Impact of Long-Term Storage on Alfalfa Leaf and Stem Silage Characteristics

Abstract

Fractionation of alfalfa (Medicago sativa L.) into leaves and stems can reduce cutting frequency while producing a high-value feedstuff. A difficulty with fractionation is the higher moisture content at ensiling due to the inability to wilt leaves without substantial dry matter loss or financial cost. To evaluate whether the silage quality of fractionated alfalfa is competitive with conventional methods under long-term storage conditions, high-moisture leaves (250–280 g·kg−1 dry matter, DM) and stems (190–240 g·kg−1 DM) were ensiled for 21 and 350 days and compared to wilted whole-plant silage for two alfalfa developmental stages. At 21 days, leaf and whole-plant silage fermentation characteristics indicated suitable lactic acid bacterial fermentation through decreased pH, high lactic acid–to-acetic acid ratio, and a lack of clostridial fermentation. At 350 days, leaf silage fermentation and nutritional quality decreased due to sustained proteolysis, but true protein still exceeded that of whole-plant silage. High-moisture stem fractions fermented poorly; at 21 days, stage 3 stems had significant amounts of butyric acid, while stage 5 stems became clostridial at 350 days. Long-term storage of high-moisture leaf silages can produce good-quality silage despite exceeding moisture contents typically recommended for alfalfa, while wilting is required for stem silages.

The Effect of Lactobacillus planturum YQM48 Inoculation on the Quality and Microbial Community Structure of Alfalfa Silage Cultured in Saline-Alkali Soil

“…The abundance of L. plantarum can reduce the ammonium nitrogen content in silage feed [34]. Longer fermentation times increase the abundance of lactobacilli, and the acidic environment they create reduces the propagation of miscellaneous and mold microorganisms [35], as observed in our study. The reduced Shannon index of microbial community during inoculated fermentation suggests that silage additives can reduce the diversity and richness of bacterial communities [36].…”

Diversifying the utility and species composition of Nordic forage systems : new fractionation methods and novel legume species

“…The leaf fraction has been shown to have potential as an energy feed source for monogastrics, due to the high concentration of easily digestible carbohydrates . The preservation of the leaf fraction through drying or ensiling can ensure the availability of protein-rich feed throughout the year Sikora et al, , 2021. The remaining stems can subsequently be harvested using conventional harvest machinery.…”