Gut Microbiota Analysis and Comparison in Forest Musk Deer (Moschus berezovskii) of Different Ages and Musk-Secreting Periods.

Under homeostatic conditions, the gut microbiota are closely associated with host health, undergoing co-evolution with the host through complex interactions to maintain mutually beneficial symbiosis. However, dynamic changes in the gut microbiota of forest musk deer (Moschus berezovskii; FMD) at different age stages and musk-secreting periods remain unclear. In this study, we analyzed the fecal microbiota of FMD using metagenomic sequencing across four age groups (subadult, young adult, adult, and old) and four musk-secreting period groups (before musk-secreting period, during musk-secreting period, after musk-secreting period, and musk collection). The results showed that the gut microbiota structure of FMD demonstrated stability across different age stages and musk-secreting periods and was dominated by Firmicutes. Moreover, changes in musk-secreting periods had a greater effect on the gut microbiota of subadult and old FMD, while age-associated differences in gut microbial composition were mainly evident during AMSP. LDA effect size (LEfSe) and STAMP analyses further revealed significant age-associated and musk-secreting period-associated differences in the structure and function of the gut microbiota in FMD. In addition, subadult FMD showed enhanced immune response-associated and potential pathogen-associated functions during musk collection, accompanied by the enrichment of potential opportunistic pathogenic bacteria, suggesting that musk collection may be associated with host stress responses and gut microecological disturbance. In summary, this study explored the relationships among age stages, musk-secreting periods, and gut microbiota of FMD, providing a certain strategic reference for the healthy captive breeding of FMD and the improvement of musk production.