Metagenomic characterization of potential exposure to genetic hazards at the interface between grazing livestock and...

Livestock and endangered wildlife increasingly share grazing landscapes, yet the sources, mobility-associated contexts, and bacterial hosts of livestock-associated genetic hazards in wildlife microbiomes remain poorly resolved. We analyzed metagenomes from yak, Tibetan sheep, Przewalski's gazelle, and local topsoil within an Acquired Genetic Risk (AGR) conceptual framework integrating genetic hazard burden, compositional source attribution, mobility-associated evidence, and bacterial genomic context. MRGs and Rank I and Rank III ARGs were more abundant in livestock than in Przewalski's gazelle, whereas VF abundance was highest in yak. FEAST attributed approximately 64% of the Przewalski's gazelle resistome composition to the two livestock source profiles, less than 1% to sampled topsoil, and approximately 36% remained unassigned. MGE profiles were associated with ARGs, MRGs, and VFs, while tnpA ranked highest in random forest models and was associated with total ARG abundance (R² = 0.618). Short-read contigs containing hazard genes and MGE markers provided localized mobility-associated sequence context. Genome-resolved analysis identified distinct bacterial contexts: TS.Bin143, an Escherichia coli MAG from Tibetan sheep, contained ARGs, MRGs, VFs, tnpA, and IS91, whereas PG.Bin275, a Hylemonella sp. MAG from Przewalski's gazelle, contained tnpA. These findings extend wildlife resistome assessment beyond abundance profiling toward source attribution, mobility-associated sequence context, and bacterial host resolution, supporting multilevel surveillance of genetic hazard exposure at livestock-wildlife interfaces.