Incremental ratio of urea: Urease in alkaline hydrolysis of dried kume grass (Sorghum plumosum var. Timorense) improves its nutritive values

Abstract

This experiment aimed at assessing effects of alkaline hydrolysis using rice husk ash filtrate (RHAF) with or without urea and urease enzyme on nutrient content of dried kume grass. A 6x3 completely randomized design was employed to test 6 treatments, namely RK1 = dried kume grass sprayed with RHAF (15% w/v) and hydrolysed for 3 hours, RK2 = Like RK1 + urea 4%, RK3 = Like RK2 plus urease for urea: urease ratio of 1:2 or 1:3 (RK4) or 1:4 (RK5) or 1:5 (RK6). Measured variables were dry matter (DM), organic matter (OM), crude protein (CP), and crude lipid (CL). General linear model for CRD was employed in data analysis, and Duncan test for treatment difference. Results showed that increased urea: urease ratio significantly effecting CP and CL content, yet no difference between 1:4 and 1:6 ratios. The lowest improvement was in RK1 (7.41% CP and 41.93% CL) and the highest was in RK6 (22.75% CP and 210.16% CL). In the contrary, all treated groups showed a decline in DM and OM. It is concluded that alkaline hydrolysis using RHAF plus urea: urease ratio at 1:4 is the best treatment to improve the nutritive value of dried kume grass.