本研究旨在探讨不同水平N-氨甲酰谷氨酸（NCG）对断奶仔猪生长性能、养分消化率及血清游离氨基酸的影响。试验选取60头平均体重为（6.4±0.7）kg的26日龄断奶仔猪，按完全随机区组设计分为4个处理，每个处理5个重复，每个重复3头仔猪，分别饲喂含NCG为0、0.04%、0.08%或0.12%的玉米-豆粕型饲粮。结果表明：1）随着NCG添加量的升高，除26～40日龄断奶仔猪平均日增重外，其他日龄阶段仔猪平均日增重和料重比均呈显著的二次曲线改善规律（P<0.05），其中，0.04%和0.08%的NCG对仔猪的促生长效果显著（P<0.05）；2）饲粮中添加0.04%、0.08%和0.12%的NCG，仔猪对饲粮粗蛋白质和磷的消化率呈提高趋势（P>0.05）；3）饲粮中补充低剂量（0.04%）的NCG可显著改善仔猪腹泻状况（P<0.05），与其相比，高剂量（0.12%）的NCG导致26～47日龄仔猪腹泻指数的显著升高（P<0.05）；4）随着饲粮中NCG添加量的增加，仔猪血清游离精氨酸的含量呈线性升高趋势（P=0.077），其中NCG达0.08%以上时，血清游离精氨酸显著高于对照组（P<0.05）。由此可知，饲粮中添加0.04%和0.08%的NCG能显著改善断奶仔猪的生长性能和腹泻状况。综合促生长效果和经济成本，断奶仔猪饲粮中NCG的添加量以0.04%最为合适。

This trial was conducted to study the effects of N-carbamoylglutamate (NCG) on growth performance, nutrient digestibility and serum free amino acids of weaned piglets. Sixty 26-day-old weaned piglets with average weight of (6.4±0.7) kg were randomly divided into 4 treatments with 5 replicates in each treatment and 3 piglets per replicate using a randomized complete-block design, and then were fed one of four diets containing 0, 0.04%, 0.08% and 0.12% NCG, respectively. The results showed as follows: 1) with the increase of NCG supplementation, ADG and F/G of weaned piglets in every stage expect 26～40 days of age were improved in quadratic rule (P<0.05), and 0.04% or 0.08% NCG supplementation significantly improved ADG and F/G of piglets (P<0.05); 2) NCG supplementation enhanced diet protein and phosphorus digestibility (P>0.05); 3) diarrhea ratio and diarrhea index of 0.04% NCG group were lower than those of the control group (P<0.05), but 0.12% NCG, compared with 0.04% NCG, increased diarrhea ratio and diarrhea index (P<0.05); 4) linear increasing trend was observed in free arginine content in serum when NCG was supplemented to diets of piglets （P=0.077）, and free arginine content in serum of 0.08% and 0.12% groups was higher than that of the control group (P<0.05). In conclusion, the growth performance and diarrhea index of weaned piglets were improved by 0.04% or 0.08% NCG supplementation. Considering growth of piglets and cost of NCG, 0.04% was an appropriate and feasible level for NCG supplementation of weaned piglets.［Chinese Journal of Animal Nutrition, 2010，22（4）:1012-1018］