Dhiman T R, Helmink E D, McMahon D J, Fife R L, Pariza M W
Utah State University, Logan 84322-4815, USA.
J Dairy Sci. 1999 Feb;82(2):412-9. doi: 10.3168/jds.S0022-0302(99)75247-1.
Extruded oilseeds were fed to 24 dairy cows to study the influence on the conjugated linoleic acid content of milk and cheese. Cows were fed one of three diets that contained forage and grain in a ratio of 47:53. A control diet containing 13.5% soybean meal was compared with diets containing 12% full fat extruded soybeans or 12% full fat extruded cottonseed. The control, extruded soybean, and extruded cottonseed diets contained 2.73, 4.89, and 4.56% fatty acids, respectively. Measurements were made during the last 5 wk of the 8-wk experiment. The DM intakes and 3.5% fat-corrected milk yields were higher for cows fed the extruded soybean and extruded cottonseed diets than for cows fed the control diet. A tendency for lower fat and protein contents in the milk of cows fed the extruded soybean and extruded cottonseed diets was detected. Most of the C18 fatty acids were increased in the milk and cheese when extruded soybeans and cottonseeds were fed. The conjugated linoleic acid content in milk and cheese increased a mean of 109% when full fat extruded soybeans were fed and increased 77% when cottonseeds were fed compared with the conjugated linoleic acid content when the control diet was fed. Processing the milk into cheese did not alter the conjugated linoleic acid content. The conjugated linoleic acid content of milk and cheese can be increased by the inclusion of full fat extruded soybeans and full fat extruded cottonseeds in the diets of dairy cows.
将挤压膨化的油籽喂给24头奶牛，以研究其对牛奶和奶酪中共轭亚油酸含量的影响。奶牛被饲喂三种日粮中的一种，这些日粮中粗饲料和谷物的比例为47:53。将含有13.5%豆粕的对照日粮与含有12%全脂挤压膨化大豆或12%全脂挤压膨化棉籽的日粮进行比较。对照日粮、挤压膨化大豆日粮和挤压膨化棉籽日粮中脂肪酸含量分别为2.73%、4.89%和4.56%。在为期8周试验的最后5周进行测定。饲喂挤压膨化大豆日粮和挤压膨化棉籽日粮的奶牛干物质采食量和3.5%乳脂校正乳产量高于饲喂对照日粮的奶牛。检测到饲喂挤压膨化大豆日粮和挤压膨化棉籽日粮的奶牛所产牛奶中脂肪和蛋白质含量有降低的趋势。饲喂挤压膨化大豆和棉籽时，牛奶和奶酪中的大多数C18脂肪酸含量增加。与饲喂对照日粮时的共轭亚油酸含量相比，饲喂全脂挤压膨化大豆时牛奶和奶酪中共轭亚油酸含量平均增加109%，饲喂棉籽时增加77%。将牛奶加工成奶酪不会改变共轭亚油酸含量。在奶牛日粮中添加全脂挤压膨化大豆和全脂挤压膨化棉籽可提高牛奶和奶酪中共轭亚油酸含量。
