Composition and in vitro digestibility of leaves and stems of grasses and legumes harvested from permanent mountain meadows at different stages of maturity

Abstract

Chemical composition and in vitro digestibility were determined in stems and leaves hand-separated from grasses and legumes obtained from the first and subsequent cuts of a permanent meadow. Grasses from the first cut were classified in four groups according to their stage of maturity: vegetative, boot, head-bloom and seed stage. Crude protein (CP) content was higher and neutral detergent fibre (NDF) content lower in legumes than in grasses, and in leaves than in stems. CP decreased and NDF increased with maturity in grasses. In general, legumes were more digestible than grasses. The digestibility of grasses harvested in the first cut decreased with increasing maturity. Leaves were more digestible than stems in legumes and grasses, although the relative difference between botanical parts was much larger in grasses than in legumes. The differences in digestibility between leaves and stems became more pronounced with increasing maturity, especially in terms of cell wall digestibility. As for forage quality, early cutting of permanent meadows would be recommended, so that grasses are harvested before they reach an advanced stage of maturity.