Ritz Kathryn E, Heins Bradley J, Moon Roger D, Sheaffer Craig C, Weyers Sharon L
West Central Research and Outreach Center, University of Minnesota, Morris, MN 56267, USA.
Department of Entomology, University of Minnesota, St. Paul, MN 55108, USA.
Animals (Basel). 2021 Jan 21;11(2):264. doi: 10.3390/ani11020264.
Organic dairy cows were used to evaluate the effect of two organic pasture production systems (temperate grass species and warm-season annual grasses and cool-season annuals compared with temperate grasses only) across two grazing seasons (May to October of 2014 and 2015) on milk production, milk components (fat, protein, milk urea nitrogen (MUN), somatic cell score (SCS)), body weight, body condition score (BCS), and activity and rumination (min/day). Cows were assigned to two pasture systems across the grazing season at an organic research dairy in Morris, Minnesota. Pasture System 1 was cool-season perennials (CSP) and Pasture System 2 was a combination of System 1 and warm-season grasses and cool-season annuals. System 1 and System 2 cows had similar milk production (14.7 and 14.8 kg d), fat percentage (3.92% vs. 3.80%), protein percentage (3.21% vs. 3.17%), MUN (12.5 and 11.5 mg dL), and SCS (4.05 and 4.07), respectively. Cows in System 1 had greater daily rumination (530 min/day) compared to cows in System 2 (470 min/day). In summary, warm-season annual grasses may be incorporated into grazing systems for pastured dairy cattle.
使用有机奶牛来评估两种有机牧场生产系统（温带草种、暖季一年生禾本科植物和冷季一年生植物与仅使用温带草种相比）在两个放牧季节（2014年和2015年5月至10月）对牛奶产量、牛奶成分（脂肪、蛋白质、牛奶尿素氮（MUN）、体细胞评分（SCS））、体重、体况评分（BCS）以及活动和反刍（分钟/天）的影响。奶牛被分配到明尼苏达州莫里斯市一家有机研究奶牛场的两个牧场系统中度过放牧季节。牧场系统1是冷季多年生植物（CSP），牧场系统2是系统1与暖季草和冷季一年生植物的组合。系统1和系统2的奶牛分别具有相似的牛奶产量（14.7和14.8千克/天）、脂肪百分比（3.92%对3.80%）、蛋白质百分比（3.21%对3.17%）、MUN（12.5和11.5毫克/分升）和SCS（4.05和4.07）。与系统2的奶牛（470分钟/天）相比，系统1的奶牛每天反刍时间更长（530分钟/天）。总之，暖季一年生禾本科植物可纳入放牧奶牛的放牧系统中。
