Objective: This study has been conducted in order to determine the effect of cumin essential oil on fermentation quality, aerobic stability, vitro metabolic energy contents and relative feed value vetch-oat silages. Material Methods: Vetch oat were harvested May wilted for approximately 3 hours. Cumin was added silages at CMN2:200 mg/kg, CMN3:300 mg/kg CMN5:500 levels, while no addition made co...