Total gas production, methane gas and in vitro dry matter digestibility of diet containing corn straw and cassava peel supplemented with urea and sulfur

Abstract Supplementation of urea and sulfur in fiber feed and cassava peel as energy source in diet is needed to optimize the fermentation process in the rumen, so that dry matter digestibility increases., methane decreased. Methane gas determines feed energy efficiency. The purpose of this study was to evaluate supplementation of urea and sulfur in modulating rumen fermentation on dry matter digestibility and gas production especially methane. This research was designed using a randomized block design with 7 treatments and 4 groups. The treatments were supplementation of urea and sulfur (S) in a diet based on sweet corn straw and cassava peel with a crude protein content of 10% and TDN 66.%. Treatments: T1= basal diet (30% corn straw and 30% cassava peel); T2= T1+ 0.5% urea; T3= T1+1% urea; T4= T1+0.1% S; T5= T1+0.2% S; T6= T1+0.5% urea+0.1% S; T7 =T1+1% urea +0.2% S. The result showed that supplementation of urea and sulfur increased invitro dry matter digestibility (P<0.01). However, total gas production and methane gas produced, were not significantly different (P>0.05) by urea and sulfur supplementation. In conclusion, supplementation of 1% urea and 0.2% sulfur in a diet containing 30% corn straw and 30% cassava peel increased dry matter digestibility but did not decrease methane gas. The dry matter digestibility value was 69.39%, while the total gas and methane gas were 92.60 mL/g DM and 60.96 mL/g DM, respectively.