title: Metagenome of samples from pig feces and oral swab
design: To conduct viral screening, samples were diluted in a tenfold volume of phosphate-buffered saline (PBS) and subjected to intense vortexing for a duration of 10 minutes. The resulting supernatants were isolated through a centrifugation process at 15,000  g for 15 minutes. Then, viral metagenomic next-generation sequencing (NGS) was conducted.The procedure began by filtering 500L of each samples supernatant through a 0.45m membrane filter to effectively remove large contaminants such as eukaryotic cells and bacteria. Subsequently, the filtrate was incubated at 37C with a combination of DNase and RNase enzymes for 60 minutes to ensure complete degradation of any unprotected free nucleic acids. Following enzymatic treatment, the remaining nucleic acids were extracted using the QiaAmp Mini Viral RNA Extraction Kit[13-14].During the cDNA synthesis process, first-strand cDNA was generated using the SuperScript III First-Strand Synthesis System, and the second strand was synthesized using Klenow fragment DNA polymerase. Thereafter, three independent libraries were constructed using the XT DNA Sample Preparation Kit and sequenced on the Illumina HiSeq platform, each employing a dual-barcoding strategy.