Hostettler-Allen R L, Tappy L, Blum J W
Division of Nutritional Pathology, University, Berne, Switzerland.
J Anim Sci. 1994 Jan;72(1):160-73. doi: 10.2527/1994.721160x.
In intensively milk-fed calves post-prandial glucose (G) and insulin (I) concentrations, but not preprandial G concentrations, increased or failed to decrease during the growth period, compared with data from calves that were progressively weaned. This study was, therefore, designed to investigate G and I metabolism in veal calves. Euglycemic-hyperinsulinemic and hyperglycemic clamps in the unfed state demonstrated mutual responsiveness of I and G, but revealed a relative I resistance. After feed consumption, I resistance was exaggerated, as seen by decreased G clearance rates after i.v. G and I administration in fed compared with unfed calves. Milk replacer is a source of readily available lactose, fat, and protein, the intake of which, on a kilogram.75 basis, gradually increased with age. Increased substrate availability and effects of nutrients themselves were probably responsible for elevated plasma concentrations of G and I and led to I resistance. Additionally, hyperglycemia > 1.5 g/L was followed by urinary excretion of G.
与逐渐断奶的犊牛的数据相比，在集约化人工哺乳的犊牛中，餐后葡萄糖（G）和胰岛素（I）浓度在生长期间会升高或未能降低，但餐前G浓度则不然。因此，本研究旨在调查小牛肉用犊牛的G和I代谢。在未进食状态下的正常血糖-高胰岛素钳夹试验和高血糖钳夹试验表明，I和G具有相互反应性，但显示出相对的I抵抗。进食后，I抵抗加剧，与未进食的犊牛相比，喂食后的犊牛静脉注射G和I后G清除率降低即可看出。代乳品是易于获取的乳糖、脂肪和蛋白质的来源，按每千克体重计算，其摄入量会随着年龄的增长而逐渐增加。底物可用性的增加和营养物质本身的作用可能是导致血浆G和I浓度升高并导致I抵抗的原因。此外，血糖浓度>1.5 g/L后会出现G的尿排泄。
