Abstract
The porcine gut microbiome is crucial for pig health and key to its production performance. However, genome-level analysis across multiple kingdoms remains limited. Here, we reconstructed the unified pig gastrointestinal genome (UPGG), including bacterial, archaeal, and annotated over 78 million non-redundant protein-coding genes using 5784 metagenome samples. We identified antibiotic resistance genes (ARGs) and mobile genetic elements (MGEs), and the distribution of 72,056 metabolic gene clusters within existing populations. We have constructed pan-genomes of 436 high-quality microbial species and, using these as references, discovered intraspecies genomic variations that revealed 23,350,975 single-nucleotide variants (SNVs). Finally, through comparative analysis of gut microbiome genomes conducted in this study, we observed that pigs may serve as a more suitable model than other animals for investigating human gut microbiota composition and functional patterns. In summary, we constructed a comprehensive reference catalog of the porcine gut microbiome and enhanced the understanding of the host-microbe coevolution.