Calberry J M, Plaizier J C, Einarson M S, McBride B W
Department of Animal and Poultry Science, University of Guelph, Guelph, ON, Canada N1G 2W1.
J Dairy Sci. 2003 Nov;86(11):3611-9. doi: 10.3168/jds.S0022-0302(03)73967-8.
The effects of replacing chopped alfalfa hay with alfalfa silage in a total mixed ration containing barley grain and corn silage on production and rumen conditions were investigated. Cows received three diets that all contained (dry matter basis) 38.5% barley grain-based energy supplement, 30.5% corn silage, 17.0% protein supplement, and 4.2% sunflower seeds. One diet contained (dry matter basis) 9.8% of chopped alfalfa hay and no alfalfa silage. One diet contained (dry matter basis) 4.9% chopped alfalfa hay and 4.9% alfalfa silage. One diet contained (dry matter basis) 9.8% of alfalfa silage and no chopped alfalfa hay. Contents of crude protein, neutral detergent fiber, acid detergent fiber, and starch, averaged across diets, were 16.7, 41.3, 21.1, and 24.4% DM, respectively, and did not differ significantly among diets. Replacing chopped alfalfa hay with alfalfa silage decreased the proportion of dietary DM passing through the 8-mm screen of the Penn State Particle Separator from 61.9 to 55.2% dry matter and significantly increased dietary physical effective NDF (peNDF) content, calculated as the NDF retained by the two screens of the Penn State Particle Separator, from 20.1 to 23.3% DM. Replacing chopped alfalfa hay with alfalfa silage also reduced dietary DM content, increased rumen pH from 6.27 to 6.47, reduced volatile fatty acid concentrations, numerically increased milk fat concentration and milk fat yield. Milk yield, milk protein concentration, dry matter intake, and rumen ammonia concentration were not affected.
研究了在含有大麦谷物和玉米青贮饲料的全混合日粮中，用苜蓿青贮饲料替代切碎苜蓿干草对奶牛生产性能和瘤胃状况的影响。奶牛采食三种日粮，所有日粮（干物质基础）均包含38.5%的大麦谷物能量补充料、30.5%的玉米青贮饲料、17.0%的蛋白质补充料和4.2%的向日葵籽。一种日粮（干物质基础）包含9.8%的切碎苜蓿干草且不含苜蓿青贮饲料。一种日粮（干物质基础）包含4.9%的切碎苜蓿干草和4.9%的苜蓿青贮饲料。一种日粮（干物质基础）包含9.8%的苜蓿青贮饲料且不含切碎苜蓿干草。日粮中粗蛋白、中性洗涤纤维、酸性洗涤纤维和淀粉的含量（各日粮平均值）分别为16.7%、41.3%、21.1%和24.4%干物质，各日粮间无显著差异。用苜蓿青贮饲料替代切碎苜蓿干草，使通过宾夕法尼亚州立大学颗粒分离器8毫米筛网的日粮干物质比例从61.9%降至55.2%，并显著提高了日粮物理有效中性洗涤纤维（peNDF）含量，按宾夕法尼亚州立大学颗粒分离器两层筛网截留的中性洗涤纤维计算，从20.1%提高到23.3%干物质。用苜蓿青贮饲料替代切碎苜蓿干草还降低了日粮干物质含量，使瘤胃pH值从6.27提高到6.47，降低了挥发性脂肪酸浓度，使乳脂肪浓度和乳脂肪产量略有增加。产奶量、乳蛋白浓度、干物质采食量和瘤胃氨浓度未受影响。
