314 Carbohydrases Enzymes Improve the Productive Performance of Grazing Nellore Bulls Fed Different Nutritional Plans During the Rainy Season

Abstract The aim with this trial was to evaluate two nutritional plans with the addition of dosages of carbohydrases enzyme blend on productive performance of grazing Nellore bulls in rainy season. One hundred and two contemporary Nellore steers (BW = 294.10 ± 3.35 kg) were equally distributed in six paddocks (17 steers/paddock) following a completely randomized design in a 2x3 factorial arrangement, being the factors two nutritional plans: mineral-proteic supplementation (Fosbovi® Proteico 30; PS) offered at 0,1% BW or mineral-protein-energetic supplementation (Fosbovi® Proteico-Energético 25; PES) offered at 0.3% BW); and three levels of enzymatic carbohydrases blend (0, 4,75 or 9,50 g/animal/day). The enzymatic blend was mainly composed by beta-glucanase and xylanase enzymes (Ronozyme® VP and Ronozyme® WX); Both enzymes and supplemented were provided by DSM Nutritional Products Brasil S.A. Supplement intake and animal weighting were carried out daily and individually by an automatic scale system installed in each paddock. Data were analyzed using PROC MIXED of SAS and means were compared by polynomial regression. Animals that received PES had greater ADG (0.896 vs. 0.775 kg/day; P < 0.001) compared to those fed PS. Intermediary level (4.75 g/day) of carbohydrate enzymes also presented the highest ADG in PES compared to 0.0 level (0.941 vs. 0.896 kg/day; P = 0.006). Still, higher enzyme levels (9.5 g/day) presented greater ADG on PS, when compared to 0.0 level (0.852 vs. 0.775 kg/day, P = 0.006). PES animals presented greater intake, compared to PS (1.112 vs. 0.432 kg/day, P < 0.001). According to polynomial regression, it is recommended to include 4.75 g/day of these carbohydrases enzymes in PS and 4.39 g/day in PES for growing Nellore bulls in rainy season.