Fermentation dynamics and diversity of bacterial community in four typical woody forages

Abstract

Woody forage is a new feeding resource used worldwide, and silage is the main long-term storage, mediated by micro-organisms present during their processing. The objectives of our work were to evaluate the fermentation dynamics and to characterize the bacterial community of our typical woody forages. We selected four typical woody forages: paper mulberry (Broussonetia papyrifera), mulberry (Morus alba L.), moringa tree (Moringa oleifera), and Anthocephalus chinensis (Neolamarckia cadamba). The materials were ensiled and sampled after ensiling 1, 3, 5, 7, 15, 30, and 60 days. Our results indicate that woody forages have good forage properties with relatively high crude protein content and low neutral detergent fiber and acid detergent fiber content. However, the water soluble carbohydrate content in paper mulberry was considerably low (18.67 g kg−1), which makes ensiling difficult. The lactic acid and acetic acid contents in each of the four materials were reduced after 3 days of ensiling and increased again after 30 days of ensiling, with the exception of Anthocephalus chinensis. Anthocephalus chinensis and moringa tree were well-preserved after 7 and 60 days of ensiling, respectively, with low pH and ammonia nitrogen content. Cyanobacteria was predominant in moringa tree and Anthocephalus chinensis before ensiling, and Lactobacillus became dominant after 15 days of ensiling. Enterobacter dominated the paper mulberry and mulberry during fermentation process and accelerated their poor silage quality. Therefore, the conformity of bacterial community succession with ensiling parameters guaranteed the final quality of woody forage silages, and this might aid in controlling the manufacturing process.