Bagaço de cevada na dieta de suínos em fase de crescimento

Abstract

The present work was conducted in the Swine Experimental Unity of the UFRRJ Animal Science Institute, from august to november, 2005, to evaluate different levels of barley bagasse included in diets for swines in growing phase, from 35 to 60 kg of live weight. It was used 20 crossbreed gilts, with 35 kg on average of live weight, in a randomized blocks experimental design with five treatments, and four blocks. The five levels of barley bagasse inclusion were 0, 12.5, 25, 37.5 and 50%, replacing the ration based on the dry matter of the reference ration (0% of inclusion). The performance variables ration intake (RI), barley bagasse intake (BBI), total feed intake (TFI), daily ration intake (DRI), daily barley bagasse intake (DBBI), daily feed intake (DFI), total body weight gain (TWG), daily body weight gain (DWG) and feed conversion (FC), also carcass characteristics and weights of organs and visceras were submitted to variance and polynomial regression analysis. It was observed linear reduction on RI and quadratic effect on all the other performance parameters evaluated. The BBI increased with the BB increasing level while TFI increased until 14.91% then decreasing after this level of inclusion. A quadratic effect was observed on DRI and DBBI while DFI increased until the level of 15.00% then decreasing after this level of inclusion. TWG and DWG increased until levels of 12.89 and 14.00% respectively, then decreasing after this level of inclusion. The FC improved progressively until 13.34% of inclusion then getting worse after this level of inclusion. Were evaluated: hot carcass weight (HCW), cold carcass weight (CCW), carcass length (CL) and carcass yields (CY), backfat thickness (BT), ham weight (HW) and ham yield (HY), palette weight (PW) and palette yield (PY), lomb weight (LW) and lomb yield (LY), and loin eye area (LEA). It was observed a quadratic effect on HCW and a linear reduction effect on PW and PY, as the level of barley bagasse inclusion was increased in the swines diets, with none influence on the other carcass characteristics. The Weights of gastro-intestinal tracts (GIT), viscera (VISC), stomach (SW) and liver (LW) were evaluated. There was not any influence on the weights of these last variables due to the level of BB in the growing phase diet. It was observed linear reduction in the feeding cost (FCT) and quadratic effect in the cost per unit of gain (CPUG), which decreased until 22.72% and increasing after this level of BB inclusion. The best level of BB inclusion in diets for swines in growing phase would be 14.91% for higher total DM intake, 12.89% for higher bodyweight gain and 13.34% for the best feed conversion. BB can be included in the growing diet up to 17,36%, without compromising the carcass quality of swines slaughtered at 100 kg of liveweight. BB can be included up to 22.72% in diets of swines in growing phase for reduction of the feeding costs.