Effect of the maturity stage of grass at harvesting on the chemical composition of grass clover silage

The objective of this research was to determine changes in chemical composition and fermentation quality among grass clover silages harvested at different maturity stages. Grass clover silage was harvested in three maturity stages of orchardgrass (Dactylis glomerata L.) that was a dominant grass in the sward: late vegetative (GSI), internode elongation (GS2) i and flowering (GS3). Classical chemical analysis methods were used to analyse 16 samples of each of the maturity stage. Dry matter (DM) content of GSI, GS2 and GS3 was 396, 408 and 463 g kg(-1) of the fresh sample, respectively, while crude protein (CP) content was 120, 98 and 90 g kg(-1) DM respectively. While comparing GS3 and GSI, delaying the term of grass harvesting significantly increased DM content (P<0.001), organic matter, (P<0.001), neutral detergent fibre (NDF) (P<0.05) and acid detergent fibre (ADF) (P<0.001). Early cut silage had significantly higher content of CP (P<0.001) in comparison with medium and late cut grass silage. It was concluded that maturity stage of grass clover at harvesting has significant influence on silage chemical composition. If the aim of production is higher quality grass silage, grass has to be cut at the earlier maturity stage.