Viral metagenomic profiling of the giant panda and sympatric species at the wildlife livestock interface in Liziping National Nature Reserve, China

This study conducted a deep metagenomic characterization of the virome at the interface between endangered giant pandas (Ailuropoda melanoleuca), sympatric wildlife, and domestic animals within the Liziping National Nature Reserve, Sichuan, China. A total of 95 fecal samples from 13 mammalian species were collected and used to generate 167 metavirome libraries (82 DNA and 85 RNA). Bioinformatics analysis identified 661,837 viral operational taxonomic units (vOTUs), of which >95% represent previously uncharacterized "viral dark matter." Comparative analysis revealed distinct community structures: the DNA virome was more constrained by host phylogeny, while the RNA virome exhibited high ecological plasticity, with notable cross-species transmission signals in families such as Retroviridae and Picornaviridae. A "Source-Bridge-Sink" transmission model was proposed, where domestic animals act as viral reservoirs, sympatric wildlife (e.g., wild boars, cervids) serve as ecological bridges, and giant pandas function as sinks for viral spillover. This work provides a systems-level understanding of viral dynamics and spillover risks for endangered species in human-dominated landscapes.