MÉTODO DE OBTENÇÃO DE MATÉRIA SECA E COMPOSIÇÃO QUÍMICA DE VOLUMOSOS

It was aimed determinate the influence of drying methods on nutritional composition of different roughages. The experimental material were four grass species ( Urochloa brizantha  cv. Marandu,  Urochloa brizantha  cv. MG4,  Cynodon dactylon  cv. Coastcross e  Panicum maximum  cv. Aries), one forage legume ( Stylosanthes  cv. Campo Grande) and two silages ( Zea mays  e  Triticum aestivum  cv. BRS Umbu). The drying methods were based on use of forced air oven or microwave oven. The experimental design were a 2 x 8 factorial arrangement (2 drying methods and 8 roughages) with 4 repetitions. There was not effect of drying method on roughages dry matter content. Microwave oven drying increased neutral detergent fiber. There was an interaction between drying method and roughage. Increased contents of crude protein (estilosante), neutral detergent insoluble nitrogen (Coastcross, MG4, Marandu e estilosante) and ether extract (MG4, estilosante e Aries) were observed when roughages were dried using microwave oven. The microwave oven usage is an alternative to obtain the dry matter content of roughages; however this technic may affect the sample composition. Keywords:  forced air oven; microwave oven; cell wall; crude protein; ether extract.