Krysl L J, Branine M E, Galyean M L, Estell R E, Hoefler W C
J Anim Sci. 1987 Apr;64(4):1178-88. doi: 10.2527/jas1987.6441178x.
To determine the influence of protein supplementation on intake and fermentation of low-quality hay, six ruminal- and cecal-cannulated Rambouillet ewes (avg wt 43.6 kg) in a crossover design were given ad libitum access to prairie hay with or without 80 g of cottonseed meal (CSM) X head-1 X d-1. Voluntary hay intake was measured the last 7 d of each 18-d period. Ruminal, cecal and blood samples were collected at 0, 1 (except cecal), 3, 6, 9, 12, 15, 18, 21 and 24 h post-supplementation on d 14 of each period to measure fluid dilution rate, fermentation characteristics and serum concentrations of insulin and growth hormone. An intraruminal dose of Yb-labeled hay, followed by fecal sampling on d 15 through 18, was used to measure particulate passage rate. Voluntary intake of prairie hay was increased (P less than .04) from 23.7 to 28.3 g/kg of body weight by CSM supplementation. Particulate passage rate constants did not differ (P greater than .15) between supplemented (3.76%/h) and control (3.72%/h) ewes, and total mean retention time was not altered (P greater than .15) by CSM supplementation. Ruminal retention time of particulates did not differ (P greater than .15) between treatments; however, intestinal transit time was faster (P less than .03; 18.1 vs 22.6 h) in supplemented than in control ewes. Estimated gastrointestinal dry matter fill was greater (P less than .05; 14.3 vs 12.9 g/kg body weight) in supplemented ewes. Ruminal fluid volume did not differ (P greater than .15) between treatments; however, supplemented ewes tended to have faster fluid dilution rates (P less than .14) and fluid outflow rates (P less than .11) than control ewes. Cecal fluid volume, dilution rate and outflow rate did not differ (P greater than .15) between groups. Ruminal and cecal pH and total volatile fatty acids were similar between treatments. Similarly, cottonseed meal supplementation did not affect (P greater than .15) ruminal or cecal ammonia concentrations. Molar proportions of ruminal and cecal individual fatty acids were not affected (P greater than .15) by CSM supplementation. Feeding cottonseed meal increased (P less than .05) serum insulin, decreased (P less than .07) serum growth hormone and increased (P less than .06) serum free fatty acids, but did not influence (P greater than .15) either serum urea N or glucose concentrations. Cottonseed meal supplementation in ewes fed prairie hay caused increased hay intake but had minimal effects on ruminal and cecal fermentation.
为了确定补充蛋白质对低质量干草采食量和发酵的影响，采用交叉设计，给6只装有瘤胃和盲肠瘘管的兰布耶母羊（平均体重43.6千克）随意提供含或不含80克棉籽粕（CSM）/头/天的草原干草。在每个18天周期的最后7天测量干草的随意采食量。在每个周期的第14天补充饲料后0、1（盲肠样本除外）、3、6、9、12、15、18、21和24小时采集瘤胃、盲肠和血液样本，以测量液体稀释率、发酵特性以及胰岛素和生长激素的血清浓度。瘤胃内注射镱标记的干草，然后在第15至18天采集粪便样本，用于测量颗粒通过率。补充CSM使草原干草的随意采食量从23.7克/千克体重增加到28.3克/千克体重（P<0.04）。补充组（3.76%/小时）和对照组（3.72%/小时）母羊的颗粒通过率常数没有差异（P>0.15），补充CSM对总平均滞留时间也没有影响（P>0.15）。各处理间颗粒的瘤胃滞留时间没有差异（P>0.15）；然而，补充组母羊的肠道通过时间比对照组更快（P<0.03；18.1小时对22.6小时）。补充组母羊的估计胃肠道干物质充盈量更大（P<0.05；14.3克/千克体重对12.9克/千克体重）。各处理间瘤胃液体积没有差异（P>0.15）；然而，补充组母羊的液体稀释率（P<0.14）和液体流出率（P<0.11）往往比对照组更快。两组间盲肠液体积、稀释率和流出率没有差异（P>0.15）。各处理间瘤胃和盲肠的pH值以及总挥发性脂肪酸相似。同样，补充棉籽粕对瘤胃或盲肠氨浓度没有影响（P>0.15）。补充CSM对瘤胃和盲肠中各脂肪酸的摩尔比例没有影响（P>0.15）。饲喂棉籽粕使血清胰岛素增加（P<0.05），血清生长激素降低（P<0.07），血清游离脂肪酸增加（P<0.06），但对血清尿素氮或葡萄糖浓度没有影响（P>0.15）。给采食草原干草的母羊补充棉籽粕会增加干草采食量，但对瘤胃和盲肠发酵的影响最小。
