Beard C W, Villegas P, Glisson J R
U.S. Department of Agriculture, Southeast Poultry Research Laboratory, Athens, Georgia 30605.
Avian Dis. 1993 Jan-Mar;37(1):222-5.
Groups of eight 1-day-old white rock chickens were vaccinated with either B-1 or VG/GA strain of Newcastle disease virus (NDV) by eyedrop instillation. Some of the chickens were vaccinated a second time at 17 days of age. Eight groups of chickens vaccinated either once or twice were challenged with the California 1083 strain of velogenic viscerotropic Newcastle disease virus (VVNDV) at 30 days of age by either intramuscular injection or eyedrop instillation. One group of unvaccinated control chickens was challenged by eyedrop instillation. All eight unvaccinated controls, two of the 16 B-1 vaccinates, and none of the 16 VG/GA vaccinates died following challenge. There were no obvious differences in pre-challenge serum antibody levels among the vaccinates. Only the twice-vaccinated chickens that were challenged by eyedrop and the unchallenged vaccinates failed to show a marked rise in serum antibody titers. The VG/GA strain of NDV provided protection against the mortality associated with VVNDV challenge similar to that provided by the B-1 strain within the conditions of this experiment.
将8只1日龄的白洛克鸡分为一组，通过滴鼻接种新城疫病毒（NDV）的B - 1株或VG/GA株进行疫苗接种。部分鸡在17日龄时进行第二次接种。8组一次或两次接种疫苗的鸡在30日龄时通过肌肉注射或滴鼻接种致病毒性内脏型新城疫病毒（VVNDV）的加利福尼亚1083株进行攻毒。一组未接种疫苗的对照鸡通过滴鼻进行攻毒。所有8只未接种疫苗的对照鸡、16只接种B - 1疫苗的鸡中有2只、16只接种VG/GA疫苗的鸡中无一在攻毒后死亡。接种疫苗的鸡在攻毒前血清抗体水平无明显差异。只有通过滴鼻攻毒的两次接种疫苗的鸡和未攻毒的接种疫苗的鸡血清抗体滴度未出现明显升高。在本实验条件下，NDV的VG/GA株提供的针对VVNDV攻毒相关死亡率的保护作用与B - 1株相似。
