TMR不同精粗比例对中产奶牛碳水化合物消化的影响

Effects of different concentrate to forage ratio of TMR on carbohydrate digestibility of mid-yielding dairy cattle

以40头中等产奶量的荷斯坦奶牛为研究对象,应用随机分组试验设计将试验动物分为Ⅰ、Ⅱ、Ⅲ和Ⅳ组,日粮精粗比例依次为50%:50%,40%:60%,35%:65%,30%:70%。研究TMR不同精粗比例对奶牛碳水化合物消化的影响,结果表明:随着粗饲料比例增加,CF、NFE、NDF和ADF表观消化率均呈先增加后降低趋势;其中试验Ⅱ组CF表观消化率显著(P<0.05)高于试验Ⅰ组,试验Ⅲ组极显著(P<0.01)高于试验Ⅰ组和Ⅳ组;试验Ⅲ组NDF表观消化率最高,并显著(P<0.05)高于试验Ⅳ组;试验Ⅱ的ADF表观消化率组较高,但各组间均差异不显著(P>0.05)。通过比较发现,当TMR日粮中粗饲料比例在60%~65%时各试验组CF、NDF、ADF和NFE表观消化率均较高,即碳水化合物消化利用最充分。因此,TMR的精粗比例为(40%:60%)^(35%:65%)是中产奶牛TMR较适宜的比例。

The paper researched the effects of different concentrate to forage ratio of TMR on carbohydrate digestibility of mid-yielding dairy cattle.Forty animals were randomly divided into four groups： treatmentⅠ,Ⅱ,Ⅲ and Ⅳ（treatmentⅠwas the control）,and the ratio of concentrate to forage were 50%：50%,40%：60%,35%：65%,30%：70% respectively.The diet including concentrates,alfalfa hay,Leymus chinensis and corn silage was made into TMR（Total Mixed Rations）.The results showed the apparent digestbility of CF,NDF,ADF and NFE were all increasing from treatmentⅠto Ⅲ then decresing.And CF apparent digestbility in treatment Ⅲwas higher significantly（P0.01） than treatmentⅠand Ⅳ;NDF apparent digestbility in treatment Ⅲ was significantly higher（P0.05） than treatmentⅣ.According to statistics the apparent digestbility of CF、NDF、ADF and NFE was highest when roughage ratio in diet was 60% to 65%.In conclusion,carbohydrate in diet was utilized sufficiently when concentrate to forage ratio was（40%：60%）^（35%︰65%）.