Optimization of dietary lemon seed essential oil to enhance alfalfa silage chemical composition and in vitro degradability

Abstract

Purpose of the experiment was to evaluate the effect of lemon-seed essential oils on chemical composition and in vitro degradability of alfalfa silage. Treatments were alfalfa silage with no additive (control) or treated with 60 ml kg-1 DM of lemon-seed (LEO60), of lemon-seed (LEO120) essential oils and equal mixed of them (M60). Whole plant alfalfa silage was ensiled for 60 d in triplicate laboratory scale tubes. Dry matter, organic matter, crude protein, insoluble fiber in acidic and neutral detergent, water soluble carbohydrate, pH, were measured with 3 replicates by in vitro gas production method. Dry matter (DM) content was greater for LEO60 than control. Compared with control, neutral detergent fiber (NDF) concentration was decreased in LEO120. Addition of essential oils and their combination to the silage significantly decreased (p < 0001) silage pH compared with untreated silage interestingly increased for all the silages containing essential oil compared with untreated silage. Addition of lemon-seed essential to alfalfa silage decreased the rate of disappearance of organic matter and dry matter in all treatments compared to the control treatment. The degradability potential of alfalfa silage has increased in treatments containing lemon-seed essential oil (60 ml kg-1 DM) which is significantly different from the control. In general, the obtained data show the positive effect of lemon-seed essential oil on the quality of alfalfa silage and its fermentation properties.