Effect of Forage Peanut Inclusion in a Marandu Grass Pasture on Forage Disappearance Compared to Marandu Grass Fertilized.

Nowadays farm producers are looking for alternatives to synthetic nitrogen fertilizer. One of the options is the inclusion of legumes into grasslands. Legumes can contribute with nitrogen and the high nutritive value to the animal production system based on grassland. This research aimed to evaluate the forage disappearance of marandu grass grassland intercropped with forage peanut, fertilized with nitrogen (N) and, the control without N source. That composed the treatments with 4 replicates managed under intermittent grazing by dairy heifers. The criterion of grazing start was 95 % LI and a one day of period of occupation. When ANOVA was significant to analyze the effect of treatment, Tukey test was performed and, for the effect of grazing cycles, a polynomial orthogonal contrast was tested. Forage disappearance was affected by treatments (P=0.03), but there was neither an effect of grazing cycles (P=0.25) nor the interaction among treatments and cycles (P=0.27) on this variable. The forage disappearance averages were 4019 (±1544), 1394 (±419) and 1944 (±861) kg DM ha^-1 d^-1 for the treatments fertilized, intercropped and control, respectively. The inclusion of forage peanut negatively affected the forage disappearance. A system animal performance assessment should be carried on in order to better understand the effect of the inclusion of this legume to a grassland.

Keywords: forage intake, mixed pastures, nitrogen input.