Microbial diversity of laying hens

The dominant microbiota in caecum of laying hens was Firmicutes (46.28%), Bacteroidetes (44.09%), Proteobacteria (3.28%), and Actinobacteria (2.11%) at the phylum level. The dominant taxa were conserved and not affected by dietary supplement. However, the relative abundance of the dominant taxa was affected by this factor. In the cecum, microbial diversity of the dietary PB group was significantly higher than that of the CT group (P<0.05). The relative abundance of the Faecalibacterium, Firmicutes and the ratio of Firmicutes/Bacteroidetes was increased in laying hens treated with TP (P<0.05). Additionally, PB decreased the relative abundance of Rikenellaceae_RC9_gut_group at genus level (P<0.05). And the functional prediction of gut microbiota indicated TP and PB treatment could inhibit the glycine, serine and threonine metabolism (P<0.05). Analysis of microbial community-level phenotypes revealed significant differences in two phenotypes (anaerobic and potntially pathogenic) between PB group and CT group (P<0.05).