The goal of this work was to determine the accuracy of the Grazemore model to predict milk yield and dry matter intake (DMI) of grazing cows fed pasture and forage supplements. Data were obtained from studies where pasture was complemented with silages, comprising 30-40% of DMI. Twelve dietary mixtures were used in this evaluation. Liveweight, days in milk, pre-grazing mass, allowance and diet composition were collected during the trials and used as inputs. There was a good correlation between actual and predicted milk yield (r²=0.72) and DMI (r²=0.90) by the model when actual production was regressed against predicted responses.