Abstract: Glutamine has an essential role with a beneficial function in improving the nutrition status of young mammals. The influence of L-Glutamine (Gln) on the Coefficient of Total Tract Apparent Digestibility (CTTAD) and Apparent Ileal Digestibility (AID), the jejunal enzyme activity associated with nutrient absorption and the energy production in weaned piglets has not been sufficiently studied. The aim of the present study is to provide a profile of the effects of Gln on CTTAD, AID, the activities of jejunal enzymes in connection with nutrient digestion and absorption and energy production. The piglets were weaned at 21 days of age. There were two groups in Experiment 1 and 2 representing supplementation with 0 or 1% Gln to the basal diet. In Experiment 1, the CTTAD of the dietary components and energy was assessed at 3, 5, 10, 15 and 30 days after weaning. In Experiment 2, productive performance, AID, jejunal enzyme activities and expression of Peroxisome Proliferator-Activated Receptor gamma (PPARγ) were measured at 10 and 30 days post-weaning. Results showed that dietary Gln supplementation significantly improved the CTTAD of DM, OM, GE and AA and the CTTAD increased significantly with the extension of days after weaning. For the entire experiment, the average daily gain increased by 12.40% (p = 0.049) in the Gln group. Dietary Gln supplementation increased the AID of GE, Leu, Lys, Cys and Pro by 12.50 (p = 0.047), 7.03% (p = 0.041), 5.95% (p = 0.036), 9.30 (p = 0.025), 11.17% (p = 0.009), respectively at 10 days post-weaning; Pro by 6.11% (p = 0.044) at 30 days post-weaning. Jejunal brush border membrane-bound alkaline phosphatase activity increased in the Gln-supplemented pigs by 30.36% (p = 0.048) and 6.21% (p = 0.30) at 10 and 30 days post-weaning, respectively. Compared with the control pigs, the mRNA level of PPARγ decreased by 10.85% (p = 0.14) and 41.88% (p = 0.023) after the administration of 1% Gln for 10 and 30 days, respectively. The activity of glutamine synthetase decreased by 48.89% (p = 0.044) at 10 days post-weaning and pyruvate kinase by 13.13% (p = 0.036) at 30 days post-weaning in the Gln-supplemented pigs. In conclusion, 1% Gln supplementation to the post-weaned piglet diet enhanced the CTTAD and AID of diet, improved intestinal absorption and modified jejunal enzyme activities related to Gln metabolism and energy production.
Y.P. Xiao, X.Y. Li , T.X. Wu , L. Yang , Q.H. Hong , C.M. Yang and A.G. Chen , 2012. Effects of Dietary Glutamine Supplementation on Nutrient Absorption and Activity of Enzymes Involved in Glutamine Metabolism and Energy Production in the Jejunum of Weaned Piglets. Journal of Animal and Veterinary Advances, 11: 1441-1449.