Williams V J, Senior W
J Nutr. 1981 Apr;111(4):581-5. doi: 10.1093/jn/111.4.581.
Metabolic fecal nitrogen was measured in young adult female rats fed synthetic diets before and after weight losses had been caused by restricted food intake. When food intake was decreased from 5.5 to 2.4 g or from 6.7 to 2.3 g per 100 g body weight per day, metabolic fecal nitrogen per gram food intake increased by 48 and 59%, respectively. However, weight losses did not affect metabolic fecal nitrogen excretion significantly until some 40% loss of weight had been obtained. At this point metabolic fetal nitrogen excretion was observed to increase by 11%. These results indicate that the 6% increase in apparent digestibility of crude protein in a stock diet which occurs during food restriction is due to a genuine increase in absorption of dietary nitrogen.
在通过限制食物摄入量导致体重减轻之前和之后，对喂食合成饲料的成年雌性幼鼠的代谢粪氮进行了测量。当食物摄入量从每天每100克体重5.5克降至2.4克或从6.7克降至2.3克时，每克食物摄入量的代谢粪氮分别增加了48%和59%。然而，体重减轻直到体重减轻约40%之前，对代谢粪氮排泄没有显著影响。此时，观察到代谢粪氮排泄增加了11%。这些结果表明，在食物限制期间，基础日粮中粗蛋白表观消化率增加6%是由于膳食氮吸收的真正增加。
