ABSTRACT Sugarcane (Saccharum officinarum L.) ensilage presents serious limitations due to the conversion of soluble carbohydrates into ethanol, thus, it is necessary to use additives that reduce losses of DM during the ensilage process. The aim of this study was to evaluate the effect of increasing levels of detoxified castor-bean (Ricinus communis L.) meal (DCBM) on the nutritive value, fermentation pattern, stability and losses of sugarcane silages. Twenty mini-silos with sugarcane and five different concentrations of DCBM (0, 50, 100, 150 and 200 g kg-1 fresh matter) were prepared in a completely randomized design with five replicates per treatment. After 60 d, silage was sampled to determine chemical-bromatological composition, fractionation of carbohydrates and protein content, ammoniacal N (N-NH3) and losses through gases and effluents. The addition of DCBM increased (P < 0.05) DM content, crude protein, fraction A + B1 of the total carbohydrates. However, it reduced (P < 0.05) the levels of neutral and acid detergent insoluble fiber, fraction B1 + B2 of total N and N-NH3. The addition of DCBM reduced the losses of total DM but decreased silages aerobic stability. The addition of 150 g kg-1 DBCM improved the nutritional value, fermentation pattern and reduced losses of sugarcane silages