Ipharraguerre I R, Ipharraguerre R R, Clark J H
Department of Animal Sciences, University of Illinois, Urbana 61801, USA.
J Dairy Sci. 2002 Nov;85(11):2905-12. doi: 10.3168/jds.S0022-0302(02)74378-6.
Fifteen multiparous Holstein cows averaging 112 d in milk were used in a replicated 5 x 5 Latin square to evaluate the incremental substitution of soyhulls for corn in the diet. Diets contained 23% alfalfa silage, 23% corn silage, and 54% concentrate on a dry matter basis. Pelleted soyhulls replaced corn in the concentrate to supply 0, 10, 20, 30, or 40% of the dietary dry matter. Dry matter intake decreased linearly as soyhulls replaced corn in the diet, but the major decrease in dry matter intake occurred when soyhulls provided 30 and 40% of the dietary dry matter. Intakes of both acid and neutral detergent fiber increased linearly as soyhulls increased from 0 to 40% of dietary dry matter. Production of milk tended to decrease when soyhulls supplied 40% of the dietary dry matter. Production of 3.5% fat-corrected milk, milk crude protein percentage and yield, milk urea N, and total solids yield were not affected by treatments. Production of true protein, but not percentage, tended to decrease by about 5% when soyhulls supplied 40% of the dietary dry matter. Increasing the percentage of soyhulls in the dietary dry matter increased linearly milk fat content and yield, and total solids content in milk. These data suggest that soyhulls can successfully supply up to about 30% of the dry matter intake of midlactation cows without depressing animal performance. Furthermore, replacing part of the corn with soyhulls in high grain diets may be viable when milk fat has a high monetary value or when soyhulls can be purchased at a more competitive price than grains on a nutrient content basis.
选用15头经产荷斯坦奶牛（平均产奶112天），采用重复5×5拉丁方设计，评估日粮中用大豆皮逐步替代玉米的效果。日粮以干物质计，包含23%苜蓿青贮、23%玉米青贮和54%精料。在精料中用颗粒状大豆皮替代玉米，使大豆皮提供日粮干物质的0%、10%、20%、30%或40%。随着日粮中大豆皮替代玉米，干物质采食量呈线性下降，但当大豆皮提供日粮干物质的30%和40%时，干物质采食量下降幅度较大。随着大豆皮占日粮干物质的比例从0增加到40%，酸性洗涤纤维和中性洗涤纤维的采食量均呈线性增加。当大豆皮提供日粮干物质的40%时，产奶量有下降趋势。3.5%乳脂校正乳产量、乳粗蛋白百分比和产量、乳尿素氮以及总固体产量不受处理影响。当大豆皮提供日粮干物质的40%时，真蛋白产量（而非百分比）有下降约5%的趋势。日粮干物质中大豆皮比例增加，乳脂含量和产量以及乳中总固体含量呈线性增加。这些数据表明，大豆皮能够成功提供高达约30%的泌乳中期奶牛干物质采食量，而不影响动物生产性能。此外，当乳脂具有较高经济价值或大豆皮在营养成分基础上比谷物能以更具竞争力的价格购得时，在高谷物日粮中用大豆皮替代部分玉米可能是可行的。
