The fermentative characteristics and the chemical composition of elephant grass silages with increasing levels of dehydrated passionfruit by-product (DPB) were evaluated. Five DPB addition levels (0.0; 3.5; 7.0; 10.5; and 14.0%; in a grass fresh matter basis), in a complete randomized design with four replicates were studied. The grass was cut at 60 days of age, chopped, and ensiled, reaching a packing density of 600 kg/m³. After 28 days of ensiling, the silos were opened and samples were collected for laboratory analysis. Addition of DPB promoted a linear increasing effect on the silages dry matter and a linear decreasing effect on the propionic acid levels. A quadratic effect with maximum point of the DPB increasing levels on the silages lactic acid levels was verified. The butyric acid levels were negligible. The pH values, N-ammonia, acetic acid, and the acid detergent fibre levels were not affected. A linear effect of the DPB increasing levels was verified on the crude protein and the ether extract concentrations. A linear decreasing effect of the DPB increasing levels on the silages NDF and hemicellulose concentration was observed. The DPB addition up to the level of 14% (on a grass fresh matter basis) at the elephantgrass ensiling promoted a good fermentative pattern and a better silage chemical composition.
acid detergent fiber; crude protein; N ammonia; neutral detergent fiber; pH