摘要
Active dry yeasts (ADYs) are increasingly used in ruminant nutrition as feed additives to improve feed efficiency and performance and, at the same time, to prevent health disorders. They are particularly useful in high-producing ruminants whose digestive microbial balance can be altered by high-dietary energy input. As ADYs can survive and remain metabolically active in the gut, they can exert probiotic effects by interacting with the autochthonous microbial species responsible for feed digestion. Up to now, the most consistent positive effects of ADYs have been reported on rumen microbial activity in young ruminants, stabilisation of rumen pH and prevention of acidosis, as well as stimulation of growth and activity of fibre-degrading bacteria. Effects of ADYs vary depending on biotic factors such as the strain of yeast and its viability, but also on abiotic factors, such as the nature of the diet or animal management. It is important to better understand the way by which yeasts can act on rumen microorganisms in order to direct selection of new generation ADYs. The objectives of this paper are to review the most important findings on effects of ADYs in the rumen, to describe identified modes of action, and to provide thoughts for further strain selection and applications in ruminant nutrition.
摘要译文
活性干酵母（ADYs）在反刍动物营养中越来越多地用作饲料添加剂，以改善饲料效率和性能，同时预防健康紊乱。它们在高产反刍动物中特别有用，其消化微生物平衡可以通过高膳食能量输入而改变。由于ADY可以在肠道中存活并保持代谢活跃，它们可以通过与负责饲料消化的本土微生物物质相互作用来发挥益生菌作用。到现在，已报道ADY的最一致的积极作用是对年轻反刍动物的瘤胃微生物活性，稳定瘤胃pH和预防酸中毒，以及刺激纤维降解细菌的生长和活性。 ADY的影响取决于生物因素，例如酵母的菌株及其生存力，还取决于非生物因子，如饮食或动物管理的性质。更好地了解酵母对瘤胃微生物的作用方式，以指导新一代ADYs的选择。本文的目的是回顾关于ADY在瘤胃中的影响的最重要的发现，描述确定的作用模式，为进一步筛选和应用反刍动物营养提供思路。
F. Chaucheyras-Durand[a][b]; N.D. Walker[a][b]; A. Bach[c][d]. Effects of active dry yeasts on the rumen microbial ecosystem: Past, present and future ☆[J]. Animal Feed Science and Technology, 2008,145(1-4): 5–26