Ruminal degradation of corn silage and rice straw using exogenous fibrolityc enzymes - DOI: 10.4025/actascianimsci.v30i4.6462

Abstract

This study evaluated the effect of fibrolytic enzyme addition (cellulase and xylanase) on the dry matter (DM), crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF) and hemicellulose in situ degradability of corn silage (CS) and rice straw (RS), using six cattle cannulated on the rumen. Acid detergent insoluble nitrogen (ADIN/total N) was evaluated. The fibrolytic enzymes were extracted from Aspergillus niger and Trichoderma longibrachiatum fungi, supplied at 0.75 g/kg of DM/animal/day, through ruminal cannula. The incubation times were 0, 3, 6, 12, 24, 48, 72 and 96 hours. The incubation residues were compared by scanning electron micrograph (SEM). Soluble fraction of DM and CP corn silage increased with enzyme supplementation. There was no effect of enzymes on the cell wall degradation of roughages. The enzyme addition did not alter the ADIN/total N level of corn silage; however, this ratio was increased on the rice straw incubated during 12 and 48 h. In general, the SEM observations showed increased bacterial colonization on the cell wall of roughages with fibrolytic enzymes addition, although without effect on ruminal degradation.