Estudio sobre ensilados de pasto kikuyo (Cenchrus clandestinus) como opción forrajera en valles altos de México

Abstract

Background: Kikuyu grass (Cenchrus clandestinus) is a tropical forage adapted to the highlands of Mexico, valued for its high yield, drought tolerance, and low cost. Ensiling allows for the utilization of surplus biomass during the rainy season, and its quality can be improved through wilting and inoculants. Studies on its use as silage in Mexico are limited; thus, assessing its nutritional value is necessary. Objective: To evaluate the chemical composition and nutritional quality of Kikuyu grass silage in relation to the use of additives and pre-wilting prior to ensiling. Methodology: Two experiments were conducted using a 2x2 factorial design in microsilos. Exp. 1 evaluated a bacterial inoculant, molasses (5%), and their combination. Exp. 2 evaluated the inoculant, pre-wilting (24 h), and their interaction. Chemical composition (DM, OM, NDF, ADF, and CP), in vitro dry matter digestibility (IVDMD), pH, fungal growth, and effluent losses were analyzed. Results: In Exp. 1, molasses significantly increased dry matter content but resulted in higher effluent production; it also reduced NDF and ADF, improved IVDMD, and lowered pH and CP. The inoculant reduced both CP and IVDMD; however, molasses counteracted the inoculant's negative effect on IVDMD. Their combination increased fungal growth. In Exp. 2, pre-wilting increased DM, improved IVDMD, and decreased fungal colony counts. The inoculant increased NDF and ADF while reducing IVDMD. The interaction showed that the inoculant only reduced IVDMD in non-wilted silages. Implications: The decision to employ wilting or inoculants must be based on the initial DM content of the forage. Furthermore, evaluating optimal molasses doses is recommended to minimize effluents and maximize benefits. Conclusion: Molasses demonstrated the greatest benefits in fermentation and digestibility, despite the risk of effluents. Additive combinations may have antagonistic effects (e.g., molasses + inoculant on fungal growth). Pre-wilting also improved digestibility.