Effects of level and source of carbohydrate and level of degradable intake protein on intake and digestion of low-quality tallgrass-prairie hay by beef steers.
Effects of level and source of carbohydrate and level of degradable intake protein on intake and digestion of low-quality tallgrass-prairie hay by beef steers.
复制标题
碳水化合物水平和来源以及可降解摄入蛋白水平对肉牛摄入和消化低品质高草草原干草的影响。
DOI：
10.2527/1999.77102846x
复制
发表时间：
1999
影响因子：
3.3
通讯作者：
D. Johnson
中科院分区：
文献类型：
--
作者：
J. Heldt;R. Cochran;C. Mathis;B. C. Woods;K. Olson;E. Titgemeyer;T. Nagaraja;E. Vanzant;D. Johnson
采用不完全拉丁方法，对13头263 kg瘤胃瘘管阉牛进行13个处理和4个时期的试验，研究了不同水平和来源的补充碳水化合物（CHO）和可降解蛋白质（DIP）对低品质高草草原干草利用率的影响。牛可自由采食饲料（5.7% CP、2.6% DIP和74.9% NDF）。补充处理被塑造为2x 3x 2析因排列加阴性对照（NC;无补充）。这些因素包括两个DIP水平（0.031和0.122%BW）和三种CHO来源（淀粉、葡萄糖和纤维），在每个DIP补充水平内以两个水平（0.15和0.30%BW）饲喂。补充饲料OM摄入量（FOMI）的效果取决于（P<0.01）CHO的水平和来源以及DIP的水平。当DIP低，饲料，总，可消化OM摄入量一般大于淀粉处理比非淀粉处理。然而，当DIP水平高时，非淀粉的摄入量更大（即，纤维和葡萄糖）治疗。一般来说，当提供更多的补充CHO时，FOMI降低（P<0.01）。补充通常增加纤维消化，但反应是依赖于（P<0.01）的水平和来源的CHO和DIP的水平。一般来说，补充低水平的CHO改善NDF消化（NDFD）。然而，补充高水平的CHO降低NDFD，除了纤维在高水平的DIP。有机物的消化率随着饲料添加量的增加而增加，但增加CHO的效果取决于CHO的来源和DIP的水平（P<0.01）。不同添加水平对瘤胃pH、NH3-N、有机酸总量及其相对比例有显著影响。总之，补充DIP提高了低质量饲料的使用，但是，补充CHO对低质量饲料使用的影响取决于提供的CHO的来源和水平，以及DIP的水平。
Ruminally fistulated steers (n = 13; 263 kg) were used in an incomplete Latin square with 13 treatments and four periods to evaluate the effects of level and source of supplemental carbohydrate (CHO) and level of degradable intake protein (DIP) on the utilization of low-quality, tallgrass-prairie hay. Steers were given ad libitum access to forage (5.7% CP, 2.6% DIP, and 74.9% NDF). The supplementation treatments were fashioned as a 2x3x2 factorial arrangement plus a negative control (NC; no supplement). The factors included two DIP levels (.031 and .122% BW) and three CHO sources (starch, glucose, and fiber) fed at two levels (.15 and .30% BW) within each level of DIP supplementation. The effect of supplementation on forage OM intake (FOMI) was dependent (P<.01) on level and source of CHO and level of DIP fed. When DIP was low, forage, total, and digestible OM intakes were generally greater for the starch treatment than for the nonstarch treatments. However, when the DIP level was high, intakes were greater for the nonstarch (i.e., fiber and glucose) treatments. Generally, FOMI decreased (P<.01) when more supplemental CHO was provided. Supplementation typically increased fiber digestion, but the response was dependent (P<.01) on level and source of CHO and level of DIP. Generally, supplements with low levels of CHO improved NDF digestion (NDFD). However, supplements with the high level of CHO decreased NDFD, except for fiber at the high level of DIP. Organic matter digestion was increased by supplementation, but the impact of increasing CHO was dependent (P<.01) on source of CHO and level of DIP. Supplementation treatments had significant impact on ruminal pH, NH3 N, and the total concentration of organic acids as well as their relative proportions. In conclusion, supplemental DIP enhanced the use of low-quality forage; however, the impact of supplemental CHO on low-quality forage use was dependent on source and level of CHO offered, as well as the level of DIP provided.