Christensen R A, Drackley J K, LaCount D W, Clark J H
Department of Animal Sciences, University of Illinois, Urbana 61801.
J Dairy Sci. 1994 Apr;77(4):1052-69. doi: 10.3168/jds.S0022-0302(94)77041-7.
Five Holstein cows were utilized in a Latin square design to determine the effects of postruminal profile of fatty acids on DMI, milk yield and composition, nutrient digestibilities, and metabolites in blood. Treatments were abomasal infusions of 1) control, 169 to 180 g/d of meat solubles; 2) control plus 450 g/d of mostly saturated fatty acids; 3) canola fatty acids; 4) soybean fatty acids; or 5) sunflower fatty acids. Infusion of fatty acids decreased intakes of DM, CP, and gross energy; yields of milk, FCM, SNF, total solids, CP, NPN, true protein, whey protein, and casein; and percentages of SNF, CP, NPN, true protein, and casein in milk. Cows infused with mostly saturated fatty acids consumed more CP and digestible energy; yielded more milk, FCM, fat, SNF, total solids, CP, true protein, and casein; and had greater percentages of SNF and total solids in milk than cows infused with unsaturated fatty acids. Milk fatty acids reflected the profile of the infused fatty acid mixture. Ruminal characteristics and apparent digestibilities of DM, NDF, energy, and fatty acids generally were not different among treatments. The profile of fatty acids reaching the small intestine may influence responses when supplemental fats are fed to lactating dairy cows.
选用5头荷斯坦奶牛采用拉丁方设计，以确定瘤胃后脂肪酸组成对干物质采食量（DMI）、产奶量及乳成分、养分消化率和血液代谢产物的影响。处理方式为真胃灌注：1）对照，169至180克/天的肉渣；2）对照加450克/天主要为饱和脂肪酸；3）菜籽油脂肪酸；4）大豆脂肪酸；或5）向日葵脂肪酸。脂肪酸灌注降低了干物质、粗蛋白和总能的摄入量；降低了牛奶、校正奶、非脂固形物、总固形物、粗蛋白、非蛋白氮、真蛋白、乳清蛋白和酪蛋白的产量；以及牛奶中非脂固形物、粗蛋白、非蛋白氮、真蛋白和酪蛋白的百分比。灌注主要为饱和脂肪酸的奶牛比灌注不饱和脂肪酸的奶牛消耗更多的粗蛋白和可消化能量；产奶量、校正奶、脂肪、非脂固形物、总固形物、粗蛋白、真蛋白和酪蛋白更多；且牛奶中非脂固形物和总固形物的百分比更高。牛奶脂肪酸反映了灌注脂肪酸混合物的组成。各处理间瘤胃特性以及干物质、中性洗涤纤维、能量和脂肪酸的表观消化率一般无差异。给泌乳奶牛补饲脂肪时，到达小肠的脂肪酸组成可能会影响奶牛的反应。
