The objective of this work was to evaluate the effect of the addition of crescent levels of urea, with or without urease, on sugarcane bagasse nutritive value. The experimental design was a completely randomized design in a factorial arrangement (4 x 2) + 1 (control), with four replicates. The evaluated factors were urea levels (2.0, 4.0, 6.0 and 8.0% DM), urease levels (presence - 20% of urea fresh matter - and absence) and a control treatment (0.0% urea and without urease). There was an effect of urea addition (63.3%) on the control (69.6%) and effect of urease presence (64.4%) on its absence (62.1%) for the dry matter (DM) content. The smallest estimated DM content (62.5%) was observed at 6.2% urea level. The crude protein (CP) content linearly increased with the addition of crescent levels of urea (12.0%) as compared to the control (1.2%), without urease effect. The neutral detergent fiber (NDF) content of ammoniated materials (81.4%) was smaller than the control (84.7%), with a negative linear effect of the crescent levels of urea. There was higher NDF content in the treatments with the presence of urease (82.1%) than on the treatments without urease (80.8%). The average in vitro dry matter disappearance (IVDMD) of the control treatment (23.2%) was lower than average urea addition treatments (28.5%), with positive linear effect by the crescent addition of the urea levels. There was no urease effect on IVDMD. The ammoniation with urea improved the sugar cane bagasse nutritive value, without necessity to add urease.
ammoniation; bagasse; sugarcane; urea; nutritive value
