不同粗饲料分级指数的粗饲料对奶山羊血液指标及产奶性能的影响

The effect of different grading index of roughage on the dairy goatblood parameters and milk production

本试验研究了GI值不同的粗饲料对奶山羊血液生化指标和产奶性能的影响。选用体重和产奶量相近的40只泌乳中期关中奶山羊,随机分为5组,分别饲喂基础日粮和4种粗饲料分级(GI)指数不同的粗饲料,5个处理组分别为对照组、Ⅰ组(虎尾草)、Ⅱ组(玉米秸秆)、Ⅲ组(羊草)、Ⅳ组(苜蓿)。结果表明:随着饲喂粗饲料GI指数的提高血浆中乙酸、丙酸浓度显著增高(P<0.01),丁酸浓度只有Ⅲ组和Ⅳ组升高显著(P<0.05);血浆中总的氨基酸含量Ⅰ～Ⅳ组分别升高了1.5%、2.4%、3.6%和4.4%;胆固醇、甘油三脂和总蛋白的含量呈升高趋势但差异不显著(P>0.05)。乳脂率的含量Ⅰ～Ⅳ组分别升高了1.5%、2.7%、3.3%、5.1%,其中Ⅳ组显著高于对照组(P<0.05);乳蛋白含量Ⅰ～Ⅳ组分别升高了4.6%、5.6%、6.3%、9.3%;产奶量Ⅰ～Ⅳ组分别提高了4%、5.3%、6.6%、9.3%,其中Ⅳ组显著高于对照组(P<0.01);乳糖和非脂固形物含量变化不显著(P>0.05)。干物质采食量逐渐升高,其中Ⅱ～Ⅳ组显著高于对照组(P<0.01)。随着日粮中粗饲料GI指数的提高,奶山羊血浆中挥发性脂肪酸和总氨基酸的含量及奶中乳脂、乳蛋白的含量均相应提高,GI指数能有效而精确地评定粗饲料的品质。

To study the effect of different grading index GI of roughage on the dairy goat blood biochemical indieatom and milk performance.Forty Guanzhong dairy goats with a similar body weight and milk yield were divided into five groups,fed basal diet and four different GI roughage.Five treatment groups were control group, Group I of Chloris, Group Ⅱ of corn stalks,Group Ⅲ of hay,Group Ⅳ of alfalfa.The results showed that：with the GI index of feeding roughage in- creased,plasma acetic acid and propionie acid concentrations were significantly increased（P 〈 0.01 ）,butyric acid concen- trations in Group Ⅲ and Group IV were increased significantly （P 〈 0.05）;the total amino acid content in plasma of Ⅰ-Ⅳ group were respectively increased by 1.5 % ,2.4 % ,3.6 % and 4.4 % ;the cholesterol,triglycerides and total protein contents tended to increase but the change was not significant （P 〉 0.05）. Fat content of I - Ⅳ group were respectively increased by 1.5 % ,2.7 % ,3.3 % ,5.1% ,of which Group Ⅳ was significantly higher than that of control group （P 〈 0.05）;the milk protein content of I -Ⅳ group were increased by 4.6 %, 5.6%,6.3%, 9.3%,milk yield of I - Ⅳ group were increased by 4 % ,5.3 % ,6.6 % ,9.3 % ,of which Group IV was significantly higher than that of control group （P 〈 0.01） ;lactose and non-fat solids content did not change significantly （P 〉 0.05）.The intake of dry matter gradually in- creased,the Ⅱ-Ⅳ group were significantly higher （P 〈 0.01 ）than that of control group.With the GI of dietary roughage increasing, the volatile fatty acids and total amino acids in the plasma, the milk fat content and milk protein content of the dairy goat increase.The GI index can effectively and accurately assess the quality of the roughage.