中文摘要：

本试验研究了日粮中添加不同水平N-氨甲酰谷氨酸（N-carbamylglutamate,NCG）对妊娠后期母猪繁殖性能的影响,并对其作用机理进行初步探讨。选用妊娠80d的长大母猪32头,随机分成4组（对照组和试验组1、2、3）,每组8个重复。对照组饲喂基础日粮,试验组在基础日粮中分别添加0.04%、0.08%、0.12%NCG。母猪妊娠第110天采血分离血浆用于测定血浆游离氨基酸、NO、NOS、激素含量和血液生化指标。结果表明,母猪妊娠后期日粮中添加0.08%NCG比空白对照组窝产活仔数提高11.75%（10.75vs.9.62,0.05

英文摘要：

This study was conducted to investigate the effects and potential mechanisms of dietary N-carbamylglutamate（NCG） supplementation during late gestation on the reproductive performance of sows.Thirty-two Landrace × Large White sows on d 80 of gestation were assigned randomly to 4 groups（control group and experimental group 1,2,3）,8 replicates in each group.Sows in the control group were fed with basic diet,and those in the experimental groups were fed with basic diet supplemented with 0.04%,0.08% and 0.12% NCG.Blood samples were obtained on d 110 of gestation to examine the plasma concentration of free amino acids,NO,NOS,hormones and biochemical indices.The results showed that supplementation with 0.08% NCG increased the number of piglets born alive by 11.75%（10.75 vs.9.62,0.05P0.1） and live litter birth weight by 13.23%（16.52 kg vs.14.59 kg,P0.05）,decreased piglets born dead per litter by 57.14%（0.75 vs.1.75,P0.05） and plasma urea nitrogen concentration compared with the control group,and increased plasma concentration of arginine,NO,NOS,growth hormone and Zn＋ too（P0.05）.0.04% and 0.12% NCG enhanced the reproductive performance of sows.The result suggest that dietary NCG supplementation could enhance reproductive performance of sows,and the potential mechanisms is that the supplemented NCG increases endogenous arginine synthesis in sows,so as to improve intrauterine environment and fetal nutrition,and guarantee fetus survival and growth.