Mechanism of High-Fat Diet Regulating Rabbit Meat Quality Through Gut Microbiota/Gene Axis

With the improvement of living standards, people's awareness of health care is becoming stronger and stronger. Rabbit meat is a very high-quality and healthy meat, but its consumption is low due to its poor flavor. To explore the regulatory mechanism of nutrition on the meat quality of rabbits, twenty-four rabbits were fed a control diet or a high-fat (5 percent lard) diet over 15 days. The contents and tissues of the jejunum were subjected to 16S sequencing and mRNA transcriptome sequencing, respectively. The results indicated that there were significant differences in species diversity through beta diversity analysis (p < 0.05). The diversity of alpha in the experimental group was also significantly reduced (p < 0.05). Based on gene function annotation, 8 bacteria at the phylum level and 11 bacteria at the genus level that are related to the metabolism of adipose tissue showed significant differences between the two groups (p < 0.05). The transcriptome results of the jejunum showed significant differences in 135 genes between the experimental group and control group (p < 0.05). Gene annotation revealed 10 differentially expressed genes related to fat metabolism, which regulate 36 signaling pathways. We speculated that Alloprevotella may influence drip loss and cooked meat rate by changing the expression of PHGDH through correlation analysis. In addition, Coprococcus may influence IMF by changing the expression of NEDD4, ANGPTL3, and CYP8B1. These results indicated that a high-fat diet changed the species and composition of bacteria in the rabbit jejunum. Alloprevotella and Coprococcus may influence rabbit meat quality and flavor by changing PHGDH, NEDD4, ANGPTL3, and CYP8B1 gene expression in the host. This study laid a molecular foundation for the improvement of rabbit meat quality through nutritional diets.