Quigley J D, French P, James R E
Ruminant Products Division, American Protein Corporation, Ames, IA 50010, USA.
J Dairy Sci. 2000 Aug;83(8):1853-5. doi: 10.3168/jds.S0022-0302(00)75056-9.
We fed newborn calves (n = 60) maternal colostrum (n = 12) or a colostral supplement product derived from edible bovine serum (n = 48). Sodium citrate was added to supplements to achieve a final pH of 7.5, 7.0, 6.0, and 5.0. Calves were fed colostrum (2 L/feeding) or supplement (454 g reconstituted in 2 L of water) at 1.2 and 12.6 h of age, which provided a total of 156 (colostrum) or 90 (supplement) g of IgG. We sampled jugular blood at 0 and 24 h of age to determine plasma IgG. Mean plasma IgG concentrations at 0 and 24 h of age were 0 and 6.7 g/L and were markedly higher in calves fed maternal colostrum compared with supplements (10.7 vs. 6.5 g/L) and were higher in Jersey vs. Holstein calves (8.5 vs. 6.1 g/L). Estimated apparent efficiency of IgG absorption was unaffected by treatment and averaged 20%. These data indicate that pH of colostral supplements between 7.5 and 5.0 do not markedly influence the efficiency of IgG absorption.
我们给60头新生小牛喂食初乳（12头）或源自可食用牛血清的初乳补充产品（48头）。在补充产品中添加柠檬酸钠，使最终pH值达到7.5、7.0、6.0和5.0。在小牛1.2小时和12.6小时时，给它们喂食初乳（每次喂食2升）或补充产品（454克产品在2升水中复溶），初乳组提供156克IgG，补充产品组提供90克IgG。在小牛0小时和24小时时采集颈静脉血，以测定血浆IgG。0小时和24小时时的平均血浆IgG浓度分别为0克/升和6.7克/升，与补充产品组相比，喂食初乳的小牛血浆IgG浓度显著更高（10.7克/升对6.5克/升），泽西牛比荷斯坦牛的血浆IgG浓度更高（8.5克/升对6.1克/升）。IgG吸收的表观效率不受处理方式影响，平均为20%。这些数据表明，初乳补充产品pH值在7.5至5.0之间不会显著影响IgG的吸收效率。
