Nutritional evaluation of Erianthus spp., Saccharum spontaneum, and Saccharum spp. hybrids as feed

To obtain nutritional information for sugarcane cross-breeding aimed feed utilization, the morphological characteristics, chemical composition, and in situ dry matter degradability (DMD) of each of the ten accessions of Erianthus spp., Saccharum spontaneum and Saccharum spp. hybrids at 6 (6M) and 12 months (12M; after regrowth) were evaluated. For Erianthus spp. and S. spontaneum, the DMD at 48 h after incubation (DMD48h) and the corrected DMD48h (CDMD48h, expressed as DMD48h minus DMD0h) at 6M, exceeded those at 12M. Conversely, for Saccharum spp. hybrids, while the CDMD48h at 6M exceeded that at 12M, the DMD48h at 6M was lower than that at 12M. Compared to all other species, Saccharum spp. hybrids exhibited the highest DMD48h and CDMD48h. It was considered that a harvest with highest DMD could be obtained during the early growing stages in Erianthus spp. and S. spontaneum, but during a later growing stage in Saccharum spp. hybrids. DMD48h of Erianthus spp. correlated negatively with DM, NDFom and ADFom contents at 6 and 12 months after regrowth respectively. The ADL content of S. spontaneum correlated negatively with pooled DMD48h (r = -0.63; P < 0.01) and tended to correlate negatively with pooled CDMD48h (r = -0.47; P < 0.10). The NDFom and ADFom contents of Saccharum spp. hybrids correlated negatively with pooled DMD48h and positively with pooled CDMD48h, whereas these correlations were more affected by advancing maturity rather than the characteristics of accessions. These results suggest that DM and the fiber degradability of the accessions of genus Saccharum and Erianthus spp. could be estimated from certain chemical components, when selecting highly digestible accessions.