The trial was conducted to evaluate the effects supplementation with ground corn on grazing dairy heifers diurnal ingestive behavior. Six Jersey heifers, aged of 6 to 9 months and weighing 105.65 ± 18.2 kg, were used. Heifers were grouped into three animals "testers", and kept in an annual ryegrass (Lolium multiflorum Lam.) pasture, under continuous grazing, with variable stocking rate. Two treatments were used, one as control (no supplement) and another supplemented with ground corn being assigned three animals "testers" for each treatment. Daily, at 14 h, the ground corn was fed at 1% LW. Animals were randomly assigned to treatments according to a split splot completely randomized design during four experimental periods. Ingestive behavior was evaluated visually and recorded diurnal times spent grazing, ruminating and idling between 7 am and 6:30 pm. Non supplemented animals showed larger grazing time, but shorter idling time, besides fewer grazing and idling periods than supplemented animals. Supplementation affected the diurnal ingestive behavior of Jersey heifers.
grazing; idling; rumination
