Chase L E
Department of Animal Science, Cornell University, Ithaca, NY 14853.
J Dairy Sci. 1993 Oct;76(10):3287-93. doi: 10.3168/jds.S0022-0302(93)77665-1.
Herd average milk production continues to increase in the US. Average milk production in Holstein herds enrolled in DHI testing programs surpassed 9000 kg in some states in 1991. Individual dairy herds have produced > 14,000 kg per cow per lactation. The upper limit for milk production per cow continues to increase. A challenge exists in developing nutrition programs for these herds. The goal is to attain efficient and profitable levels of milk production while maintaining herd health and reproductive performance. Evaluation of rations currently fed to high producing herds indicate that these rations are consistent with current nutrient requirement guidelines. Many high producing herds have average DMI > 4% of BW. Ration formulation principles and nutrient requirements used in development of feeding programs for high producing herds are similar to methods already in use. Optimizing DMI, optimizing rumen fermentation, and providing supplemental nutrients are key factors in meeting tissue nutrient demands in this formulation process.
美国牛群的平均产奶量持续增长。1991年，参加DHI检测项目的荷斯坦牛群在某些州的平均产奶量超过了9000千克。个别奶牛场每头奶牛每个泌乳期的产奶量超过了14000千克。每头奶牛的产奶量上限持续提高。为这些牛群制定营养方案面临挑战。目标是在维持牛群健康和繁殖性能的同时，实现高效且盈利的产奶水平。对目前高产牛群所喂日粮的评估表明，这些日粮符合当前的营养需求指南。许多高产牛群的平均干物质采食量超过体重的4%。为高产牛群制定饲养方案时所采用的日粮配方原则和营养需求与已使用的方法类似。在这个配方过程中，优化干物质采食量、优化瘤胃发酵以及提供补充营养是满足组织营养需求的关键因素。
