Tannin on non-degradable digestible protein from proteic sources in cattle rumen

ABSTRACT. Several tannins at different inclusion levels of protein-rich food and water addition on the amount of rumen undegradable protein (RUP) and digestible RUP (RUPd) in the rumen were evaluated. Sixty treatments were analyzed, namely: three mixtures of tannin (with different concentrations of hydrolysable and condensed tannins) were added at four different amounts (0, 1, 2.5 and 5%) in three protein foods (soybean meal, whole soybean meal and peanut meal) with and without moisture. Samples were incubated in cattle, via rumen cannula, in triplicate, to quantify rumen degraded protein (RDP), rumen undegradable protein (RUP) and digestible RUP (RUPd). Divergence in protein nutritional rate, based on discriminating variables among the groups, was estimated by cluster analysis. Increase in RUPd of treatments required soybean meal with 2.5% tannin, with 85% of condensed tannins and 15% hydrolysable tannins, in an aqueous medium. The inclusion of tannin is recommended to test in in vivo evaluations for productivity increase and inclusion level used.

摘要
本研究评估了添加于高蛋白饲料原料中的不同水平单宁，以及水分添加量，对瘤胃内瘤胃非降解蛋白（rumen undegradable protein, RUP）及其可消化组分（digestible RUP, RUPd）含量的影响。
本实验共设置60个处理组：将3种水解单宁与缩合单宁配比各不相同的单宁混合物，以0、1、2.5、5%四种添加量，分别添加至3种高蛋白饲料原料（豆粕（soybean meal）、全脂豆粕（whole soybean meal）、花生粕（peanut meal））中，每组均设置含水分与不含水分两个平行组别。采用瘤胃瘘管（rumen cannula）技术，将样品植入肉牛瘤胃内进行培养，每组设3个重复，以定量测定瘤胃降解蛋白（rumen degraded protein, RDP）、瘤胃非降解蛋白（RUP）及其可消化组分（RUPd）的含量。基于组间判别变量的蛋白质营养率差异，通过聚类分析（cluster analysis）进行估算。
可提升处理组RUPd含量的最优条件为：含水环境下，在豆粕中添加2.5%的单宁混合物，该混合物含85%缩合单宁与15%水解单宁。建议后续开展体内评价试验，以探究单宁添加对生产性能的提升效果，并明确其适宜添加水平。