Nutritional and anti-nutritional characters and rumen degradability of dry matter and nitrogen for some multipurpose tree species with potential for agroforestry in Zimbabwe

Abstract

In a preliminary study on the nutritional value of seven multipurpose trees (MPTs), currently showing potential use in agroforestry systems in Zimbabwe, crude protein values ranged from 189 g kg −1 DM in Flemingia macrophylla to 292 g kg −1 DM in Acacia angustissima. Acid detergent fibre (ADF) content was low especially in Sesbania sesban (99 g kg −1 DM), while ADF contents in Flemingia macrophylla (277 g kg −1 DM) and Cajanus cajan (255 g kg −1 DM) were the highest. The MPTs had ash contents ranging from 58 g kg −1 DM in Flemingia macrophylla and Cajanus cajan to 95 g kg −1 DM in Sesbania sesban. MPTs with detectable amounts of condensed tannins were Calliandra calothyrsus (17.9 g kg −1 DM), A. angustissima (10.3 g kg −1 DM) and Flemingia macrophylla (3.4 g kg −1 DM). These MPTs were poorly degraded in the rumen compared to the other four species. The presence of condensed tannins could lower their potential as ruminant feeds.