Dubeski P L, d'Offay J M, Owens F N, Gill D R
Department of Animal Science, Oklahoma State University, Stillwater 74078-0425, USA.
J Anim Sci. 1996 Jun;74(6):1367-74. doi: 10.2527/1996.7461367x.
Because feed and water deprivation during marketing and transport of feedlot calves may reduce ruminal B vitamin synthesis at a time when calves are most susceptible to infectious agents, we studied the effect of B vitamin injections on infection and immunity in 12 6-mo-old beef steer calves (153 +/- 8 kg) that were weaned, limit-fed, and deprived of feed. Six calves were injected with B vitamins and ascorbic acid every 48 h for 28 d starting 2 wk before virus inoculation. All calves were infected with an attenuated strain of bovine herpesvirus type 1 (BHV-1) on d 0. From time of arrival (d -20) until the end of a 3-d period without food (d -6), calves lost 13.1% of their initial weight. However, they regained weight after re-feeding so that net weight loss was 7.7% for the 20-d period prior to infection. The stress/BHV-1 model resulted in a mild respiratory infection in all calves with no difference observed between treatment groups. Vitamin injections did not significantly affect virus and interferon titers in nasal secretions, or lymphocyte blastogenesis. However, the B vitamin treatment tended to increase serum IgG titers to BHV-1 on both d 14 (1,120 vs 550, P = .115) and d 28 (2,400 vs 1,830, P = .37) after infection. Averaged across d 14 and d 28, IgG titers tended to be higher (P < .09) for the calves receiving B vitamin injections, indicating that the humoral immune response was enhanced by B vitamin treatment. B vitamin status in stressed calves at the time of vaccination or disease challenge may affect the success of the immune response.
由于育肥牛在销售和运输过程中禁食禁水，可能会在犊牛最易感染病原体时降低瘤胃中B族维生素的合成，因此我们研究了B族维生素注射对12头6月龄肉用公牛犊牛（体重153±8千克）感染和免疫的影响，这些犊牛已经断奶，限制饲喂且处于禁食状态。从病毒接种前2周开始，每48小时给6头犊牛注射B族维生素和抗坏血酸，持续28天。所有犊牛在第0天感染了1型牛疱疹病毒（BHV-1）的减毒株。从到达时（第-20天）到禁食3天结束（第-6天），犊牛体重减轻了初始体重的13.1%。然而，重新喂食后它们恢复了体重，因此在感染前的20天内净体重减轻了7.7%。应激/BHV-1模型导致所有犊牛出现轻度呼吸道感染，各治疗组之间未观察到差异。维生素注射对鼻分泌物中的病毒和干扰素滴度或淋巴细胞增殖没有显著影响。然而，B族维生素治疗在感染后的第14天（1120对550，P = 0.115）和第28天（2400对1830，P = 0.37）均倾向于提高血清中针对BHV-1的IgG滴度。在第14天和第28天进行平均后，接受B族维生素注射的犊牛的IgG滴度往往更高（P < 0.09），这表明B族维生素治疗增强了体液免疫反应。应激犊牛在接种疫苗或疾病攻击时的B族维生素状态可能会影响免疫反应的成功与否。
