低蛋白质日粮添加谷氨酸对断奶仔猪营养物质表观消化率、血清生化指标和肝脏发育的影响

Effect of low-protein diet added glutamate on the apparent nutrient digestibility, serum biochemical parameters and liver development in weaned piglets

试验旨在研究低蛋白质日粮中添加谷氨酸对断奶仔猪营养物质表观消化率、血清生化指标、肝脏指数和肝脏酶活性的影响。试验选取18头平均体重为(8.49±0.20)kg的三元杂交断奶仔猪,随机分为3个处理组。按等能原则配制日粮,分为基础日粮组(CP=20.31%)、低蛋白质日粮组(CP=18.37%)和低蛋白质日粮+1.4%谷氨酸组。试验结果表明,与基础日粮组相比,低蛋白质日粮组断奶仔猪对日粮粗蛋白质、粗脂肪和干物质表观消化率显著提高(P<0.05),血清尿素氮含量和肝脏谷丙转氨酶活性显著降低(P<0.05),肝脏γ-谷氨酰转移酶活性显著提高(P<0.05)。与低蛋白质日粮组相比,低蛋白质日粮中添加1.4%谷氨酸可显著增加肝脏指数(P<0.05),并有增加肝脏蛋白质含量(P=0.085)、谷丙转氨酶活性(P=0.069)和降低肝脏γ-谷氨酰转移酶活性(P=0.073)的趋势。结果提示,低蛋白质日粮可促进仔猪对营养物质的消化吸收,而在此基础上添加谷氨酸没有进一步改善的作用;谷氨酸可缓解低蛋白质引起的肝脏γ-谷氨酰转移酶活性升高和谷丙转氨酶活性降低,提高肝脏蛋白质的合成能力,进而促进肝脏发育。

This experiment was conducted to evaluate the effect of glutamate added to low-protein diet on apparent digestibility of nutrients, serum biochemical parameters, liver index and liver enzyme activity in weaned piglets. A total of 18 weaned piglets （Duroc×Landrace×Large White）, with an average of （8.49±0.20） kg, were randomly assigned to 3 dietary treatments with 6 replicates and 1 pig per replicate. The diets were calculated to be isoenergetic and divided into basal diet （CP=20.31%）, low-protein diet （CP=18.37%）, and low-protein diet added 1.4% glutamate, respectively. The results indicated that low-protein diet significantly increased the apparent digestibility of crude protein, crude fat and dry matter and the activity of liver gamma-glutamate transferase （γ-GT）（P〈0.05）, and decreased the concentration of serum urea nitrogen （SUN） and the activity of liver glutamate pyruvate transaminase （ALT） （P〈0.05）. The supplementation of 1.4% glutamate to low-protein diet had the tendency to increase the concentration of liver protein （P=0.085）, the activity of liver ALT （P=0.069）, and decrease the activity of liver γ-GT （P=0.073）, and significantly increased the liver index of Dies （P〈0.05）.Thus speculate that low-protein diet could promote the digestion and absorption of nutrients in piglets. The supplementation of glutamate could maintain the stability of liver γ-GT and ALT activities, enhance the ability of liver to synthesize protein, and improve liver growth.