| Popis: |
Our objective was to evaluate the effects of associating feed additives on performance of finishing cattle when fed a high-concentrate diet for 105 days. Twenty-four Angus-Nellore crossbred bulls (iBW, 456 ± 10.04 kg; age, 18 mo) were randomly allocated to three treatments with eight replicates per treatment (animal as experimental unit). The treatments were: 1) Control (MON) - Sodium Monensin, 26 mg/kg DM; 2) Crina® RumistarTM (CR) - a blend of essential oils, 90 mg/kg DM + exogenous α-amylase, 560 mg/kg DM) and 3) CR + HyD® (25-hydroxy-vitamin-D3 at 1 mg/animal/d). The DM intake and animalsˈ weight variables were assessed individually, by using the Intergado® electronic system and the Bosch® Precision Livestock platform placed in the feedlot pen, respectively. Data were analyzed using the Mixed procedure of SAS and means comparison evaluated by Tukey test at P < 0.05. The initial BW was used as a covariate when significant. Feeding CR and CR+HyD increased DMI (13.18 and 12.82 kg vs. 10.77 kg P < 0.01) and tended to increase ADG (1.94, 1.92 vs. 1.68kg/d, P = 0.07) and final BW (654, 652 vs. 628 kg, P = 0.08) compared with MON. Likewise, animals fed CR and CR+HyD had greater carcass ADG (1.38, 1.41 vs. 1.14 kg/d, P < 0.01), and HCW (368.53 and 371.87 vs. 344.13 kg; P < 0.01) compared to MON. In addition, feeding CR+HyD increased the dressing percentage in 2.1 percent points compared with MON (57.4 vs. 55.3%; P < 0.03). The G:F and the biological efficiency were similar among treatments (P = 0.50). We conclude that including Crina® RumistarTM +HyD® can be used as a tool to increase carcass production by feedlot cattle. |
