母源抗体对鸡新城疫疫苗免疫的影响

Influence of ND maternal antibody on the efficiency of ND vaccine in chickens

该试验旨在通过在不同日龄分别选用不同的疫苗组合 ,对有鸡新城疫母源抗体的雏鸡进行免疫 ,探讨不同疫苗组合克服母源抗体的效果。结果表明 :有 ND母源抗体的雏鸡用弱毒疫苗免疫后 ,母源抗体对弱毒疫苗免疫干扰较大 ,只有当 ND母源抗体降到较低水平 (小于 3log2 ,一般要到 1 5～ 2 0日龄后 )时 ,对弱毒疫苗免疫影响才非常小 ,方可产生较为可靠的免疫力 ;用ND弱毒疫苗 +油乳剂疫苗进行免疫 ,可有效地克服母源抗体的干扰 ,获得理想的免疫效果。但母源抗体对 ND油乳剂疫苗免疫的影响在日龄越小的雏鸡越明显 ,因此于 8～ 1 0日龄之后用 ND弱毒疫苗 +油乳剂疫苗进行免疫是最佳选择 。

This experiment's aim is to evaluate the influence of ND maternal antibody in chicken's immune effect to different kinds of ND vaccines at different ages by using HA and HI test.The results show that the maternal antibody has much more influence on chicken's immune effect to ND vaccine.When the maternal antibody reduce to a certain level(<3 log2,15～20 days later),the immune effect could be satisfied,especially by using the live vaccine and oil-emulsion vaccine at the same time.The ND maternal antibody has more distinet inpluence on immune eppect in younger chicken by using of oil-emalsion vaccine.The favorite age at which the chicken is vaccinated with oil-emulsion vaccine is elder than 8～10 dyas.This results provide a new theory for ND immune program.