不同母源抗体水平雏鸡IBD免疫程序的探讨

STUDIES ON THE IMMUNIZATION PROGRAMME OF IBD VACCINES IN CHICKENS WITH DIFFERENT LEVELS OF MATERNAL ANTIBODIES AGAINST IBDV

采用酶联免疫吸附试验（ＥＬＩＳＡ）检测了１ｄ龄石岐杂雏鸡的ＩＢＤ母源抗体，根据不同母源抗体水平的高低，将１ｄ龄石岐杂雏鸡的ＩＢＤ母源抗体分为高、中、低３种水平．针对每个ＩＢＤ母源抗体水平的雏鸡设计了３种不同的ＩＢＤ双价苗的免疫程序．用ＥＬＩＳＡ检测免疫前后ＩＢＤ抗体的动态变化，并于２３ｄ龄时用ＩＢＤ强毒对雏鸡进行攻毒．结果说明，不同母源抗体的雏鸡，其ＩＢＤ的最佳免疫时机是不同的．作者建议使用ＩＢＤ双价苗免疫石岐杂雏鸡时，可根据１ｄ龄鸡群ＩＢＤ母源抗体的平均ＥＬＩＳＡ滴度，用公式“最佳接种日龄＝（抗体滴度－３４．６４）／２．８２＋１”预测最佳首免日龄．作者最后提出了一个控制石岐杂肉鸡ＩＢＤ流行的方法．

The maternal antibodies against infectious bursal diseaes virus (IBDV) were measured by enzyme linked immunosorbent assay (ELISA) in day old Shiqiza broilers,then the broilers were divided into three groups according to the levels of maternal antibodies and each group allocated three different immunization programmes. The antibodies against IBDV were also measured by ELISA before and after vaccinations. All the broilers were challenged with virulent IBDV strains at 23 days of age. The results showed that the optimal vaccination time was different for the broilers with different levels of maternal antibodies. The following formula “Optimum age for vaccination=(ELISA titre-34.64)/2.82+1” was suggested to predict the optimum age for first vaccination of IBDV vaccines. For the control of IBD in Shiqiza chickens,it was suggested that oil emulsion inactivated IBDV vaccines should not be used in parent broilers,while the progeny be vaccinated with live IBDV vaccines at the age of 1 day and by drinking water with IBDV vaccines at 8 and 15 days of age.