USDA-ARS-National Laboratory for Agriculture and the Environment, Ames, IA 50011, USA.
J Anim Sci Biotechnol. 2013 Mar 15;4(1):11. doi: 10.1186/2049-1891-4-11.
Application of feed processing methods and use of exogenous feed additives in an effort to improve nutrient digestibility of plant-based feed ingredients for swine has been studied for decades. The following review will discuss several of these topics, including: fiber characterization, impact of dietary fiber on gastrointestinal physiology, energy, and nutrient digestibility, mechanical processing of feed on fiber and energy digestibility, and the use of exogenous enzymes in diets fed to growing pigs. Taken together, the diversity and concentration of chemical characteristics that exists among plant-based feed ingredients, as well as interactions among constituents within feed ingredients and diets, suggests that improvements in nutrient digestibility and pig performance from mechanical processing or adding exogenous enzymes to diets fed to swine depends on a better understanding of these characteristics, but also relating enzyme activity to targeted substrates. It may be that an enzyme must not only match a target substrate(s), but there may also need to be a 'cocktail' of enzymes to effectively breakdown the complex matrixes of fibrous carbohydrates, such that the negative impact of these compounds on nutrient digestibility or voluntary feed intake are alleviated. With the inverse relationship between fiber content and energy digestibility being well described for several feed ingredients, it is only logical that development of processing techniques or enzymes that degrade fiber, and thereby improve energy digestibility or voluntary feed intake, will be both metabolically and economically beneficial to pork production.
几十年来，人们一直在研究饲料加工方法的应用和外源饲料添加剂的使用，以提高猪用植物性饲料原料的营养消化率。以下综述将讨论其中的几个主题，包括：纤维特性、膳食纤维对胃肠道生理学、能量和养分消化率的影响、饲料的机械加工对纤维和能量消化率的影响，以及在生长猪日粮中使用外源酶。总之，植物性饲料原料之间存在的化学特性的多样性和浓度，以及饲料原料和日粮内成分之间的相互作用，表明通过机械加工或向猪日粮中添加外源酶来提高养分消化率和猪的生产性能，不仅取决于对这些特性的更好理解，还取决于将酶活性与目标底物相关联。可能是一种酶不仅必须与目标底物（s）匹配，而且还可能需要“鸡尾酒”酶来有效地分解纤维碳水化合物的复杂基质，从而减轻这些化合物对养分消化率或自愿采食量的负面影响。由于几种饲料原料的纤维含量与能量消化率之间存在着反比关系，因此开发能够降解纤维从而提高能量消化率或自愿采食量的加工技术或酶，在代谢和经济上都有利于猪肉生产，这是合乎逻辑的。
