oral anus soil  metagenome
Oral samples: we utilized cotton swabs moistened with sterile saline to wipe the palate, tongue, inner buccal mucosa and dental surfaces of the rats' mouths. Anus samples: we collected anus samples from 2.00 cm into the anus by cotton swabs. Soil samples: we collected the surface soil under the carcasses depth less than 1.00 cm.