Cummins K A, Brunner C J
Department of Animal and Dairy Sciences, College of Agriculture, Auburn University 36849.
J Dairy Sci. 1989 Jan;72(1):129-34. doi: 10.3168/jds.S0022-0302(89)79088-3.
Colostrum-fed, colostrum-deprived, and colostrum-fed and colostrum-deprived calves fed ascorbic acid (1.75 g/d) in whole, raw milk to 6 wk of age were sampled from 0 to 8 wk of age in order to determine whether ascorbate supplementation would increase plasma Ig concentrations, antibody response to immunization, and disease resistance. Plasma IgG concentrations were lower at 14 and 28 d of age in calves fed ascorbate compared with plasma concentrations in calves not receiving ascorbate supplementation, irrespective of colostrum feeding. Colostrum feeding had no effect on antibody titer to keyhole limpet hemocyanin at any age, but ascorbate-supplemented calves had lower plasma antibody titers to keyhole limpet hemocyanin at 35 and 56 d of age. Calves fed ascorbate had lower clinical scores for diarrhea. Dietary ascorbate does not appear to be immunostimulatory in dairy calves to 56 d of age and appeared to inhibit antibody synthesis. However, at 14 d of age there was an interaction of ascorbate supplementation and colostrum feeding; plasma IgG concentrations were higher in colostrum-deprived calves fed ascorbate then in colostrum-deprived calves not fed ascorbate.
从出生0至8周龄期间，采集了初乳喂养、未喂初乳以及初乳喂养和未喂初乳且在全脂生牛奶中添加抗坏血酸（1.75克/天）至6周龄的犊牛样本，以确定补充抗坏血酸盐是否会提高血浆免疫球蛋白浓度、对免疫接种的抗体反应以及抗病能力。无论初乳喂养情况如何，与未补充抗坏血酸盐的犊牛相比，补充抗坏血酸的犊牛在14日龄和28日龄时血浆免疫球蛋白G浓度较低。初乳喂养对任何年龄的血蓝蛋白抗体滴度均无影响，但补充抗坏血酸的犊牛在35日龄和56日龄时血蓝蛋白血浆抗体滴度较低。补充抗坏血酸的犊牛腹泻临床评分较低。在56日龄之前，日粮中的抗坏血酸盐对奶牛犊牛似乎没有免疫刺激作用，反而似乎抑制了抗体合成。然而，在14日龄时，抗坏血酸盐补充和初乳喂养之间存在相互作用；补充抗坏血酸的未喂初乳犊牛的血浆免疫球蛋白G浓度高于未补充抗坏血酸的未喂初乳犊牛。
