摘要
The objective was to determine the effect of replacing barley grain and canola meal with high-lipid by-product pellets (HLBP; 14.6% CP, 29.8% NDF, 9.0% fat, and 5.52 MJ NEg/kg in DM) on DMI, ruminal fermentation, nutrient flow at the omasal canal, and nutrient digestibility. Four ruminally cannulated and ovariectomized Hereford × Gelbvieh heifers (initial BW of 631.9 ± 23.3 kg; mean ± SD) were used in a 4 × 4 Latin square design. Periods consisted of 28 d, including 10 d for diet transition, 11 d for dietary adaptation, and 7 d for measurements. Heifers were fed a typical finishing diet consisting of 89% of concentrate (barley grain and canola meal; CONT), 6% of barley silage, and 5% of mineral and vitamin supplement (on DM basis). Dietary treatments consisted of a CONT or diets where 30% (HLBP30), 60% (HLBP60), and 90% (HLBP90) of the barley grain and canola meal were replaced with HLBP. Dry matter intake was not affected by treatment (P > 0.10). Total short-chain fatty acid concentration and molar proportions of acetate, propionate, and butyrate (P > 0.10) among treatments and ruminal ammonia did not differ (P > 0.10) among treatments, and ruminal ammonia increased (P = 0.03) linearly with increasing HLBP inclusion rate in the diet. Mean and maximum pH increased, whereas the duration and area that pH was below 5.8, 5.5, and 5.2, thresholds used for mild, severe, and acute ruminal acidosis, respectively, decreased linearly (P ≤ 0.05) with increasing rates of inclusion of HLBP. Organic matter flow at the omasal canal increased linearly (P = 0.03) with increasing HLBP inclusion rate in the diet. However, OM digestibility coefficients and apparent ruminal NDF and ADF digestibility yielded negative values for some animals, especially those fed HLBP90, indicating that ruminal digestibility was underestimated. Total tract OM digestibility decreased linearly (P < 0.01) with increasing inclusion rates of HLBP. This study showed that HLBP inclusion in substitution for barley grain and canola meal linearly decreases the severity of ruminal acidosis in cattle fed a typical grain-based finishing diet. However, total tract nutrient digestibility was negatively affected.
摘要译文
目的是确定在DMI上用高脂质副产物颗粒（HLBP; 14.6％CP，29.8％NDF，9.0％脂肪和5.52 MJ NE g / kg在DM中）代替大麦谷物和双低菜粕的效果，瘤胃发酵，Omasal管的营养流动和营养消化率。四个瘤胃插管和切除卵巢的Hereford×Gelbvieh小母牛（初始体重为631.9±23.3 kg;平均值±SD）以4×4拉丁方设计使用。时间为28 d，包括饮食过渡10 d，饮食适应11 d和测量7 d。小母牛饲喂由89％浓缩物（大麦谷物和菜籽粕粉; CONT），6％大麦青贮饲料和5％矿物质和维生素补充物（以DM为基础）的典型整理饮食。膳食处理由CONT或膳食组成，其中30％（HLBP30），60％（HLBP60）和90％（HLBP90）的大麦籽粒和菜籽粕用HLBP代替。干物质摄入量不受治疗影响（P 0.10）。总的短链脂肪酸浓度和乙酸盐，丙酸盐和丁酸盐的摩尔比例（P 0。10）之间的处理和瘤胃氨没有差异（P 0.10），并且随着日粮中的HLBP包含率的增加，瘤胃氨水平增加（P \x3d 0.03）。平均和最大pH值升高，而pH低于5.8,5.5和5.2的持续时间和面积分别为轻度，重度和急性瘤胃酸中毒所使用的阈值线性下降（P≤0）。05）随着HLBP包含率的增加。随着饮食中HLBP包含率的增加，Omasal管的有机物流量呈线性增加（P \x3d 0.03）。然而，OM消化率系数和表观瘤胃NDF和ADF消化率对某些动物产生负值，尤其是那些喂食HLBP90的动物，表明低估了瘤胃消化率。随着HLBP包合率的增加，总管道OM消化率呈线性下降（P 0.01）。该研究表明，用代替大麦籽粒和双低菜粕的HLBP包含线性地降低了喂食典型的基于谷物的整理饮食的牛的瘤胃酸中毒的严重性。然而，总肠道营养物质消化率受到负面影响。