The effect of different levels of daily allowance and supplementation on intake, milk production and composition and per hectare productivity was studied. Pasture consisted of an association of alfalfa (Medicago sativa), tall fescue (Festuca arundinacea) and prairie grass (Bromus wildenowii) and high moisture corn was used as supplement. 32 cows were allocated to four levels of pasture allowance (NA) and two levels of energy supplementation (SE). Pasture intake and individual and per hectare production were affected by NA, but SE had no signifi cant effect. No interactions were detected between any of the variables. Milk composition were not affected by NA, whereas only non fat solids were affected by SE. Liveweight change and condition score did not show differences among treatments. Urea level in both, plasma and milk, was not affected by NA, whereas the level of urea in plasma showed a trend to be different and the level of urea in milk was signifi cantly different for SE. Critical levels of pasture allowance which directly affect the productivity per hectare, need to be reached in order to perform a signifi cant increase of individual production. Milk fat and protein concentration did not appear to be responsive variables to different levels of supplementation and allowance, whereas the little variation in urea levels, as a response to a greater level of supplementation, did not make this a valuable tool to improve the milk protein constituents.