The objectivesof this experiment were to evaluate the performance of young bulls fed totalrations prepared with additive treated or untreated sugarcane silages and evaluatethe additive effects on silages fermentation. Thirty young Canchim bulls averaging312 kg were allotted to a completely randomized experimental design to evaluatethree types of isoproteic and isoenergetic rations (roughage:concentrate ratioof 35:65): ration with silage without additive (control), ration with silagetreated with urea (5 g/kg of fresh forage - FF) + sodium benzoate (0.5 g/kgFF), ration with silage inoculated with Lactobacillus buchneri (5 ×104 cfu/g FF). Silages had pH adequated to conservation (<4.2),low levels of butyric acid (<3 g/kg in DM) and high levels of acetic acid(>53 g/kg in DM). The silage treated with urea + benzoate and the inoculatedsilage presented lower ethanol concentration when compared to the untreatedsilage (43, 73 and 92 g/kg in DM, respectively). The silage treated with urea+ benzoate had higher crude protein content and total digestible nutrients whencompared with other silages. The type of ration affect neither body weight gain(BWG) nor DM intake, but feed conversion was better for animals that receivedcontrol ration in relation to those fed ration with inoculated silage (5.71vs 6.45 kg DM/kg BWG).
