Hall K L, Goetsch A L, Forster L A
Dept. of Anim. and Poult. Sci., University of Arkansas, Fayetteville 72701.
J Anim Sci. 1990 Jun;68(6):1674-82. doi: 10.2527/1990.6861674x.
Two latin squares were conducted to determine the effects on feed intake and nutrient digestion of adding a ruminal buffer or DL-methionine to supplemental ground corn for Holstein steers (avg BW of 286 and 222 kg in Exp. 1 and 2, respectively) with ad libitum access to bermudagrass hay. In Exp. 1, steers were not supplemented (control) or were given .5 (LC) or 1.0% BW/d (HC) of ground corn without or with .021% BW of sodium bicarbonate (B). Total DMI was 2.39, 2.71, 2.79, 2.81 and 2.98% BW (effects of supplementation [P less than .05], level of corn [P less than .05] and buffer [P less than .06]), and OM digested was 3.56, 4.65, 4.65, 4.96 and 5.34 kg/d for control, LC, LCB, HC and HCB, respectively (effects of supplementation and corn level, P less than .05). In Exp. 2, corn levels were .24 and .74% BW/d and .0022% BW of DL-methionine (M) replaced B. Total DMI was 2.85, 3.00, 2.99, 3.22 and 3.34% BW (effects of supplementation and corn level, P less than .05), and digestible OM intake was 3.78, 4.24, 4.30, 4.84 and 5.12 kg/d for control, LC, LCM, HC and HCM, respectively (effects of supplementation and corn level, P less than .05). Overall, changes in feed intake and digestion with additions of a ruminal buffer and DL-methionine to corn supplements were not marked; however, buffer addition increased DMI intake to the greatest degree with 1.0% BW/d of corn.
进行了两个拉丁方试验,以确定在给荷斯坦阉牛(试验1和试验2中平均体重分别为286千克和222千克)补饲粉碎玉米时添加瘤胃缓冲剂或DL-蛋氨酸对采食量和养分消化率的影响,这些阉牛可自由采食百慕大干草。在试验1中,阉牛不补饲(对照),或给予0.5%(低水平补饲,LC)或1.0%体重/天(高水平补饲,HC)的粉碎玉米,分别添加或不添加0.021%体重的碳酸氢钠(B)。总干物质采食量分别为体重的2.39%、2.71%、2.79%、2.81%和2.98%(补饲的影响[P小于0.05]、玉米水平的影响[P小于0.05]和缓冲剂的影响[P小于0.06]),对照、LC、LCB、HC和HCB组的有机物消化量分别为3.56千克/天、4.65千克/天、4.65千克/天、4.96千克/天和5.34千克/天(补饲和玉米水平的影响,P小于0.05)。在试验2中,玉米水平为0.24%和0.74%体重/天,用0.0022%体重的DL-蛋氨酸(M)替代B。总干物质采食量分别为体重的2.85%、3.00%、2.99%、3.22%和3.34%(补饲和玉米水平的影响,P小于0.05),对照、LC、LCM、HC和HCM组的可消化有机物摄入量分别为3.78千克/天、4.24千克/天、4.30千克/天、4.84千克/天和5.12千克/天(补饲和玉米水平的影响,P小于0.05)。总体而言,在玉米补充料中添加瘤胃缓冲剂和DL-蛋氨酸对采食量和消化率的影响并不显著;然而,添加缓冲剂时,1.0%体重/天的玉米使干物质采食量增加幅度最大。