Grummer R R
Diary Science Department, University of Wisconsin, Madison 53706.
J Dairy Sci. 1988 Jan;71(1):117-23. doi: 10.3168/jds.S0022-0302(88)79532-6.
Four rumen cannulated Holstein cows were used in a Latin square design to examine the effect of supplemental calcium salt of palm oil fatty acids (.68 kg/d) or prilled fat (.68 or .91 kg/d) on DM intake, rumen fermentation, and nutrient digestibility. Basal diet contained 45% concentrate, 27.5% alfalfa silage, and 27.5% corn silage (DM basis), and treatments were balanced for calcium. Dry matter intake was similar among treatments. Ruminal pH, total VFA, and molar percentage acetate and propionate were not affected by fat supplementation. Feeding prilled fat decreased slightly ruminal molar percentage butyrate. Forage DM and neutral detergent fiber disappearance from ruminally suspended dacron bags did not differ due to treatment. For unknown reasons, total tract apparent digestibility of DM and NDF was lower when cows received the low amount but not the high amount of prilled fat. Milk yield and fat percentage were not significantly affected by treatment. Milk protein was maintained during prilled fat supplementation but decreased .13% during calcium salt of palm oil fatty acid supplementation. Both fat supplements appeared inert in the rumen and did not markedly affect nutrient digestion when supplemented at 3.5% or less of the total ration DM.
选用4头安装有瘤胃瘘管的荷斯坦奶牛，采用拉丁方设计，研究添加棕榈油脂肪酸钙盐（0.68千克/天）或颗粒脂肪（0.68或0.91千克/天）对干物质采食量、瘤胃发酵和养分消化率的影响。基础日粮包含45%精料、27.5%苜蓿青贮和27.5%玉米青贮（以干物质计），各处理的钙含量均衡。各处理间干物质采食量相似。补充脂肪对瘤胃液pH值、总挥发性脂肪酸以及乙酸和丙酸的摩尔百分比没有影响。饲喂颗粒脂肪使瘤胃丁酸摩尔百分比略有下降。由于处理方式不同，瘤胃中悬挂的涤纶袋内牧草干物质和中性洗涤纤维的消失率没有差异。出于未知原因，奶牛摄入低量而非高量颗粒脂肪时，干物质和中性洗涤纤维的全肠道表观消化率较低。处理方式对产奶量和乳脂率没有显著影响。补充颗粒脂肪期间乳蛋白含量保持稳定，但补充棕榈油脂肪酸钙盐期间乳蛋白含量下降了0.13%。当两种脂肪补充料添加量占日粮干物质总量的3.5%或更低时，在瘤胃中似乎呈惰性，对养分消化没有明显影响。
