Beauchemin K A, Farr B I, Rode L M, Schaalje G B
Livestock Sciences Section, Agriculture Canada Research Station, Lethbridge, AB.
J Dairy Sci. 1994 May;77(5):1326-39. doi: 10.3168/jds.S0022-0302(94)77072-7.
Twelve lactating, multiparous Holstein cows were used to evaluate the effects of silage chop length and proportion of long hay in low and adequate forage fiber diets on chewing activities and productivity of cows fed barley-based concentrates. Diets were designed with two forage:concentrate ratios (low forage fiber, 35:65; adequate forage fiber, 65:35), combined with two theoretical chop lengths of alfalfa silage (fine, 5 mm; coarse, 10 mm), and three proportions of long-stemmed alfalfa hay (0, 10, and 20% of DMI). Increasing the chop length of silage in low forage fiber diets did not affect DMI but increased FCM; in adequate forage fiber diets, it decreased DMI and FCM. Addition of hay to silage diets increased DMI, but not FCM yield. Increasing silage chop length in diets formulated below the recommended minimal amount of NDF from forage promoted rumination and increased milk production while maintaining milk fat content and DMI. Addition of a small amount of hay to low forage fiber diets was less effective than increased particle length of silage. In adequate forage fiber diets, finely chopped silage can be used effectively.
选用12头经产泌乳荷斯坦奶牛，以评估青贮料切碎长度和低粗饲料纤维及适宜粗饲料纤维日粮中长干草比例对采食以大麦为基础的精料的奶牛咀嚼活动和生产性能的影响。日粮设计了两种粗饲料与精料比例（低粗饲料纤维，35:65；适宜粗饲料纤维，65:35），并结合两种理论上的苜蓿青贮切碎长度（细，5毫米；粗，10毫米），以及三种长茎苜蓿干草比例（占干物质摄入量的0%、10%和20%）。在低粗饲料纤维日粮中增加青贮料切碎长度对干物质摄入量没有影响，但提高了乳脂校正乳产量；在适宜粗饲料纤维日粮中，它降低了干物质摄入量和乳脂校正乳产量。在青贮日粮中添加干草增加了干物质摄入量，但未提高乳脂校正乳产量。在低于推荐的最低粗饲料中性洗涤纤维量的日粮中增加青贮料切碎长度可促进反刍并提高产奶量，同时维持乳脂含量和干物质摄入量。在低粗饲料纤维日粮中添加少量干草的效果不如增加青贮料颗粒长度。在适宜粗饲料纤维日粮中，可有效使用切碎的青贮料。
