本试验旨在研究不同日粮赖氨酸水平对新生仔猪生长性能、氮利用及体沉积的影响，探讨新生仔猪赖氨酸的需要量。选取4日龄、平均体重为（1.90±0.05） kg的杜×长×大三元杂新生仔猪46头，其中40头按窝别和体重分成5组，每组4个重复，每个重复2头猪，另外6头在试验开始时屠宰，测定体成分；各组日粮赖氨酸水平分别为1.27%（对照组）、1.37%、1.47%、1.57%及1.67%，饲养至21日龄。结果表明：1）1.47%～1.67%组仔猪21日龄体重、15～21日龄及4～21日龄平均日增重显著高于对照组（P<0.05），以1.57%组平均日增重最大。1.57%组和1.67%组在15～21日龄及4～21日龄的平均日采食量显著高于对照组（P<0.05）。1.37%～1.67%组的仔猪料重比均显著低于对照组（P<0.05）。2）1.47%～1.67%组仔猪氮的生物学价值显著高于1.27%～1.37%组（P<0.05）。3）日粮赖氨酸水平未显著影响能量和脂肪沉积（P>0.05）；随日粮赖氨酸水平的提高，蛋白质的每日沉积量增加，1.47%～1.67%组显著高于1.27%～1.37%组（P<0.05），以1.67%组最大。综合各项测定指标得出，4～21日龄仔猪日粮赖氨酸适宜水平为1.57%，即赖氨酸含量为73.1 g/kg CP或0.85 g/MJ DE；仔猪每日赖氨酸需要量为2.43 g/d。

This experiment was aimed to investigate the effects of dietary lysine levels on the growth performance, nitrogen utilization and body deposition of the neonatal piglets, and to determine dietary lysine requirement of the neonatal piglets. In this experiment, a single-factor random test design was used, forty-six 4-day-old neonatal piglets (Duroc×Landrace×Yorkshire) with (1.90±0.05) kg were selected, from which 40 piglets were randomly assigned to 5 dietary groups (4 replicates per group, and 2 piglets per replicate) according to litter and body weight, and the other six piglets were slaughtered to determine the body composition at the trial beginning. The dietary lysine levels were designed as: 1.27% (the control), 1.37%, 1.47%, 1.57% and 1.67%, respectively. The results showed as follows: 1) the use of 1.47%, 1.57%, and 1.67% lysine diets increased BW of piglets at 21-day-old and average daily gain (ADG) at (15～21)-day-old and (4～21)-day-old (P<0.05), and ADG in 1.57% group was the highest. At (15～21)-day-old and (4～21)-day-old, average daily feed intake in 1.57% and 1.67% groups were significantly higher than that in the control group (P<0.05). Supplementing 1.37%～1.67% lysine significantly decreased F/G (P<0.05); 2) the biological value of nitrogen in 1.47% to 1.67% groups were significantly higher than that in 1.27% group and 1.37% group (P<0.05); 3) dietary lysine levels had no influence on energy and fat deposition of piglets (P>0.05). Protein deposition was higher in 1.47%～1.67% groups than those in 1.27%～1.37% groups (P<0.05), where the highest value was in 1.67% group. From these results, it could be concluded that optimal dietary lysine level for neonatal piglet at (4～21)-day-old was 1.57%, that is, 73.1 g/kg CP or 0.85 g/MJ DE, or 2.43 g/d.［Chinese Journal of Animal Nutrition, 2010，22（2）:272-277］