Evaluation of fermentative characteristics and chemical-bromatological composition of sorghum (Sorghum bicolor L. Moench) wet grain silage

Abstract

This study aimed to evaluate the fermentative characteristics and the chemical-bromatological composition of silages of sorghum moist grain. A random sampling design was applied to the experiments in a factorial system with three cutting times after planting (86, 93, and 100 days) (DAP), two types of processing (whole and grinded grains), and four replications. The PVC silos used in the experiments were opened 30 days after ensiling, for sampling and analyzes of the material. Dry matter of the grinded grains silage varied from 58,4% (86 DAP) to 72,6% (100 DAP), and differed from the values of the whole grain silage, whose dry matter varied from 56,9% (86 DAP) to 71,1% (100 DAP). The percentage of CP in the grinded grains silage varied from 9,6% (100 DAP) to 10,1% (86 DAP) with intermediate values for the remaining treatments. The NDF percentage in the grinded grains silage varied from 21,4% (86 DAP) to 35,1% (100 DAP) and was lower than values found for the whole grains silage, which in turn varied from 41,1% (93 DAP) to 46,3% (100 DAP). The percentage of ADF in the grinded grains silage varied from 6,0% (86 DAP) to 6,5% (100 DAP) and averaged 7,9% for the whole grain silage. The values found for the EE were not significant and averaged 2,7%. The high values of pH (4,8 to 6,2) did not characterize for a fermentative process, owing to the high dry matter content of the silages. The results found suggest that sorghum moist grains should be harvested up to 93 days after planting and grinded before ensiling.