Bainbridge Melissa L, Egolf Emily, Barlow John W, Alvez Juan P, Roman Joe, Kraft Jana
The University of Vermont, Department of Animal and Veterinary Sciences, 570 Main St., Burlington, VT 05405, USA.
The University of Vermont, Center for Sustainable Agriculture, 23 Mansfield Ave., Burlington, VT 05405, USA.
Food Chem. 2017 Feb 15;217:750-755. doi: 10.1016/j.foodchem.2016.08.134. Epub 2016 Sep 1.
The demand for dairy products from grass-fed cows is driven, in part, by their more desirable fatty acid (FA) profile, containing more n-3 FA and conjugated linoleic acids (CLA) than conventionally produced dairy products. This study investigated the effects of pearl millet (PM) vs. cool-season pasture (CSP) on animal performance and milk FA in a grazing system. Eight Holstein dairy cows were used in a repeated measures design with four-week periods. Forage type had no effect on animal performance (estimated dry matter intake, milk production, fat, or protein). The contents of CLA and n-3 FA in a serving of whole milk (3.25% fat) increased when cows grazed CSP compared to PM. A serving of whole milk from cows grazing PM had a higher content of saturated FA and branched-chain FA. In conclusion, the contents of various bioactive FA were higher in milk fat of cows grazing a CSP compared to PM.
对草饲奶牛乳制品的需求,部分原因在于其更理想的脂肪酸(FA)组成,与传统生产的乳制品相比,含有更多的n-3脂肪酸和共轭亚油酸(CLA)。本研究调查了在放牧系统中,珍珠粟(PM)与冷季牧场(CSP)对动物生产性能和牛奶脂肪酸的影响。采用重复测量设计,为期四周,使用了八头荷斯坦奶牛。饲草类型对动物生产性能(估计干物质摄入量、产奶量、脂肪或蛋白质)没有影响。与珍珠粟相比,奶牛放牧冷季牧场时,一份全脂牛奶(含3.25%脂肪)中CLA和n-3脂肪酸的含量增加。放牧珍珠粟的奶牛所产全脂牛奶中饱和脂肪酸和支链脂肪酸的含量更高。总之,与珍珠粟相比,放牧冷季牧场的奶牛乳脂中各种生物活性脂肪酸的含量更高。