Desirability index: a multivariate analysis of the fermentation standard of manitoba silages

Abstract

The objective of this study was to evaluate manitoba silage in relation to wilting and storage of same, by calculating the index of desirability, obtained after multivariate analysis "Experiments with Mixtures". It was used a completely randomized 2 x 3 factorial arrangement, considering as fixed factors wilting (0 and 6 hours) and storage (15, 45 and 90 days), totaling six treatments quadrupled. The variables analyzed were: dry matter, crude protein, neutral detergent fiber, acid detergent fiber, lignin, ash, soluble carbohydrates, pH, buffering capacity and epiphytic microflora for filamentous fungi and total bacteria, with emphasis on the presence of Bacillus. In all variables, or wilting and storage time showed significant difference (p<0.05). The wilted branches silages showed higher nutritional quality for ruminants consuming presenting optimal values of storage (87.77 and 82.33 days), respectively, with I = 1.0. This multivariate technique proved to be an excellent tool to determine a best wilting and storage in this material ensiled.