Effect of Exogenous Fibrolytic Enzymes on Dry Matter and Cell Wall In vitro Digestibility of Guinea Grass Hay

This experiment was conducted to study the effect of an exogenous fibrolytic enzymatic mixture (Fibrozyme 0 1.0, 1.5 g enzyme/kg DM) on in vitro degradation (IVD) of dry mater (DM), neutral (NDF) and acid (ADF) detergent fibers of Guinea grass (Panicum maximum var. Mombasa) hay cut at 35 and 90 d. First phase of Tilley and Terry technique was used with 24, 48 and 72 h incubation. The IVD of DM at 72 h for Guinea grass cut at 35 d was higher than that of Guinea grass cut at 90 d. For all testing times the IVD of ADF of Guinea grass cut at 35 d was higher than that of Guinea grass cut at 90 d. Compared to the control, the enzyme increased IVD of ADF cut at 35 d for all incubation times. However, at 90 d IVD of ADF only increased at 24 h of incubation with enzyme. According to these results, the exogenous fibrolytic enzymatic mixture increases the in vitro digestibility of the cell wall of Guinea grass hay.