Comportamento ingestivo de novilhas recebendo suplementação proteica com ou sem monensina

Abstract

The objective of this reserach was to evaluate the ingestive behavior of heifers in grazing, receiving mineral or protein supplementation with or without monensin addition. The treatments consisted of mineral supplementation; mineral supplementation with monensin; protein supplementation and protein supplementation with monensin. Mineral and protein supplement were provided ad libitum and 0.5 kg animal-1 day-1, respectively. Monensjn amount used for mineral supplement was 2.0 g kg-1 of product and for the protein 400 mg kg-1 of product. Were used 40 heifers with predominance of zebu (Nelore) blood, with an initial average of 9 months. Grazing and rumination times had interaction between supplementation and addition of monensin (P <0.05). Protein supplementation with addition of monensin reduced grazing time and increased rumination time. Addittion of monensine in the mineral supplement increased grazing time, however, did not alter rumination time. Animals had preference for grazing in the late afternoon, however, it was not very clear the effect of the monensin in the period that the animals performed the behavioral activities. Thus, an inclusion