Nutritive value of rice straw as affected by ensiling with urea and urease sources at various moisture levels

Abstract

An experiment was conducted to study the effect of urease sources on proximate composition, NH3-N production, energy value, in situ disappearance of dry matter (DM), crude protein (CP) and digestibility of organic matter of urea ensiled rice straw. Rice straw (RS) was ensiled with the combination of urea, soybean seed meal (SSM), cowpea seed meal (CSM) or midden soil (MS) at different moisture levels. Ensiling with urease sources resulted in improvement of CP, organic matter (OM), ether extract (EE), and decrease in crude fiber (CF) and ash. All the treatments had significantly higher CP than untreated straw. Similarly, OM and EE content for urease treated straws were higher over untreated. In sacco disappearance of DM and CP were also higher in treated group than untreated straw. But all the treatments were lower in CF and ash contents than control. The interaction between additive sources and moisture levels were significant for OM, CP, CF and NFE (nitrogen free extract) content but nonsignificant for ash. It may he concluded that nutritive value of rice straw can be improved by adding 5% urea and 5% urease containing plant sources like SSM, CSM and preserved for at least 4 days under anaerobic condition at 40% moisture level.