摘要
Friedt, A. D., McAllister, T. A., He, M. L., Penner, G. B. and McKinnon, J. J. 2014. Effects of replacing barley grain with graded levels of wheat bran on rumen fermentation, voluntary intake and nutrient digestion in beef cattle. Can. J. Anim. Sci. 94: 129–137. Abrasion-milled wheat bran (AMWB) is a relatively new by-product from wheat-based ethanol production. Few published studies are available on the nutritional value of this by-product feed for growing cattle. The objective of this trial was to evaluate the effects of replacing rolled barley with AMWB on apparent nutrient digestibility, voluntary intake and rumen fermentation parameters of beef heifers fed a backgrounding diet formulated to 1.50 and 0.91 Mcal kg−1 dry matter (DM) of NEm and NEg, respectively. Five spayed and rumen-cannulated Angus heifers (584±40 kg) were used in a 5×5 Latin square design. The control diet consisted of 36% barley silage, 24% grass hay, 8% supplement and 32% rolled barley grain (DM basis). Dietary treatments replaced barley grain with AMWB at 8, 16, 24 and 32% of the diet DM. Voluntary DM (P=0.30) and organic matter (OM) (P=0.19) intake were not affected by AMWB inclusion level. Mean rumen pH (P=0.68) as well as duration (min) (P=0.68) and area under the pH curve 5.8 (P=0.27) were not affected by AMWB. Other than acetate, which linearly increased (P=0.03) with increasing AMWB, effects on rumen volatile fatty acids or NH3-N levels were minimal. There was a linear decrease (P<0.01) in DM, OM and gross energy digestibility with increasing AMWB, while acid (P=0.01) and neutral (P=0.03) detergent fibre digestibility decreased in a quadratic manner. A similar quadratic trend (P=0.06) for decreased digestible energy content was also noted with increasing levels of AMWB. Crude protein digestibility was not affected (P=0.94) by treatment. These results indicate AMWB will not support similar gains to barley grain in growing diets due to reduced total tract nutrient utilization and lower digestible energy content.
摘要译文
Friedt，A。D.，McAllister，T.A.，He，M。L.，Penner，G。B. and McKinnon，J。J. 2014.用分级水平的麦麸代替大麦籽粒对瘤胃发酵，肉牛的自愿摄入和营养物质消化的影响。能够。 J. Anim。科学。 94：129-137。磨碎的麦麸（AMWB）是来自小麦乙醇生产的相对较新的副产品。很少有关于这种用于种植牛的副产品饲料的营养价值的公开研究。该试验的目的是评估用AMWB代替卷曲大麦对饲喂背景日粮的牛肉小母牛的表观营养素消化率，自愿摄入量和瘤胃发酵参数的影响，所述背景日粮配制为1.50和0.91 Mcal kg -1 NE m和NE g的干物质（DM）。五个喷射和瘤胃插管的安格斯小母牛（584±40千克）用于5×5拉丁方设计。对照饮食由36％大麦青贮饲料，24％草干草，8％补充剂和32％卷曲大麦谷粒（基于DM）组成。膳食处理用AMWB代替大麦籽粒，占饮食DM的8％，16％，24％和32％。自愿性DM（P = 0.30）和有机物质（OM）（P = 0.19）摄入量不受AMWB包含水平的影响。平均瘤胃pH（P = 0.68）以及持续时间（分钟）（P = 0.68）和pH曲线5.8下的面积（P = 0.27）不受AMWB的影响。除了随着AMWB增加而线性增加（P = 0.03）的醋酸盐，对瘤胃挥发性脂肪酸或NH3-N水平的影响是最小的。随着AMWB的增加，DM，OM和总能量消化率呈线性下降（P <0.01），而酸性（P = 0.01）和中性（P = 0.03）洗涤纤维的消化率呈二次方式下降。随着AMWB水平的增加，还观察到消化能量含量降低的类似二次趋势（P = 0.06）。通过处理，粗蛋白质消化率不受影响（P = 0.94）。这些结果表明，由于总养分利用率降低和消化能含量降低，AMWB不会支持种植日粮中大麦籽粒的类似增益。
A. D. Friedt;[1] T. A. McAllister;[2] M. L. He;[2] G. B. Penner;[1] J. J. McKinnon[1]. Effects of replacing barley grain with graded levels of wheat bran on rumen fermentation, voluntary intake and nutrient digestion in beef cattle[J]. Canadian Journal of Animal Science, 2014,94(1): 129-137