Yield and quality of Mavuno grass forage and silage mixed with agro-industrial by-products | Rendimiento y calidad de forraje y ensilado de pasto Mavuno mezclado con subproductos agroindustriales

English. The objective was to evaluate the yield and quality of forage and silage of Mavuno grass at different cutting intervals with the use of additives. Forage yield was evaluated at intervals of 3, 6 and 9 weeks of regrowth, with two additives (orange peel and molasses). The treatments were: 1) Mavuno grass; 2) Mavuno grass + orange peel; 3) Mavuno grass + molasses and 4) Mavuno grass + orange peel + molasses. Dry matter yield (kg ha-1) and nutritional value; content (g kg-1 DM) of crude protein, acid detergent fiber, neutral detergent fiber, lignin; silage quality variables: pH, brix degrees and percentage of dry matter of the forage, were determined by a randomized complete block design. The data were analyzed by analysis of variance and the Tukey test was applied for comparison of means (α = 0.05). When harvesting the forage at nine-week intervals, the dry matter yield was 50 and 45% higher than that obtained in the third and sixth weeks, while the protein content at three-week intervals was 14 and 25% higher than that obtained in the sixth and ninth weeks, respectively. The increase in the cutting interval induced a higher dry matter yield, however, the protein content decreased and the fiber and lignin values increased, while the addition of additives to the ensiled forage improved quality parameters such as protein, brix degrees and dry matter percentage.

Spanish; Castilian. El objetivo fue evaluar el rendimiento y calidad de forraje y ensilado de pasto Mavuno a diferente intervalo de corte con dos aditivos. Se evaluaron intervalos de 3, 6 y 9 semanas y aditivos (melaza y cáscara de naranja). Los tratamientos fueron: 1) pasto Mavuno; 2) pasto Mavuno + cáscara de naranja; 3) pasto Mavuno + melaza y 4) pasto Mavuno + cáscara de naranja + melaza. Se determinó el rendimiento de materia seca (kg ha-1) y el valor nutricional; contenido (g kg-1) de proteína cruda, fibra detergente ácido, neutro, lignina; variables de calidad del ensilado: pH, grados brix y porcentaje de materia seca del forraje. Al cosechar el forraje a intervalo de nueve semanas se obtiene mayor rendimiento de materia seca 50 y 45 % al obtenido en la tercera y sexta semana, mientras que, el contenido de proteína es mayor a intervalo de tres semanas 14 y 25 % al obtenido en la sexta y novena semana, respectivamente. El pasto solo presentó menores valores de proteína y mayores valores de fibras y lignina. El mayor rendimiento de materia seca se obtiene a intervalo de nueve semanas, mientras que, el contenido de proteína disminuye e incrementan los valores de fibras y lignina. Sin embargo, la adición de aditivos al forraje ensilado mejoró parámetros de calidad como proteína, grados brix y porcentaje de materia seca.