Valor nutricional de pré-secados de azevém potro sob diferentes estratégias de adubação e etapas de produção

Abstract

Forage conservation has the principle of storing the raw material in order to ensure its quality. The objective of this study was to evaluate the nutritional profile of foal ryegrass, preserved as pre-dried, submitted to different fertilization strategies applied at base and cover. The fermentation profile was studied by determination of dry matter content, pH and ammoniacal nitrogen (N-NH3). In the evaluation of the nutritional profile, we studied the bromatological composition, the carbohydrate fractions (A + B1, B2 and C) and the consumption of dry matter in relation to live weight (CDMLW). In the fresh material, the combined base and cover fertilization showed a reduction in crude protein (CP). The carbohydrates levels were higher in the absence of base fertilization and with application of 20 Kg/N/ha. Both basal and cover fertilization promoted higher levels of non-fibrous carbohydrates (NFC), total digestible nutrients (NDT) and A + B1 fraction of carbohydrates in the fresh material, as higher fertilizer doses were applied. The doses of 20 kg/N/ha and 40 Kg/N/ha in coverage, promoted the best pH values at the end of the fermentation period. The absence of cover fertilizer and the application of 20 Kg/N/ha, reflected in the best amounts of neutral detergent fiber (NDF) for pre-dried, 568.84 g/Kg and 557.09 g/Kg, respectively. The CDMLW presented better values in the dose of 10 Kg/N/ha. According to the results obtained, the ryegrass Potro can be stored as pre-dried, presenting satisfactory nutritional quality in different strategies of basic fertilization and coverage.