Endobiotic infusoria of the snow sheep found in Yakutia

A study of the contents of the gastrointestinal tract of the wild snow sheep in different regions of Yakutia revealed a significant diversity of endobiont infusoria, which play an important role in the digestion of this animal. Twelve species of infusoria belonging to the genera Entodinium, Eudiplodinium, Polyplastron, Metadinium, and Ophryoscolex were identified, including three new species distinguished by their morphology and description. The symbiotic fauna varied depending on the geographical location of the snow sheep populations; for example, 11 species were found in the Eveno-Bytantay ulus and 7 in the Oymyakon ulus, with seven species being common to both populations. An interesting observation is that the efficiency of snow sheep digestion directly depends on the fermentative activity of specific infusoria species, similar to other large herbivorous animals in Yakutia. Infusoria demonstrate the ability to survive for extended periods in winter conditions, which is crucial for digesting coarse plant food available in this harsh environment. This study emphasizes the importance of the interaction between microorganisms and their hosts for optimizing digestion and survival in the extreme Siberian climate. Further research in this direction could significantly contribute not only to the preservation of biodiversity but also to the development of new approaches in veterinary medicine and ecology. The discovery of three new species of infusoria aims to enrich the database of microorganisms and may represent an important step toward understanding biological adaptations to the harsh conditions of Yakutia. Understanding this interaction may have long-term implications for the management of wild animal populations, especially in the context of climate change and biodiversity conservation.