Microbiota transplantation and multi-omics profiling integration unveil the mechanism of Alistipes communis-driven abdominal fat deposition in chickens

Abstract Background Emerging evidence highlights strong correlations between the cecal microbiome and abdominal fat deposition (AFD) in chickens. However, the specific microbial species driving this process remain unclear. This study aims to identify the key microbe and elucidate its underlying mechanism in regulating chicken AFD. Results First, cecal microbiota transplantation confirmed a causal relationship between the cecal microbiota and AFD. Subsequently, metagenomic and metatranscriptomic integrations identified Alistipes communis as a key microbe implicated in AFD. Finally, in vivo gavage integrated with multi-omics revealed that A. communis enhances AFD by disrupting host tryptophan and histidine metabolism. This was evidenced by the elevated concentrations of amino acid metabolism-related metabolites, including L-phosphoarginine and spermine in the cecum. Conclusions This study provides direct evidence that the cecal microbiome serves as a key driver in chicken AFD and identifies A. communis as a critical AFD regulator, offering valuable insights into the gut microbiome’s role in host obesity.