The effect of grazing residual control methods on cow intake and milk production in late spring

Mowing of pasture before grazing, topping of pasture after grazing, and regrazing of pasture were studied as methods to control post-grazing residuals at optimum levels for pasture quality and growth. The study was conducted over a 14-day period during November 2009 and the impact of each of these methods of residual control on cow intake and milk production was measured. Cows were split into eight herds of 15 cows and allocated to one of four treatments with two replicates. Compared to the control, topping pasture pre-grazing reduced (P < 0.01) cow intake by 2.3 kg DM/cow/day, milk yield by 2.9 L/cow/day (P < 0.05) and milk protein percent (P < 0.05). The pasture that was mown before grazing was significantly (P < 0.05) higher in neutral detergent fibre and significantly (P < 0.05) lower in metabolisable energy, than all other treatments. This study has indicated that pre-graze topping as a method of maintaining low pasture residuals during spring reduces milk production and cow intake.