Giambrone J J, Closser J
Poultry Science Department, Auburn University, Alabama 36849-5416.
Avian Dis. 1990 Jan-Mar;34(1):114-9.
Two experiments were conducted to determine the effect of breeder vaccination program and maternal antibody on the efficacy of Newcastle disease immunization of 1-day-old chicks. Experimental protocol was the same for both. In the first experiment, broilers were from breeders that were 32 weeks old, and in the second experiment, broilers were from breeders 50 weeks old. Breeders received three live Newcastle disease virus (NDV) vaccines and either a killed vaccine at 18 weeks or continual live boosting at 60-to-70-day intervals through lay. Broilers were vaccinated at 1 day of age with a commercial coarse-spray machine; they were bled, sera were examined for antibody against NDV, and broilers were challenged with virulent NDV at 2, 4, and 6 weeks of age. In the first experiment, maternal antibody was higher in chicks from the younger breeders given the inactivated vaccine, and in the second experiment maternal antibody was higher in chicks from older breeders given continual live vaccines. Higher antibody in 1-day-old broilers resulted in fewer vaccine-induced reactions, less vaccine virus shed, and decreased duration of vaccine-induced immunity from coarse-spray vaccination.
进行了两项试验，以确定种鸡疫苗接种程序和母源抗体对1日龄雏鸡新城疫免疫效果的影响。两项试验的实验方案相同。在第一项试验中，肉鸡来自32周龄的种鸡；在第二项试验中，肉鸡来自50周龄的种鸡。种鸡接种了三种新城疫病毒（NDV）活疫苗，18周龄时接种了一种灭活疫苗，或在产蛋期间每隔60至70天持续接种活疫苗加强免疫。肉鸡在1日龄时使用商用粗喷雾器进行接种；对其采血，检测血清中抗新城疫病毒抗体，并在2、4和6周龄时用强毒新城疫病毒对肉鸡进行攻毒。在第一项试验中，接种灭活疫苗的年轻种鸡所产雏鸡的母源抗体较高；在第二项试验中，接种持续活疫苗的老龄种鸡所产雏鸡的母源抗体较高。1日龄肉鸡中较高的抗体水平导致疫苗诱导的反应减少、疫苗病毒排出量减少，以及粗喷雾接种疫苗诱导的免疫持续时间缩短。
