Abstract:

This study aims to elucidate the potential mechanisms of yeast supplementation in diets for laying hens to improve their production performance and solve the problem of unclear yeast working mechanism using transcriptomics and genomics technologies. Compared to the basal diet group, yeast supplementation in laying hen diets increased the Chao and Shannon indices of the cecal microbiota (P>0.05). At the phylum level, the relative abundance of Bacteroidetes and Firmicutes increased in the yeast-supplemented group (P>0.05). At the genus level, the relative abundance of Bacteroides, Lactobacillus, Parabacteroides distasonis, Prevotella, Ruminococcus, Faecalibacterium, and Phascolarctobacterium also increased (P>0.05). Additionally, the relative abundance of Rikenella was significantly decreased compared to the basal diet group (P≤0.05). Transcriptomic analysis revealed that 329 genes were differentially expressed in ileal mucosal tissues, with 184 genes upregulated and 145 genes down regulated. These changes together improved the absorption and utilization efficiency of nutrients in diets for laying hens. This study revealed the molecular mechanism of yeast in improving the diets utilization rate of laying hens by regulating the structure of cecal microbiota and the expression of key genes in ileum mucosa, which provided a theoretical basis for the application of yeast as a green and safe new antibiotic substitute.

Key words: laying hens, yeast, genomics, transcriptomics, production performance