THE USE OF ADDITIVES IN THE DEVELOPMENT OF GRASS SILAGE
ABSTRACT
Panicum maximum, a traditional forage grass was subjected to lactic fermentation to produce silage. Ensiling was carried out on P. maximum alone or supplemented with sucrose, common salt or lactic acid bacteria. P. maximum with sucrose, sucrose and salt; sucrose salt and LAB; and sucrose and LAB produced good silage with low pH and good physical/chemical properties. Control fermentation (without any additives or LAB innoculant), P. maximum with salt and LAB; and with only salt or LAB produced silage of poor quality and high pH values. Microbiological analysis showed a rapid elimination of E. coli from all silages and a much slower reduction in the populations of Bacillus and yeasts. A rapid increase was observed in the LAB population, P. maximum with sucrose alone or in combination with other additives showing a higher sustained increase in LAB count than silage treated with other additives and the control silage. There was a complete absence of moulds in the P. maximum treated with sucrose, salt and LAB while moulds grew in P. maximum with sucrose; salt and LAB; sucrose and LAB; and the control fermentation. There was a decrease in the crude protein, carbohydrates, fibre and fat content of all silages while the ash content increased slightly. All treated silage showed a lower deterioration in nutritional content than the control fermentation. The use of sucrose and salt; and sucrose, salt and LAB as additives was shown to provide optimal fermentation conditions for the production of good quality Panicum maximum silage.