Studies on the effects of different chemical additives on the nutritive value of ensiled barley distillers’ grain (BDG) using in vitro techniques

Abstract

An experiment was carried out to evaluate four different acids as additives (Lactic: C₃H₆O₃, Acetic: CH₃COOH, Hydrochloric: HCl and Sulfuric:H₂SO₄ acid) and a control group (without any additive) for their effects on chemical composition, in vitro gas production and in situ dry matter disappearance of ensiled barley distillers grain (BDG). Dry matter (DM) content of ensiled BDG ranged from 22.12 to 23.85 %, Crude protein (CP), Ash content, Neutral detergent fiber (NDF) and Acid detergent fiber (ADF) ranged from 22.70 to 23.55 % DM, 3.62 to 5.47% DM, 47.30 to 58.40 % DM and 37.45 to 39.45% DM respectively. BDG treatment with sulfuric acid, significantly influenced the NDF and ADF contents than other treatments (p<0.05), so this parameters decreased than those of control group. Treatment of BDG with 0.5% sulfuric acid had the lowest NH3-N and pH than the corresponding control group (P<0.05). There was a higher content of effective degradability (ED) and dry matter disappearance (24hours) for this treatment (0.5% Sulfuric acid). All gas production parameters such as cumulative gas production (after 24, 48 and 96 h) and constant rate of gas production (C_gas) were highest for ensiled BDG with 0.5% sulfuric acid compared to those of control group (p<0.05). It appears that a low level of chemical additives (especially sulfuric acid) may be effective to improve nutritive value of ensiled BDG.