Effect of pineapple peel addition on sorghum ensilage

Abstract

Silage mixed with forage and byproducts is an alternative nutritional strategy for ruminant production. This study aimed to characterize chemical–nutritional aspects, fermentative profile, and digestibility of sorghum (Sorghum bicolor L. Moench) silage with different contents of pineapple (Ananas comosus L. Merr.) peel inclusion at 0%, 20%, 40%, 60%, or 80% of fresh matter. The experimental design was completely randomized with five replicates per treatment. Mixed feeds were ensiled in experimental silos for 65 days, subsequently opened, and samples were analysed. The increase in the proportions of pineapple peel caused a linear increase in dry matter, crude protein, mineral matter, ether extract, soluble carbohydrate, cellulose, lignin, and in vitro digestibility of dry matter in sorghum silage. The mean concentrations of neutral detergent fibre (NDF) and acid detergent fibre (ADF) had a negative quadratic relationship with the inclusion of pineapple peel, reducing from 0% to 40% (-2.56% for NDF and -3.14% for ADF) followed by stabilization at subsequent contents. Silage pH was not influenced, however, acetic and propionic acids increased linearly, while butyric acid decreased linearly with pineapple peel inclusion. The highest losses in gases and effluents were obtained in silage with 0% pineapple peel inclusion (1.77% of dry matter and 4.06 kg t-1 of dry matter), which resulted in lower dry matter recovery (93.56%). Adding pineapple peel to sorghum benefits composition, fermentation, in vitro digestibility, and decreases silage losses. An inclusion of 40–80% sorghum can be recommended.