Porte da gramínea e inclusão da cunhã modificam o valor nutritivo da silagem de capim-elefante

The objective of this work was to evaluate the nutritional value of silages from tall-sized and dwarf elephant grass ( Pennisetum purpureum ) genotypes, intercropped or not with butterfly pea ( Clitoria ternatea ). The experiment was performed in randomized complete blocks, in a 4x2 factorial arrangement (four genotypes × two cropping systems). The genotypes intercropped or not with butterfly pea were: IRI-381 and Elephant B, tall sized; and Taiwan A-146 2.37 and Mott, dwarf. Forage was harvested 60 days after regrowth. In the silage from Mott grass intercropped with butterfly pea, lower contents of lignin (78.1 g kg -1 ), neutral detergent fiber (636.0 g kg -1 ), and neutral detergent insoluble protein (13.15 g kg -1 ), besides a greater dry matter recovery (873.3 g kg -1 ), were observed. The silage from Taiwan A-146 2.37 intercropped with the legume showed a greater crude protein content (136.1 g kg -1 ). In both silages, the ammonia nitrogen contents were quite reduced (26.4 g kg -1 ). However, greater residual water-soluble carbohydrate contents were observed in the silages from the intercrop (1.85 mg g -1 ) and from the Mott grass monocrop (1.51 mg g -1 ). Moreover, there was a lower in vitro dry matter digestibility (676.7 g kg -1 ) for the silage from the intercrop. Dwarf genotypes increase the nutritional value of elephant grass silage, compared with the tall-sized ones. Intercropping with butterfly pea improves silage fermentation characteristics, despite reducing its digestibility. Therefore, the ensilage of dwarf Mott elephant grass intercropped with butterfly pea shows more promising results.