Burdick Sanchez Nicole C, Broadway Paul R, Carroll Jeffery A
Livestock Issues Research Unit, ARS, USDA, Lubbock, TX 79403, USA.
Animals (Basel). 2021 Feb 2;11(2):371. doi: 10.3390/ani11020371.
Nutritional supplementation has been used by livestock producers for many years in order to increase animal performance, improve animal health, and reduce negative effects associated with enteric and/or respiratory pathogens. Supplements such as yeast and yeast-based products have broad applications across many livestock production systems, including poultry, aquaculture, cattle, and swine and have been shown to benefit animal production at various stages. These benefits include improvement in milk production, weight gain and feed conversion, as well as immune function. Initial research into the mode of action for these effects has focused on stimulation of the immune system by the β-glucan fractions of yeast. However, emerging studies have revealed that some of the beneficial effects of yeast products may stem from altering metabolism, including the availability of glucose and fatty acids. These changes in metabolism, and potentially energy availability, may partially explain differences in immune function observed in yeast-supplemented livestock, as the energy demands of an activated immune system are extremely high. Thus, this paper explores the influence of yeast products on metabolism in cattle and swine, and how changes in metabolism and energy availability may contribute to improvements in immune function in supplemented animals.
多年来，畜牧生产者一直使用营养补充剂来提高动物生产性能、改善动物健康状况，并减少与肠道和/或呼吸道病原体相关的负面影响。酵母及酵母基产品等补充剂在许多畜牧生产系统中都有广泛应用，包括家禽、水产养殖、牛和猪，并且已证明在各个生产阶段都对动物生产有益。这些益处包括提高产奶量、体重增加和饲料转化率，以及增强免疫功能。对这些作用方式的初步研究集中在酵母的β-葡聚糖部分对免疫系统的刺激。然而，新出现的研究表明，酵母产品的一些有益作用可能源于代谢的改变，包括葡萄糖和脂肪酸的可用性。代谢的这些变化以及潜在的能量可用性，可能部分解释了在补充酵母的家畜中观察到的免疫功能差异，因为激活的免疫系统对能量的需求极高。因此，本文探讨了酵母产品对牛和猪代谢的影响，以及代谢和能量可用性的变化如何有助于提高补充动物的免疫功能。
