Preservation of Fungal-Treated Cowpea Straw in Association with Discarded Apple by Ensilage Process

The available agroindustry residues show high potential to be used as animal feedstuffs. This study aimed to valorise cowpea straw and discarded apple as potential ingredients for livestock diets through an ensiling process. Silage characteristics of cowpea straw (15%, as fresh) treated with Pleurotus citrinopileatus in association with discarded apple using or not a commercial inoculant were evaluated. At the moment of opening the silo, silages were stable and presented low pH values (≤ 4.2), high lactic acid concentration, no butyric acid, and aerobic stability averaged 134 h. The inoculated silage presented higher (p < 0.01) neutral detergent fibre, water-soluble carbohydrate (WSC), lactic acid and ethanol, but lower (p < 0.01) acetic acid concentrations. The use of the commercial inoculant increased the amount of lactic acid bacteria in the pre-mixture and at the time of opening the silo. No differences were observed in enterobacteriaceae, yeast and moulds count in both treatments until 288 h of air exposure. The pre-ensiled mixture showed a high ensilability potential, and the utilization of a silage inoculant enhanced the silage fermentation process promoting changes on the silage microflora. Graphic Abstract