外源酶制剂在反刍动物上的应用与展望

Application and Outlook of Exogenous Enzymes in Ruminants

反刍动物能够将人类不能利用的粗饲料转化为优质蛋白质——肉和奶,这对农业以及人类社会有着重要意义。但是这种转化效率与植物细胞壁的消化率有重要关系,目前植物性原料消化率较低,影响了转化效率。在反刍动物饲粮中补充外源酶制剂具有提高植物纤维消化的潜力,从而提高饲粮的利用效率。本文总结了外源酶制剂应用现状、作用模式以及发展方向,认为目前外源酶制剂在反刍动物应用上有积极的结果,也存在效果不明显的报道,这可能与酶谱、添加水平、添加方式、底物类型以及宿主的生产水平等方面有关。同时阐述了外源酶制剂是在饲喂前、瘤胃中、瘤胃后的不同环境中起到作用,但详细机制还需要继续深入探究。综上所述,尽管酶制剂应用还存在一些问题,以提高饲料消化率为目标的酶制剂仍将会是反刍动物添加剂发展的一个重要方向。

Ruminants can convert forage that human can＇ t use directly to high quality protein-meat and milk,which is important to agriculture and human society.However,the conversion efficiency is dependent on digestibility of plant cell walls.The digestibility of plant material is low at present.It is potential to improve plant fiber digestibility that supplementing ruminant diets with exogenous enzymes,and thus improve the efficiency of feed utilization.This review summarized the application status,modes of action,and development directions of exogenous enzymes.The effects of exogenous enzymes in ruminants had variability,which might be due to enzyme array,addition level,addition mode,substrate type and host productive level.Exogenous enzymes acted in different environments,such as before feeding,in rumen and post-rumen,however,the exactly mechanism needed more investigation.In general,exogenous enzymes that used to enhance the feed digestibility would be one of the most important ruminant additives in the future,though they had variability at present.