FORAGE MIXTURES FOR DAIRY COWS - THE EFFECT ON DRY-MATTER INTAKE AND MILK PRODUCTION OF INCORPORATING EITHER FERMENTED OR UREA-TREATED WHEAT, BREWERS GRAINS, FODDER BEET OR MAIZE SILAGE INTO ON GRASS SILAGE

摘要

One hundred and two multiparous Holstein/Fresian dairy cows were used to examine the effect on food intake and milk production of replacing 330 g/kg dry matter (DM) of first-cut perennial ryegrass silage (GS) with either fermented (FW) or urea (40 g/kg DM) treated (UW) whole-crop wheat, brewers' grains (BG), folder beet (FB) or maize silage (MS). A forage mixture containing GS and 750 g/kg DM of maize silage (MSH) was also offered. Dietary crude protein (CP) concentrations were equalized by offering all cows 6 kg DM per day of an appropriate concentrate supplement. DM intake and milk yield of cows offered GS (15.3, 23.0 kg/day) were increased (P<0.01) by the inclusion of BG (16.3, 26.7 kg.day), FB (17.6, 25.9 kg/day), MS (16.6, 26.4 kg/day) and MSH (18.5, 27.6 kg/day). BG, FB and MS all produced similar increased in milk yield. Although the inclusion of FW and UW increased (P<0.05) DM intake, milk yield was not significantly affected. The differences between the highest and lowest milk fat concentration, produced by FB (42.9 g/kg) and GS (29.9 g/kg) were increased (P<0.01) by BG (1.07, 0.82 kg/day). FB (1.11, 0.83 kg/day) or UW (1.00, 0.73 kg/day). Results show that farmers should consider replacing a major part of the grass silage component with an alternative forage or forage substitute.