Gene-centric metagenomic analysis of feline fecal microbiome reveals resemeblance to chicken and opportunistic zoonotic agents

The feline fecal microbiota plays an important role not only to animal health but also to human health as a reservoir for potential zoonotic pathogens and antibiotic resistant strains. In order to characterize the fecal microbial community and its functional capacity in domestic cats, we performed this study as the pioneer to use gene-centric metagenomic approach. Pooled fecal DNA samples from five healthy household cats were subjected to pyrosequencing. 454 GS junior system generated 152,494 pyrosequencing reads (total of 5,405 contigs) which have been classified to both phylogenetic and metabolic diversity of feline fecal microbiota. The Bacteroides/Chlorobi group is the most predominant bacterial phyla comprised ~68% and followed by Firmicutes (~13%) and Proteobacteria (~6%) respectively. Archaea, fungi and virus were minor community in overall diversity. Different from other metagenomes, three functional catagories such as dormancy and sporulation, macromolecular synthesis and secondary metabolism were depleted. Interestingly, this study also provided the diversity of enteric zoonotic pathogens (0.01-2.5%) as well as genes involved in antimicrobial resistant mechanisms. According to the similarity and distances based clustering among nine gastrointestinal metagenomes from five different hosts, cat metagenome clustered closely together with chicken both in phylogenetic level and in metabolic level (>80%). Future studies are required to provide deeper understanding on both intrinsic and extrinsic effects such as age, genetics and dietary interventions in feline gastrointestinal microbiome.