Comportamento ingestivo diurno de novilhos em pastejo submetidos a níveis crescentes de suplementação energética

The trial aimed to observe the ingestive behavior of grazing beef steers submitted to different energetic supplementation levels and kept under an improved natural pasture. Thirty eight beef steers without definite breed, aging 12 to 15 months and weighing 159,97 kg were used. Animals were kept under set stocking in a natural pasture improved with Lotus Subbiflorus and invaded with Eragrostis plana Ness. Two levels of ground sorghum grain were offered as an energetic supplement, and treatments consisted of control or without supplement (T0); 0,75% of mean live weight (T0.75), 1,5% of mean live weight (T0.75). Animals were randomly assigned to treatments according to a complete randomized design. Considering the overall mean, diurnal grazing time (P=0.0059), total rumination time (P=0.0013) and walking time (P=0.0076) followed by a quadratic trend in relation to the supplement levels, and showed larger values for control, T0.75 and T1.5, respectively. Diurnal idling followed a positive linear trend with increasing supplementation levels (P=0.0001). Biting rate and total bites number followed linear (P=0.0001) and quadratic trends (P=0.0002), respectively, with increasing supplementation levels. There were no differences for feeding stations visited per minute and for time spent at the trough between treatments.