Department of Animal Science, Oklahoma State University, Stillwater, OK, USA.
J Anim Sci. 2012 Jun;90(6):2014-25. doi: 10.2527/jas.2011-4152.
Three experiments were conducted to evaluate supplementation of dried distillers grains with solubles (DGS) to spring-calving beef cows (n = 120; 541 kg of initial BW; 5.1 initial BCS) consuming low-quality forage during late gestation and early lactation. Supplemental treatments included (DM basis) 1) 0.77 kg/d DGS (DGSL); 2) 1.54 kg/d DGS (DGSI); 3) 2.31 kg/d DGS (DGSH); 4) 1.54 kg/d of a blend of 49% wheat middlings and 51% cottonseed meal (POS); and 5) 0.23 kg/d of a cottonseed hull-based pellet (NEG). Feeding rate and CP intake were similar for DGSI and POS. In Exp. 1, cows were individually fed 3 d/wk until calving and 4 d/wk during lactation; total supplementation period was 119 d, encompassing 106 d of gestation and 13 d of lactation. Tall-grass prairie hay (5.6% CP, 50% TDN, 73% NDF; DM basis) was fed for ad libitum intake throughout the supplementation period. Change in cow BW and BCS during gestation was similar for DGSI and POS (-5.0 kg, P = 0.61 and -0.13, P = 0.25, respectively) and linearly increased with increasing DGS level (P < 0.01). Likewise, during the 119-d supplementation period, BW and BCS change were similar for DGSI and POS (-72 kg, P = 0.22 and -0.60, P = 0.10) and increased linearly with respect to increasing DGS (P < 0.01). The percentage of cows exhibiting luteal activity at the beginning of breeding season (56%, P = 0.31), AI conception rate (57%, P = 0.62), or pregnancy rate at weaning (88%, P = 0.74) were not influenced by supplementation. In Exp. 2, 30 cows from a separate herd were used to evaluate the effect of DGS on hay intake and digestion. Supplementation improved all digestibility measures compared with NEG. Hay intake was not influenced by DGS (P > 0.10); digestibility of NDF, ADF, CP, and fat linearly increased with increasing DGS. In Exp. 3, milk production and composition were determined for cows (n = 16/treatment) of similar days postpartum from Exp. 1. Daily milk production was not influenced by supplementation (6.3 kg/d, P = 0.25). Milk fat (2.1%) and lactose (5.0%) were not different (P > 0.10). Milk protein linearly increased as DGS increased (P < 0.05) and was greater for DGSI compared with POS. Similar cow performance was achieved when cows were fed DGS at the same rate and level of CP as a traditional cottonseed meal-based supplement. Increasing amounts of DGS did not negatively influence forage intake or diet digestibility.
进行了三项实验来评估在妊娠后期和泌乳早期给食用低质量饲草的春季产奶牛（n = 120；初始体重为 541 公斤；初始体况评分为 5.1）补充干酒糟及其可溶物（DGS）。补充处理包括（DM 基础）1）0.77 公斤/天 DGS（DGSL）；2）1.54 公斤/天 DGS（DGSI）；3）2.31 公斤/天 DGS（DGSH）；4）1.54 公斤/天的 49%小麦麸皮和 51%棉籽粉混合物（POS）；和 5）0.23 公斤/天的棉籽壳颗粒（NEG）。DGSI 和 POS 的采食量和 CP 摄入量相似。在实验 1 中，奶牛每周 3 天接受个体喂养，直到分娩，哺乳期 4 天/周；总补充期为 119 天，包括 106 天妊娠和 13 天泌乳。高草草原干草（5.6% CP、50% TDN、73% NDF；DM 基础）在整个补充期内自由采食。DGSI 和 POS 在妊娠期间的奶牛体重和体况评分变化相似（-5.0 公斤，P = 0.61 和-0.13，P = 0.25），并且随着 DGS 水平的增加呈线性增加（P < 0.01）。同样，在 119 天的补充期内，DGSI 和 POS 的奶牛体重和体况评分变化相似（-72 公斤，P = 0.22 和-0.60，P = 0.10），并且随着 DGS 的增加呈线性增加（P < 0.01）。在繁殖季节开始时表现出黄体活动的奶牛比例（56%，P = 0.31）、AI 受胎率（57%，P = 0.62）或断奶时的妊娠率（88%，P = 0.74）不受补充的影响。在实验 2 中，使用来自单独牛群的 30 头奶牛来评估 DGS 对干草采食量和消化的影响。与 NEG 相比，补充提高了所有消化率测量值。DGS 对干草采食量没有影响（P > 0.10）；NDF、ADF、CP 和脂肪的消化率随 DGS 的增加呈线性增加。在实验 3 中，对来自实验 1 的类似产后天数的奶牛（n = 16/处理）进行了牛奶生产和组成的测定。补充对牛奶日产量没有影响（6.3 公斤/天，P = 0.25）。牛奶脂肪（2.1%）和乳糖（5.0%）没有差异（P > 0.10）。牛奶蛋白随 DGS 的增加呈线性增加（P < 0.05），并且与 POS 相比，DGSI 更高。当奶牛以与传统棉籽粉基补充剂相同的速度和 CP 水平补充 DGS 时，实现了相似的奶牛性能。增加 DGS 的量不会对饲草采食量或日粮消化率产生负面影响。
