Department of Animal Science, Macdonald Campus, McGill University, Sainte-Anne-de-Bellevue, Quebec, Canada H9X 3V9.
J Dairy Sci. 2012 Feb;95(2):859-63. doi: 10.3168/jds.2011-4884.
The objective of this study was to determine the feeding value of sweet sorghum silage (SS) for dairy cows compared with alfalfa silage (AS). Two diets were formulated with a 50:50 forage:concentrate ratio. Sweet sorghum silage and AS constituted 70% of the forage in each diet (dry matter basis). Twelve lactating Holstein cows in early lactation were used in a crossover experiment. Relative to AS, SS contained 58% more neutral detergent fiber and 36.6 and 72.7% less acid detergent lignin and crude protein, respectively. Milk yield (33.0 vs. 36.7 kg/d) was lower for cows fed SS than for those fed AS. However, dry matter intake, energy-corrected milk, and feed efficiency were similar for both dietary treatments. Replacing AS with SS increased concentrations of milk fat (4.44 vs. 3.80%) and total solids (13.31 vs. 12.88%) and reduced concentrations of milk lactose (4.55 vs. 4.61%), milk solids-not-fat (8.88 vs. 9.08%), and milk urea nitrogen (10.0 vs. 14.0 mg/dL). We concluded that replacing AS with SS had negative effects on milk yield, whereas dry matter intake, energy-corrected milk, and milk efficiency were similar.
本研究旨在确定与苜蓿青贮（AS）相比，甜高粱青贮（SS）对奶牛的饲用价值。两种日粮均采用 50:50 的粗饲料：精料比进行配制。SS 和 AS 分别占每个日粮中 70%的粗饲料（干物质基础）。12 头泌乳早期荷斯坦奶牛用于交叉试验。与 AS 相比，SS 含有 58%更多的中性洗涤纤维，且酸性洗涤木质素和粗蛋白含量分别低 36.6%和 72.7%。与 AS 相比，饲喂 SS 的奶牛产奶量（33.0 比 36.7kg/d）更低。然而，两种日粮处理的干物质采食量、能量校正奶和饲料效率相似。用 SS 替代 AS 提高了牛奶脂肪（4.44 比 3.80%）和总固体（13.31 比 12.88%）的浓度，降低了牛奶乳糖（4.55 比 4.61%）、乳脂非脂（8.88 比 9.08%）和牛奶尿素氮（10.0 比 14.0mg/dL）的浓度。我们得出结论，用 SS 替代 AS 对产奶量有负面影响，而干物质采食量、能量校正奶和牛奶效率相似。
