Effect of harvesting interval on biomass yield and nutritive value of five tropical forage legumes (Aeschynomene histrix ‘BRA 9690’, Canavalia brasiliensis ‘CIAT 17009’, Stylosanthes guianensis ‘CIAT 184’ and ‘Composite’ and Vigna unguiculata ‘CIAT 1088‐4’) in Lao PDR

Abstract

AbstractForage legumes have the potential to provide high quality feed to small land‐holder farmers’ swine production, but forage management schemes that ensure both quantity and suitable quality as a swine feed are needed. Five forage legumes (aeschynomene [Aeschynomene histrix ‘BRA 9690’], canavalia [Canavalia brasiliensis ‘CIAT 17009’], stylo ‘CIAT 184’ and ‘Composite’ [Stylosanthes guianensis ‘CIAT 184’, ‘Composite’] and vigna [Vigna unguiculata ‘CIAT 1088‐4’]) were grown during 2009–2010 in Lao PDR, and subjected to three harvesting interval treatments (21, 30 and 45 days). The yield and chemical composition of these legumes were determined. Stylo ‘Composite’ produced the highest average dry matter (DM) yield, followed by stylo ‘CIAT 184’, aeschynomene, canavalia and vigna. Harvesting every 45 days produced higher DM yields than the other treatments. Differences in crude protein (CP) content between species and treatments were small with stylo ‘CIAT 184’ and stylo ‘Composite’ having the lowest values. CP content was highest with the shortest harvesting interval, while the opposite was true for the fiber content (crude fiber, acid detergent fiber and neutral detergent fiber). All legumes produced a higher DM yield with a higher CP content in the wet season than in the dry season. The array of essential amino acids in relation to requirements for growing swine was excellent for all forage legumes except for canavalia. In conclusion, stylo (‘Composite’ and ‘CIAT 184’) and aeschynomene can be recommended for use by swine land‐holder farmers in Lao PDR.