Sultan Javed I, Javaid Asif, Aslam Muhammad
Institute of Animal Nutrition and Feed Technology, University of Agriculture, Faisalabad, 38040, Pakistan.
Trop Anim Health Prod. 2010 Jun;42(5):941-6. doi: 10.1007/s11250-009-9511-8. Epub 2009 Dec 13.
Thirty-six Thalli male growing lambs were used in a completely randomized design with 2 x 2 factorial arrangement of treatments to evaluate the effect of varying levels of energy and protein on nutrient intake, digestibility, weight gain, and gain to feed ratio. Four experimental diets, i.e., low energy-low protein (LE-LP), low energy-high protein (LE-HP), high energy-low protein (HE-LP), and high energy-high protein (HE-HP) were formulated. The low- and high-energy diets contained 2.3 and 2.7 MJ/kg dry matter (DM) with 12% and 14% of crude protein. The lambs were fed ad libitum. Dietary energy and protein levels and their interactions influenced the nutrient intake. Maximum dry matter intake was noted in animals fed LE-HP diet followed by LE-LP, HE-HP, and HE-LP diets. Digestibility of DM and N increased (P < 0.01) and that of neutral detergent fiber decreased (P < 0.01) linearly with increasing levels of dietary energy and protein. Digestibility of N was only affected by protein level and interaction between energy and protein levels. Average daily gain was higher (P < 0.01) in lambs fed HE-HP diet followed by LE-HP, LE-LP, and HE-LP diets. Dietary energy and protein levels and their interaction had significant effect (P < 0.01) on gain to feed ratio.
选用36只生长中的雄性羔羊，采用完全随机设计和2×2析因处理安排，以评估不同能量和蛋白质水平对营养物质摄入量、消化率、体重增加以及增重耗料比的影响。配制了四种试验日粮，即低能量-低蛋白（LE-LP）、低能量-高蛋白（LE-HP）、高能量-低蛋白（HE-LP）和高能量-高蛋白（HE-HP）日粮。低能量和高能量日粮的干物质（DM）含量分别为2.3和2.7 MJ/kg，粗蛋白含量分别为12%和14%。羔羊自由采食。日粮能量和蛋白质水平及其交互作用影响营养物质摄入量。采食LE-HP日粮的动物干物质摄入量最高，其次是LE-LP、HE-HP和HE-LP日粮。随着日粮能量和蛋白质水平的提高，DM和N的消化率呈线性增加（P<0.01），中性洗涤纤维的消化率呈线性下降（P<0.01）。N的消化率仅受蛋白质水平以及能量和蛋白质水平之间交互作用的影响。采食HE-HP日粮的羔羊平均日增重较高（P<0.01），其次是LE-HP、LE-LP和HE-LP日粮。日粮能量和蛋白质水平及其交互作用对增重耗料比有显著影响（P<0.01）。
