Nutritive value of rice straw supplemented with amirea, corn flour plus urea and soybean meal

Abstract

A trial was carried out to evaluate the dry matter intake and the digestibility coefficients of DM, OM, CP, CF, EE, NFE and the nitrogen balance, with sheep fed amirea (ground corn grain extruded with 15% urea), ground corn grain with 15% urea and soybean meal, associated with 50% or 70% rice straw. The experiment was a factorial arrangement 3 x 2 in a completely randomized design. A digestibility and N balance trial was also carried out feeding rice straw alone. The DM intake per unit of metabolic weight was lower (P < 0.05) with corn + urea or amirea and rice straw 50:50 concentrate: roughage ratio. No effect of nitrogen source or roughage percentage was found (P > 0.05) in the dry matter or organic matter digestibilities, but crude protein digestibility was affected by the roughage percentage (P < 0.05). Interaction between nitrogen source and the level of roughage was found for crude fiber, ether extract and nitrogen free extract apparent digestibilities (P < 0.05). The total digestible nutrients (TDN) values were 74.05% for amirea, 67.27% for corn flour + urea, 62.5% for soybean meal and 33.31 % for rice straw.