Parte aérea da mandioca (Manihot esculenta Crantz) na ensilagem com gliricídia (Gliricidia sepium)

Abstract

Two experiments were conducted to evaluate the chemical composition, fermentation characteristics, aerobic stability, ammonia nitrogen and pH of Gliciridia silages with inclusion levels of aerial part of ensiled cassava. The experiments utilized two hundred and eighty experimental PVC silos (40x10cm) subdivided in two phases: both, first and second phase of the experiment utilized 140 micro PVC tubes silos. The experiments were conducted in the sheep unit and the analysis were performed in the nutrition laboratory at the Federal University of Bahia Reconcavo, located in the municipality of Cruz das Almas, Bahia, Brazil. The silos were stored at room temperature and their openings occurred on days one, three, five, seven, fourteen, twenty eight fifty-six of ensiling. In the first phase of the experiment the ensiled material was wilted. In the second phase the silage was made with in natura material. The material was treated with Gliricidia (GLI) using the following substitution levels for aerial parts of cassava (PAM): 0% (100% GLI), 20% (80% GLI), 40% (60% GLI), 60% (GLI 40%), 80% (20% GLI) for both wilted and in natura material. The experimental design was a completely randomized design (four replications, five levels of aerial part of cassava and seven days of opening). A total of 140 experimental PVC silos (40x10cm) were used for each condition the material was subjected to. The parameters determined were: Dry matter (DM), crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), lignin (L), hemicellulose (HM), ammonia nitrogen (NH3), organic matter (OM), neutral detergent fiber ash and protein (NDFap) correction, neutral detergent insoluble protein in the dry matter (PIDNms), neutral detergent insoluble protein protein correction (PIDNpb), neutral detergent insoluble protein (FDN PIDNfdn), insoluble ash neutral detergent (CIDN), neutral detergent insoluble ash (FDN CIDNfdn), neutral detergent insoluble ash in dry matter (CIDNms), fibrous carbohydrates and proteins not ash correction (CNFCP), dry matter losses (losses) and pH. Interpretation of the data was done by analysis of variance and regression models. For statistical analysis, the data was subjected to analysis of variance using the General Linear Model procedure in SAS (Statistical Analysis System). To study the effect of all treatment levels within days of opening, Student "t" test at the 5% significance level was used. Also, the effect of opening days in each inclusion level of aerial parts of cassava was observed through regression analysis. The choice of the best model was based on the significance of the parameters tested using the Student "t" test and the values of coefficients of determination (R2). Gliricidia in consortium with the aerial part of cassava silage showed suitable chemical characteristics for making silage, indicating to be a great alternative to conservation in the form of silage.