Influência da utilização de aditivos químicos no perfil da fermentação, no valor nutritivo e nas perdas de silagens de cana-de-açúcar

The objective of this trial was to evaluate the effects of chemical additives in the dry matter losses, fermentation profile, and nutritive value of sugar cane silages. The trial was carried out in a completely randomized experimental design with four replicates per treatment. The following additives were applied to the fresh forage during the ensiling: control (without additive), L. buchneri, calcium oxide and calcium carbonate,1.0 and 1.5% (wet basis) each, and calcium sulfate 1.0% (wet basis), all of them diluted in to 40 L of water per ton of fresh forage. The variables analyzed were: total and gaseous dry matter losses, dry matter recovery, fermentation end products, and nutritive value. The use of calcium oxide or calcium carbonate were effective in reducing dry matter losses and gaseous production and had the highest dry matter recovery rate. Both silages had also low ethanol content and, as a result, had greater concentrations of residual water soluble carbohydrates and lactic acid. The addition of calcium oxide and calcium carbonate at the time of ensiling produced silages with higher nutritive value compared with all other treatments, due to the increase of ash content and dry matter and organic digestibility and also, by reducing the fiber content. The crude protein content range was similar to the values observed in the fresh forage. The treatments with L. buchneri and calcium sulfate were ineffective in altering the fermentation process of sugar cane silages and became similar to the control silages. In summary, the overall analysis pointed out that the treatment containing calcium oxide and calcium carbonate improved the fermentation and storage process.