Fermentative profile, nutritional composition, and aerobic stability of elephant grass (Pennisetum purpureum Schum) and forage peanut (Arachis pintoi) mixed silages

Objective. Determine the fermentative profile, proximate composition, and aerobic stability of mixed silages of elephant grass combined with levels of forage peanut. Materials and methods. Different levels of forage peanut (0.0, 20.0, 40.0, 60.0, and 80.0% on FM basis) were added to elephant grass silages. A completely randomized design was adopted, with 5 treatments and 3 repetitions, totaling 15 experimental silos that were opened after 30 days of sealing. Fermentative profile, proximate composition, and aerobic stability were evaluated. Results. The increase in the forage peanut levels in the elephant grass silages promoted a increasing on porosity, permeability, density, and pH (p<0.001). A 0.58 reduction in Flieg index for every 1% forage peanut added to the elephant grass silage was observed (p<0.001). The sum of the silage temperature difference compared to the environment (p=0.032) and aerobic stability (p<0.001) showed a quadratic effect. The forage peanut inclusion in elephant grass silages reduced the dry matter, organic matter, neutral and acid detergent fiber, hemicellulose, cellulose, and total carbohydrates (p<0.05) and increased the mineral matter, crude protein, lignin, non-fibrous carbohydrates, and total digestible nutrients (p<0.05). Conclusions. Under the experimental conditions, recommend the inclusion of up to 40% forage peanut combined with elephant grass to compose mixed silages, due to the better fermentative dynamic, nutritional profile, and aerobic stability.