Flacherie-induced microbial dysbiosis reshapes the gut ecosystem of Antheraea assamensis (muga silkworm)

Abstract

The gut microbiota plays a vital role in insect health, development, and disease resistance. In this study, we analyzed the gut bacterial community of Antheraea assamensis (muga silkworm) larvae showing symptoms of flacherie, a disease causing heavy losses in sericulture. Using 16S rRNA-based metagenomic sequencing, we identified a diverse bacterial population dominated by the phyla Firmicutes and Proteobacteria. At the genus level, Vagococcus and Enterococcus were the most abundant, followed by Escherichia and Staphylococcus. Alpha diversity measures indicated a rich and balanced microbial community within the infected gut. The dominance of lactic acid bacteria (LAB) suggests possible roles in gut metabolism and pH regulation, while the presence of opportunistic bacteria such as Enterococcus and Escherichia may reflect infection-associated dysbiosis. Although this study analyzed only one infected sample, the findings provide valuable baseline data for understanding microbial shifts during disease and lay the groundwork for future comparative studies with healthy larvae. It could contribute to improving the health and productivity of muga silkworms through better and more efficient microbial management strategies.