谷氨酰胺对断奶仔猪生长性能、营养物质表观消化率、空肠碱性磷酸酶活性及与肠道健康相关因子基因表达的影响

本研究的目的是探讨饲粮中添加谷氨酰胺对断奶仔猪生长性能、营养物质表观消化率、空肠碱性磷酸酶活性及与肠道健康相关因子基因表达的影响.将128头21日龄断奶的“杜×长×大”三元杂交仔猪按照体重、性别一致的原则随机分成2组,分别为对照组和添加1.00％谷氨酰胺组,每组4个重复,每个重复16头仔猪.在仔猪断奶后第10天和第30天,分别从每个重复中采集新鲜粪便样本,然后选择1头接近平均体重的仔猪进行屠宰,取空肠,刮取黏膜.试验期为30 d.结果表明:在断奶后第10天,与对照组相比,谷氨酰胺组平均日增重、干物质、粗蛋白质表观消化率和表观代谢能分别显著提高了19.05％、9.06％、4.77％和7.02％(P＜0.05),大多数必需氨基酸和非必需氨基酸表观消化率均有显著的提高(P＜0.05);在断奶后第30天,谷氨酰胺组干物质、粗蛋白质表观消化率和表观代谢能分别显著提高了5.90％、2.80％和6.43％ (P ＜0.05).在断奶后第10天和第30天,谷氨酰胺组仔猪空肠刷状缘碱性磷酸酶活性比对照组分别提高了30.09％(P＜0.05)和5.98％ (P ＞0.05).谷氨酰胺组空肠过氧化物酶体增殖体激活受体-γ和丙酮酸激酶基因mRNA表达水平在断奶后第10天比对照组分别下降了10.00％和30.00％ (P ＞0.05);在断奶后第30天比对照组分别显著下降了42.22％和44.52％ (P ＜0.05).在断奶后第10天和第30天,谷氨酰胺组空肠雷帕霉素靶蛋白基因mRNA表达水平分别比对照组提高了22.00％ (P ＞0.05)和22.38％ (P ＜0.05).以上结果提示,谷氨酰胺通过提高空肠碱性磷酸酶活性和调控与肠道健康相关因子基因表达水平来提高断奶仔猪的生长性能和营养物质表观消化率.

Effects of Glutamine on Growth Performance,Apparent Digestibility of Nutrients,Jejunal Alkaline Phosphatase Activity and Expression of Genes Related to Intestinal Health in Weaner Piglets

The aim of the present paper was to provide a profile of the effects of Gln on growth performance,apparent digestibility of nutrients,jejunal alkaline phosphatase activity and expression of genes related to intestinal health in weaner piglets.One hundred and twenty-eight 21-day-old piglets(Duroc×Landrace×Yorkshire) were randomly assigned into control group and 1.00% Gln group according to their body weight and sex,and each group contained 4 replicates and 16 piglets per replicate.The fresh feces samples were collected in each replicate on days 10 and 30 post-weaning,and one piglet was selected for jejunum sample collection based on its weight near to the average weight of the corresponding group.The experiment lasted for 30 days.Results showed that average daily gain,the apparent digestibility of dry matter(DM),crude protein(CP),and apparent metabolizable energy(AME) in the Gln group were increased by 19.05%,9.06%,4.77% and 7.02%(P<0.05)compared with the control group on day 10 post-weaning,and the apparent digestibility of most amino acids in the Gln group were also increased(P<0.05);the apparent digestibility of DM,CP,and AME were increased by 5.90%,2.80% and 6.43%(P<0.05) on day 30 post-weaning.Jejunal brush border membrane-bound alkaline phosphatase activity in the Gln group was increased by 30.09%(P<0.05) and 5.98%(P>0.05) on days 10 and 30 post-weaning,respectively.Peroxisome proliferator-activated receptor gamma(PPAR-γ) and pyruvate kinase(PK) mRNA levels were decreased by 10.00%(P>0.05) and 30.00%(P>0.05) on day 10 post-weaning,and by 41.88% and 44.40%(P<0.05) on day 30 post-weaning.Gln supplementation increased the mammalian target of rapamycin(mTOR) mRNA levels by 22.00%(P>0.05) and 22.38%(P<0.05) on days 10 and 30 post-weaning.These data indicate that Gln increases jejunal alkaline phosphatase activity and expression of genes related to intestinal health,which improves growth performance and apparent digestibility of nutrients in weaner piglets.