METHODS TO IMPROVE UTILIZATION OF RICE STRAW I. EFFECTS OF MOISTENING, SODIUM CHLORIDE AND CHOPPING ON INTAKE AND DIGESTIBILITY

Two studies were conducted using 40 cross-bred bulls to study the effect of chopping, moistening with water or common salt solution on the nutritive value of rice straw (variety BG-400). Moistening with water did not significantly effect digestibility or intake of rice straw. As compared to straw fed in the long form, chopping did not significantly influence intake (2.33 vs 1.97kg $100kgBW^{-1}day^{-1}$, respectively), but significantly (p<0.05) decreased the digestibility (41.6 vs 37.4%) and intake of digestible dry matter (0.99 vs 0.74kg $100kgBW^{-1}day^{-1}$). Rice straw moistened with 2 or 4% common sea salt solution and directly fed to animals (Exp. 1) did not significantly effect its digestibility (43.9 and 43.1%, respectively) or intake (2.66 or 2.59kg $100kgBW^{-1}day^{-1}$, respectively), but over night storing of 2% salt solution sprayed straw (Exp. 2) significantly reduced its digestibility (33.6%). The latter is difficult to explain because the sodium concentration (mg/g straw dry matter) was lower than 4% salt solution treatment used in experiment 1 (3.30 vs 5.22). It is concluded that chopping, moistening with water or NaCl salt solution did not significantly improve the nutritive value of rice straw.