Intakes of DM (kg day−1 : B1 = 21.0, B2 = 20.6 and B3 = 20.0) and neutral detergent fibre (NDF; kg day−1 : B1 = 7.0, B2 = 6.4 and B3 = 6.3) decreased, whereas starch intake increased (kg day−1 : B1 = 3.1, B2 = 3.5 and B3 = 4.0) with increasing maturity at harvest. The apparent organic matter (OM) digestibility (g kg−1 : B1 = 800, B2 = 774 and B3 = 729) decreased with increasing maturity stage, and consequently so did the digestible OM intake.