Bush J A, Freeman D E, Kline K H, Merchen N R, Fahey G C
Department of Animal Sciences, University of Illinois, Urbana 61801, USA.
J Anim Sci. 2001 Jan;79(1):232-9. doi: 10.2527/2001.791232x.
Addition of fat to the diet of the equine is a popular method of increasing energy density of the diet while reducing feed intake. Reducing feed intake is of interest to race horse trainers because additional feed is seen as additional weight and, therefore, a hindrance to performance. Limited information is available regarding the interactions of fat with other dietary components, particularly fiber, in the equine digestive system. The effect of dietary fat on in vitro nutrient disappearance in equine cecal fluid was studied in Exp. 1 using a split-plot design within a 2 x 2 Latin square. Two ponies were fed alfalfa (ALF) alone or alfalfa plus 100 g/d corn oil. Five substrates were used to determine in vitro DM disappearance, OM disappearance, NDF disappearance, and total dietary fiber (TDF) disappearance. The substrates included: ALF, tall fescue (TF), red clover (RC), soybean hulls (SBH), and rolled oats (RO). Fat supplementation did not affect in vitro DM, OM, or NDF disappearance. Addition of fat to the diet increased (P < 0.05) the disappearance of NDF in RO. Among substrates, in vitro DM and OM disappearance were highest (P < 0.05) for RO, followed by SBH, ALF, RC, and TF. In vitro NDF and TDF disappearance were highest (P < 0.05) for SBH, followed by RO, ALF, RC, and TF. In Exp. 2, the effects of varying levels of fat on nutrient intake and total tract digestibility were examined using a 4 x 4 Latin square design. Four mature mares were fed a 60% forage-40% concentrate diet containing different concentrations of fat: 0% supplemental fat control (C); 5% supplemental corn oil (5% CO); 10% supplemental corn oil (10% CO); or 15% supplemental corn oil (15% CO). Treatment did not affect intake of the concentrate portion of the diet or CP, gross energy, or NDF intake. Mares consuming the C diet had the highest (P < 0.05) intake of alfalfa cubes, DM, and OM, followed by those on the 10, 5, and 15% CO treatments, respectively. Treatment did not affect nutrient digestibility. Mares consuming the 15% CO diet had the highest (P < 0.05) fat digestibility, whereas those consuming C had the lowest fat digestibility. Fat in the form of CO generally had little effect on in vitro and in vivo nutrient digestibilities in horses.
在马的日粮中添加脂肪是一种增加日粮能量密度同时减少采食量的常用方法。减少采食量受到赛马训练师的关注，因为额外的饲料被视为额外的体重，因此会对性能产生阻碍。关于脂肪与马消化系统中其他日粮成分（特别是纤维）之间相互作用的信息有限。在实验1中，采用2×2拉丁方内的裂区设计，研究了日粮脂肪对马盲肠液中体外养分消失的影响。给两匹小马单独饲喂苜蓿（ALF）或苜蓿加100克/天玉米油。使用五种底物来测定体外干物质消失率、有机物消失率、中性洗涤纤维消失率和总膳食纤维（TDF）消失率。底物包括：苜蓿、高羊茅（TF）、红三叶草（RC）、大豆皮（SBH）和燕麦片（RO）。添加脂肪不影响体外干物质、有机物或中性洗涤纤维的消失率。日粮中添加脂肪增加了（P<0.05）燕麦片中中性洗涤纤维的消失率。在底物中，燕麦片的体外干物质和有机物消失率最高（P<0.05），其次是大豆皮、苜蓿、红三叶草和高羊茅。大豆皮的体外中性洗涤纤维和总膳食纤维消失率最高（P<0.05），其次是燕麦片、苜蓿、红三叶草和高羊茅。在实验2中，采用4×4拉丁方设计研究了不同水平脂肪对养分摄入量和全消化道消化率的影响。给四匹成年母马饲喂含不同浓度脂肪的60%粗饲料-40%精饲料日粮：0%补充脂肪对照（C）；5%补充玉米油（5%CO）；10%补充玉米油（10%CO）；或15%补充玉米油（15%CO）。处理不影响日粮精料部分的摄入量或粗蛋白、总能或中性洗涤纤维摄入量。采食C日粮的母马苜蓿块、干物质和有机物摄入量最高（P<0.05），其次分别是采食10%、5%和15%CO处理的母马。处理不影响养分消化率。采食15%CO日粮的母马脂肪消化率最高（P<0.05），而采食C日粮的母马脂肪消化率最低。玉米油形式的脂肪一般对马的体外和体内养分消化率影响不大。
