Nieto R, Aguilera J F, Fernández-Fígares I, Prieto C
Estación Experimental del Zaidin, Department of Animal Nutrition, Granada, Spain.
Arch Tierernahr. 1997;50(2):105-19. doi: 10.1080/17450399709386124.
Two slaughter experiments were carried out to determine whether the protein content of the diet has an influence upon the efficiency of utilization of ME in fast growing chickens. A normal-protein diet (NPD, 204 g CP/kg DM: 14.7 MJ ME/kg DM) based on soybean meal as the sole source of protein was given at four different levels of intake (ad libitum or restricted at about 90, 65 and 40% ad lib) to 10-d-old animals for 2 weeks. In a parallel experiment the chickens were fed ad libitum a low protein diet (LPD, 66 g CP/kg DM: 15.0 MJ ME/kg DM) based on soybean meal. The intake of metabolizable energy ranged from 1675 to 777 and 1770 to 832 kJ/kgW0.75 per day for NPD and LPD treatments, respectively. Mean values of energy retention, gross efficiency of energy utilization and energy retained as protein were significantly (P < .05) lower and heat production (expressed as both kJ/kgW0.75 per day and kJ/kg body protein content0.75 per day) was significantly higher (P < .05) for the chickens fed on LPD. These findings support the concept of dietary-induced thermogenesis in response to reductions in dietary protein concentration. It is concluded that the increased heat production found in the birds fed on the low-protein diet can be explained by both an increase in energy requirements for maintenance (MEm) and a sharp decrease in the efficiency of utilization of ME of growth (k(g)).
进行了两项屠宰实验，以确定日粮蛋白质含量是否会对快速生长鸡的代谢能利用效率产生影响。以豆粕为唯一蛋白质来源的正常蛋白质日粮（NPD，204 g粗蛋白/kg干物质：14.7 MJ代谢能/kg干物质），以四种不同的采食量水平（自由采食或分别限制在自由采食量的约90%、65%和40%）饲喂10日龄的动物，持续2周。在一项平行实验中，给鸡自由采食以豆粕为基础的低蛋白日粮（LPD，66 g粗蛋白/kg干物质：15.0 MJ代谢能/kg干物质）。NPD和LPD处理组鸡的代谢能摄入量分别为每天1675至777 kJ/kgW0.75和1770至832 kJ/kgW0.75。饲喂LPD的鸡的能量保留平均值、能量利用总效率和以蛋白质形式保留的能量显著（P < 0.05）较低，而产热（以每天kJ/kgW0.75和每天kJ/kg体蛋白含量0.75表示）显著较高（P < 0.05）。这些发现支持了日粮蛋白质浓度降低会引起日粮诱导产热的概念。得出的结论是，饲喂低蛋白日粮的鸡产热增加，这既可以通过维持能量需求（MEm）的增加来解释，也可以通过生长代谢能利用效率（k(g)）的急剧下降来解释。
