ADF contents and as a result of this, ED of these treatments has increased.
In vitro gas production (ml) and estimated parameters of ensiled brewers’ grain are presented in Table 4. With adding of additive material (molasses and sulfuric acid) to the silage, rate of gas production (c) and cumulative gas production at 24, 48 and 96 h after incubation significantly increased than control group (p < 0.05). The highest cumulative gas production (after 24, 48 and 96h incubation) was observed for 2% sulfuric acid (p < 0.05). It seems that, different chemical composition (such as NDF and ADF) of ensiled BG affected the rate and extent of gas production. Kazemi et al. (2012) reported that there was a negative correlation between NDF and ADF with gas production parameters. Also Kamalak et al. (2005) reported this negative correlation. The increase in gas production parameters for 1 and 2% sulfuric acid are possibly associated with decreased NDF and ADF contents. It is well known that gas production is basically the result of fermentation of carbohydrates to acetate,