Hammon H M, Zanker I A, Blum J W
Division of Nutrition Pathology, Institute of Animal Breeding, University of Berne, Bern, Switzerland.
J Dairy Sci. 2000 Jan;83(1):85-92. doi: 10.3168/jds.S0022-0302(00)74859-4.
In the neonatal calf, insulin-like growth factor I (IGF-I) concentrations are markedly influenced by the amount of colostrum intake after birth, although colostral IGF-I is barely absorbed. In this study we have investigated effects of delayed colostrum intake in neonatal calves on metabolic traits and on IGF-I, IGF binding proteins (IGFBP), growth hormone (GH), and insulin concentrations in plasma. Calves received colostrum of first milking starting at 2 (GrA), 6 (GrB), 12 (GrC), and 24 h (GrD) after birth. Before third colostrum intake plasma total protein concentrations were higher in GrA than in GrD and plasma glucose concentrations were higher in GrC than GrD. Plasma IGF-I concentrations at first and third colostrum intake were higher in GrA than in GrD. Plasma IGFBP-2 concentrations before first colostrum intake were higher in GrD than in GrA and GrC, and were higher before third colostrum intake in GrD than in GrA. Plasma IGFBP-3 concentrations before first colostrum intake were lower in GrD than in GrA, and before third colostrum intake were lower in GrD than in GrA and GrB. Postprandial plasma insulin concentrations after first colostrum intake were higher in GrA than in GrC and GrD. In conclusion, the plasma IGF-I and insulin status are markedly, albeit transiently, decreased in calves fed colostrum with a delay of 12 to 24 h, and the decreased concentrations of plasma IGF-I were associated with decreased IGFBP-3/IGFBP-2 ratios.
在新生犊牛中，胰岛素样生长因子I（IGF-I）的浓度受出生后初乳摄入量的显著影响，尽管初乳中的IGF-I几乎不被吸收。在本研究中，我们调查了新生犊牛延迟摄入初乳对代谢特征以及血浆中IGF-I、IGF结合蛋白（IGFBP）、生长激素（GH）和胰岛素浓度的影响。犊牛在出生后2小时（A组）、6小时（B组）、12小时（C组）和24小时（D组）开始摄入首次挤奶的初乳。在第三次摄入初乳前，A组的血浆总蛋白浓度高于D组，C组的血浆葡萄糖浓度高于D组。首次和第三次摄入初乳时，A组的血浆IGF-I浓度高于D组。首次摄入初乳前，D组的血浆IGFBP-2浓度高于A组和C组，第三次摄入初乳前，D组的血浆IGFBP-2浓度高于A组。首次摄入初乳前，D组的血浆IGFBP-3浓度低于A组，第三次摄入初乳前，D组的血浆IGFBP-3浓度低于A组和B组。首次摄入初乳后，A组的餐后血浆胰岛素浓度高于C组和D组。总之，延迟12至24小时摄入初乳的犊牛，其血浆IGF-I和胰岛素状态虽只是短暂显著下降，且血浆IGF-I浓度的降低与IGFBP-3/IGFBP-2比值的降低有关。
