Global Ruminant Business Unit, Intervet International bv, Wim de Körverstraat 35, NL-5831 AN Boxmeer, the Netherlands.
BMC Vet Res. 2010 Jan 11;6:2. doi: 10.1186/1746-6148-6-2.
The efficacy of a single dose of an inactivated bovine respiratory syncytial virus (BRSV)--Parainfluenaza type 3 (PI3)--Mannheimia haemolytica (Mh) combination vaccine, in calves positive for maternal antibodies, was established in a BRSV infection study.
As expected the single vaccination did not have any effect on the decline of BRSV-specific neutralising or ELISA antibody. The cellular immune system was however primed by the vaccination. In the vaccinated group virus excretion with nasal discharge was reduced, less virus could be re-isolated from lung tissues and the lungs were less affected.
These results indicate that a single vaccination with an inactivated BRSV vaccine was able to break through the maternal immunity and induce partial protection in very young calves. It can be speculated that the level and duration of protection will improve after the second dose of vaccine is administered. A two-dose basic vaccination schedule is recommended under field conditions.
在牛呼吸道合胞体病毒(BRSV)感染研究中,已证实单剂量的灭活牛呼吸道合胞体病毒(BRSV)-副流感 3 型(PI3)-溶血曼海姆菌(Mh)三联疫苗对具有母源抗体的犊牛有效。
正如预期的那样,单一疫苗接种对 BRSV 特异性中和或 ELISA 抗体的下降没有任何影响。然而,疫苗接种使细胞免疫系统得到了激活。在接种疫苗的组中,鼻分泌物中的病毒排出减少,从肺组织中重新分离出的病毒减少,肺部的影响也较小。
这些结果表明,单次接种灭活的 BRSV 疫苗能够突破母源免疫力,并在非常年幼的犊牛中诱导部分保护。可以推测,在接种第二剂疫苗后,保护水平和持续时间将提高。建议在现场条件下采用两剂基础免疫接种方案。