不同精粗比全混合日粮对奶牛产奶性能和牛奶品质的影响

Effects of Different Ratio of Concentrate and Roughage in Total Mixed Ration on Milk Yield and Quality in Dairy Cows

为了研究不同精粗比全混合日粮对奶牛产奶性能和牛奶品质的影响,本试验选取20头中国荷斯坦奶牛,随机分成4组,每组5头,分别饲喂精粗比为80∶20、70∶30、60∶40、50∶50的全混合日粮,测定10 d日均产奶量(kg/d)、10 d日均乳脂率(%)、10 d日均乳蛋白率(%)和10 d日均采食量(kg/d)。结果表明:随着TMR中精料比例减少,产奶量降低,试验组Ⅰ(80∶20)和试验组Ⅱ(70∶30)10 d日均产奶量差异显著(P(0.05),试验组Ⅰ(80∶20)和试验组IV(50∶50)10 d日均产奶量差异极显著(P(0.01)。随着TMR中粗料比例增加,乳脂率增加,试验组Ⅰ(80∶20)、试验组Ⅱ(70∶30)、试验组Ⅲ(60∶40)10 d日均乳脂率差异不显著(P(0.05),但当TMR中粗料达到50%以上时,10 d日均乳脂率显著高于试验组Ⅰ(80∶20)和试验组Ⅱ(70∶30)。随着TMR中精料比例减少,乳蛋白率降低,试验组Ⅱ(70∶30)、试验组Ⅲ(60∶40)、试验组IV(50∶50)乳蛋白率差异不显著(P(0.05),但与试验组Ⅰ(80∶20)差异显著(P(0.05)。随着TMR中精料比例减少,能量水平和蛋白含量降低,10 d日均采食量(kg/d)增加。

In order to study the effect of different ratio of concentrate and roughage in total mixed ration on milk yield and quality in dairy cows,twenty Holstein lactating cows were divided into 4 treatments randomly,with 5 replicates per treatment,four treatments were supplied the total mixed ration（TMR）.Four kinds of ratio were 80∶20（Ⅰ）;70∶30（Ⅱ）;60∶40（Ⅲ） and 50∶50（IV）,respectively.The daily milk yield,percentages of milk fat and protein,feed intake were investigated in day 10 of the trial.The result indicated that as ratio of concentrate decrease in total mixed ration,milk performance and percentages of milk protein decrease,but feed intake increase.The daily milk yield of experimentⅠwere significantly higher（P0.05）than that of experiment Ⅱ,the differences of experimentⅠand experiment IV were extremely remarkable（P 0.01）.The percentages of milk protein of experimentⅠwere significantly higher（P0.05）than that of experiment Ⅱ,experiment Ⅲ,experiment IV.As ratio of roughage increase in total mixed ration,percentages of milk fat increase.As ratio of concentrate decreased in total mixed ration,percentages of protein and energy decreased,the daily feed intake increased.