Comparative Nutritional Profiles and Fermentation Characteristics of Selected Tropical Legumes Subjected to Intensive Coppicing

Abstract

This study evaluates the nutritional profiles and fermentation characteristics of three selected tropical legumes, Flemingia macrophylla, Indigofera zollingeriana, and Gliricidia sepium, from fresh states through post-ensiled fermentation under a repeated coppicing regime. A Randomized Complete Block Design was employed across four three-month coppicing periods. Samples were evaluated for DM, CP, EE, ash, NDF, ADF, GE, and silage pH and temperature. Forages were ensiled for 21 days with a 5% molasses additive. The analysis was done through ANOVA and Linear Mixed Model using R software. Post hoc Tukey’s HSD for significant differences (α = 0.05). Repeated coppicing reduced pre-ensiled DM across all species (p<0.0001), reflecting progressive succulence in late-period regrowths. Increasing defoliation increased CP content in I. zollingeriana (p=0.0121) and G. sepium (p<0.0001) through maximization of leaf-to-stem ratios, while F. macrophylla had low initial CP levels and accumulated NDF (p=0.0035). In the post-ensiling period, G. sepium maintained a very stable pH level of 4.30 in its silage in the third phase (p<0.0001), which indicates almost perfect homofermentation. Indigofera zollingeriana had moderate silage acidification (pH 5.56-6.64) and underwent considerable proteolysis (CP loss: 10.50%), although acid hydrolysis of NDF brought down NDF content to 28.65%. The pH value in F. macrophylla did not show any steep drop (4.75-6.11) because of high buffering capacity. However, it was completely stabilized in terms of temperature to avoid aerobic spoilage. Gliricidia sepium produced the most chemically stable and easily digestible silage, thereby making it an ideal forage for tropical ruminants. A coppicing period of 90 days, before ensiling with wilting at a dry matter level of 30%, and addition of 5% molasses are suggested.