本试验通过研究谷氨酸渣对奶山羊产奶量及乳成分的影响，探究谷氨酸渣在奶山羊精料补充料中的最适添加量，旨在丰富奶山羊饲料原料来源，降低饲料成本。本试验采取单因素随机区组设计，选择处于泌乳前期[泌乳天数：（20±5）d]、胎次相同、体重（59.80±2.15）kg、产奶性能相近的2胎健康萨能奶山羊40只，随机分为4组，每组10只。4组山羊所喂精料补充料营养水平基本相同，其中谷氨酸渣的添加量分别为0（对照组）、2%、4%和6%。试验期共63 d，其中预试期7 d，正试期56 d。结果显示：日均干物质采食量、产奶量、乳糖率、乳脂率各组之间差异不显著（P>0.05）。试验第35天时，2%谷氨酸渣组和4%谷氨酸渣组乳蛋白率显著高于对照组和6%谷氨酸渣组（P<0.05）；试验第42天和第56天时，2%谷氨酸渣组、4%谷氨酸渣组和对照组乳蛋白率显著高于6%谷氨酸渣组（P<0.05）。试验第56天时，与对照组相比，各试验组乳蛋白中β-乳球蛋白浓度和绝对产量均表现出上升趋势，2%谷氨酸渣组和4%谷氨酸渣组乳蛋白中β-酪蛋白浓度和绝对产量表现出上升趋势，6%谷氨酸渣组乳蛋白中β-酪蛋白浓度和绝对产量则表现出降低趋势，但差异均不显著（P>0.05）。乳脂、乳糖、乳蛋白的日绝对产量各组之间差异不显著（P>0.05）。由此得出，谷氨酸渣可以作为奶山羊的饲料蛋白质原料，其在奶山羊精料补充料中的最适添加量为4%。

In order to enrich the sources of feedstuffs and reduce the cost for dairy goats, the objective of this study was to evaluate the effects of glutamic acid residue on milk yield and milk composition of dairy goats, and to determine the suitable adding amount of glutamic acid residue in concentrate supplement of dairy goats. A single factor random block design was adopted in this experiment. Forty healthy Saanen dairy goats with similar lactation stage[day in milk:(20±5) days], body weight[(59.80±2.15) kg], parity and milk yield were randomly divided into 4 groups with 10 goats in each group. The nutrient levels of concentrate supplements for 4 groups were basically the same, and the adding amount of glutamic acid residue in concentrate supplements was 0 (control group), 2%, 4% and 6%, respectively. The whole experiment period was 63 days with the pre-test period of 7 days and formal test of 56 days. The results showed that the average daily dry matter intake, milk yield, milk fat percentage, and lactose percentage were not significantly different among all groups (P>0.05). The milk protein percentage at the 35th day of experiment in 2% glutamic acid residue group and 4% glutamic acid residue group was significantly higher than that in control group and 6% glutamic acid residue group (P<0.05), and the milk protein percentage at the 42nd and 56th day of experiment in 2% glutamic acid residue group, 4% glutamic acid residue group and control group was significantly lower than that in 6% glutamic acid residue group (P<0.05). At the 35th day of experiment, the concentration and absolute yield of β-lactoglobulin in milk protein in experimental groups showed an increasing trend, and the concentration and absolute yield of β-casein in 2% glutamic acid residue group and 4% glutamic acid residue group showed an increasing trend, while the concentration and absolute yield of β-casein in 6% glutamic acid residue group showed a decreased trend compared with the control group, but the differences were not significant (P>0.05).The daily absolute yields of milk fat, lactose and milk protein were not significantly different among all groups (P>0.05). It is concluded that the glutamic acid residue can be as the protein feedstuff for dairy goats, and the suitable adding amount of glutamic acid residue in the concentrate supplement for dairy goats is 4%.