Effects of browse legume species addition on nutritional composition, fermentation characteristics and aerobic stability of Opuntia cladodes silage

Abstract

Forage legumes are commonly used as an absorbent additive in high-moisture silages. Thus this study was carried out to assess the nutritive value, fermentation characteristics and aerobic stability of Opuntia–legume browse mixed silages. Five browse legume species (Leucaena leucocephala, Acacia mellifera, Searsia lancea, Prosopis velutina, and Grewia flava) were mixed with Opuntia cladodes. The silage mixture was formulated at a ratio of 60 Opuntia cladodes: 40 leguminous browse species and ensiled in polythene bags and kept in a laboratory for 42 days to determine chemical composition and fermentation characteristics. Silage samples were also subjected to an aerobic stability test. One-way analysis of variance in a completely randomised design was used to analyse the data. The pH values for silages made from Opuntia cladodes with L. leucocephala, A. mellifera and G. flava were lower than 4.8, which is considered an indicator of good-quality silage. The water-soluble carbohydrates content of silages made with Opuntia cladodes and S. lancea and G. flava was within the range of 8–12 g/kg dry matter, which is sufficient for good fermentation. The highest CO2 production, which signifies poor aerobic stability, was recorded for the control silage (Opuntia) compared to all Opuntia–legume mixed silage treatments. The addition of legume browse leaf-meal to Opuntia cladodes improved nutritive value, fermentation characteristics, and silage quality. Therefore, despite some limitations, Opuntia–legume browse silages, particularly Opuntia–G. flava and Opuntia–L. leucocephala, proved to be beneficial for livestock, as they meet the nutritional requirement of a ruminant. Significance:This study underlines the importance of co-ensiling Opuntia cladodes and high protein legume browse hay to offer an alternative feeding strategy for ruminant livestock and ensure sustainable provision of high-quality feed during dry periods.