2、ET3组的胸腺指数、法氏囊指数均有提高，脾脏指数有所降低，但无显著性差异(P>0.05)；ET2、ET3组IgG、IgM 的含量均明显高于CT组(P<0.05)；ET1、ET2、ET3组的土鸡血清中IL-2、IL-12、TNF-α和IFN-γ含量有显著性提高(P<0.05).在试验第二阶段(22～42 d)，与CT组相比，土鸡免疫器官指数有了一定程度的上升.ET1、ET2、ET3组IgA、IgG含量差异明显(P<0.05)，IgM含量有一定程度的提高，但是差异不显著(P>0.05)；ET2、ET3组土鸡血清中IL-2含量显著提高(P<0.05)；ET1、ET2、ET3组的土鸡血清中IL-12、TNF-α含量显著提高(P<0.05)；ET3组的土鸡血清中IFN-γ含量显著提高(P<0.05).研究表明复合多糖添加剂可通过提高土鸡免疫器官指数、免疫球蛋白含量，促进细胞因子IL-2、IL-12、TNF-α、IFN-γ的分泌来提升土鸡的免疫功能.更多还原

【Abstract】 1-day-old free-range chickens were used as the research object.The immune organ index and the serum immune index were used as indicators.The control group (CT) was fed with the basic diet and the other groups were added with 0.1% (ET1 group),0.2% (ET2 group) and 0.4% (ET3 group) compound polysaccharide feed additive granules in the basic diet.The effect of compound polysaccharide additives on the immune function of free-range chickens was investigated.The test period was 42 days.The results showed that in the first phase of the trial (1-21 d),compared with the CT group,the thymus index and bursa of Fabricius index of the ET1,ET2,and ET3 groups increased and the spleen index decreased.However,there was no significant difference (P>0.05).The levels of IgG and IgM in the ET2,ET3 groups were significantly higher than those in the CT group (P<0.05).The content of IL-2,IL-12,TNF-α,TNF-α and IFN-γ in the ET1,ET2,ET3 groups increased significantly (P<0.05).In the second phase of the experiment (22-42 d),compared with the CT group,the immune organ index of free-range chickens increased to a certain extent.The levels of IgA and IgG in the ET1,ET2,and ET3 groups were significantly different (P<0.05).The IgM content increased to a certain extent,but the difference was not significant (P>0.05).The IL-2 content in the blood serum of the ET2 and ET3 groups increased significantly (P<0.05).The content of IL-12 and TNF-α in the serum of the ET1,ET2,and ET3 chickens increased significantly (P<0.05).Besides,the IFN-γ content in the serum of the ET3 chickens also increased significantly (P<0.05)).The results revealed that the compound polysaccharide additive improved the immune performance of free-range chickens by both improving the immune organ index and immunoglobulin content of free-range chickens and promoting the secretion of cytokines IL-2,IL-12,TNF-α,and IFN-γ.更多还原