Imai K, Ohnaka M, Niiyama Y
J Nutr Sci Vitaminol (Tokyo). 1986 Oct;32(5):513-25. doi: 10.3177/jnsv.32.513.
The effects of dietary protein on the maintenance energy requirement (MEm) and net utilization efficiency of metabolizable energy for growth (MEg) were investigated by regression analysis of energy balance with various energy intakes. Weanling rats of the Wistar strain, weighing about 85 g, were given a diet containing 0 to 70% casein freely or in restricted amounts (equivalent to two-thirds or one-third of the intake of the ad libitum group) for 5 days. The MEm was fairly constant in rats given 10 to 50% casein diets, being about 29 kcal/100 g BW/day, but increased at higher or lower dietary protein levels, indicating inefficient energy utilization in protein-malnourished animals. From the slope of the regression line between energy balance and metabolizable energy intake, the net energetic efficiencies for growth were estimated as 68, 71, 74, 77, 82, 83, 80, 78, 77 and 74% with 0, 3, 6, 10, 20, 30, 40, 50, 60 and 70% casein diets, respectively. Weanling rats fed 20 to 30% casein diets utilized the dietary energy for growth most efficiently. At protein levels higher or lower than 20 to 30%, the efficiency was less, showing that MEg utilization depended on dietary protein. The energy necessary for 1 g body weight gain was 2.6 kcal in rats receiving 30% casein diet, but increased with an increase or decrease in the protein level. These data on the food efficiency, MEm, the net efficiency of MEg and the energy necessary for 1 g weight gain show that dietary protein affects energy utilization and that protein-malnourished animals use energy inefficiently.
通过对不同能量摄入量下能量平衡进行回归分析，研究了膳食蛋白质对维持能量需求（MEm）和生长代谢能净利用效率（MEg）的影响。选用体重约85g的Wistar品系断乳大鼠，给予含0%至70%酪蛋白的饲料，自由采食或限量采食（相当于随意采食组摄入量的三分之二或三分之一），持续5天。给予含10%至50%酪蛋白饲料的大鼠，其MEm相当恒定，约为29kcal/100g体重/天，但在膳食蛋白质水平较高或较低时会升高，这表明蛋白质营养不良的动物能量利用效率低下。根据能量平衡与代谢能摄入量之间回归线的斜率，估计0%、3%、6%、10%、20%、30%、40%、50%、60%和70%酪蛋白饲料组的生长净能量效率分别为68%、71%、74%、77%、82%、83%、80%、78%、77%和74%。饲喂含20%至30%酪蛋白饲料的断乳大鼠对膳食能量的生长利用效率最高。在蛋白质水平高于或低于20%至30%时，效率较低，表明MEg的利用取决于膳食蛋白质。摄入30%酪蛋白饲料的大鼠每增加1g体重所需能量为2.6kcal，但随着蛋白质水平的升高或降低而增加。这些关于食物效率、MEm、MEg净效率以及每增加1g体重所需能量的数据表明，膳食蛋白质会影响能量利用，且蛋白质营养不良的动物能量利用效率低下。
