The objective of this study was to determine the nutritive value of fermented forage from semi-natural grassland harvested at 3 cutting heights: (i) cutting height 2 cm, (ii) cutting height 6 cm and (iii) cutting height 13 cm.
Fresh forage was wilted separately according to investigated treatments for 24 hours before ensiling into experimental silos. After 35-day fermentation, the ensiled forage dry matter (DM) was determined while the chemical composition, fermentation quality and biological quality parameters were predicted by NIR spectroscopy. The following parameters were predicted: corrected DM (CDM), crude protein (CP), organic matter (OM), neutral detergent fiber (NDF), acidic detergent fiber (ADF), metabolic energy (ME), fermentable ME in ME (FME/ME), NH3-N, sugar residues, the digestibility of the OM in the DM (D-value) and CP degradability.
Ensiled forage cut at 13 cm above the ground level had significantly lower OM content (P < 0.05) but higher ME, and D-value (P < 0.05) in comparison with forage cut at 2 or 6 cm above the ground level.
The CP content was significantly affected by the cutting height (P < 0.001). The CP content was the highest at forage cut at the highest residual stubble height and was getting lower as the cutting height decreased (P < 0.001).
Cutting at 2 cm above the ground level resulted in forage lower in sugar residues (P < 0.05) in comparison with cutting at higher residual stubble height (6 cm and 13 cm).
It was concluded that the higher cutting height promotes higher nutritive value of fermented forage from semi-natural grassland compared to the quality of fermented forage defoliated at the lower cutting height.