The Chicken Gut Metagenome at Different Egg-Laying Stages and Its Correlation With Egg Production Performance

To investigate the investigation of gut microbial communities to chicken egg production performance during different laying stages, we conducted a comparative study of the diversity, composition, and function of microbial communities in the fecal and cecal contents of six hens at the early stage, 25 at the peak stage, and 15 at the late stage. We obtained clean data averaging 13.40 and 13.79 Gb for each of the fecal and cecal content samples. The metagenomic analysis revealed significant differences in fecal and cecal content microbial diversity during different laying stages, especially during the peak stage, and the microbiota structure of fecal contents was more stable compared to that of cecal contents. The dominant microflora in the fecal contents during the peak stage were Firmicutes (74.84%) and Lactobacillus (28.13%). The dominant microflora of cecal contents during different stages were basically the same at the phylum level and genus level. During the peak stage, the dominant bacteria shared by microorganisms in the fecal and cecal contents were Lactobacillus. Functional analyses of the gut microbiome indicate that fecal and cecal content microbes have different functional capacities at different egg-laying stages. We therefore hypothesized that the gut microbiome would vary with laying stage and have a non-negligible effect on egg production performance. These results improved our ability to provide some theoretical basis for feeding management of laying hens during different laying stages and provided insights into the influence of the gut microbiota on the laying performance of chickens.