Mixed silage of BRS capiaçu grass with spineless cactus: impacts on fermentative characteristics, chemical composition, and digestibility

Abstract

We determined the most suitable level of inclusion of spineless cactus in silage of BRS capiaçu on the fermentative profile and nutritional value of the silage produced. The treatments consisted of the inclusion of spineless cactus (Opuntia spp.) in BRS capiaçu grass ensilaged with increasing proportions (15%, 30%, 45%, and 60% of natural matter-NM) and a control treatment. A completely randomized design with five treatments and eight replications was used. The BRS capiaçu grass was harvested after 100 days of regrowth. For the silage, experimental PVC silos of known weights, 50 cm long and 10 cm in diameter, were used. The inclusion of spineless cactus in BRS capiaçu grass ensilage resulted in a linear increase in pH (P < 0.01), ammonia nitrogen content (P < 0.01), and effluent losses (P < 0.01). Quadratic effects were observed for lactic acid (P < 0.01) and acetic acid (P < 0.01), with respective maximum points for 22% and 24%. The highest values of the digestibility of dry matter (DM), organic matter, and neutral detergent fibre were found for inclusion levels of 47.11%, 42.35%, and 35.44%, respectively. The most suitable inclusion level was between 15 and 30% of NM.

Keywords

• Digestibility
• ammoniacal nitrogen
• pH
• crude protein
• dry matter content