Research Note: Integrative analysis of transcriptome and gut microbiome reveals foie gras capacity difference between cage and floor rearing systems

To explore the differences in foie gras performance between geese raised in cages and on the ground, we conducted an integrative analysis of liver transcriptome and gut microbial metagenomes. The results showed extremely significant differences in the liver weight (P < 0.01) and liver lipid accumulation of FRS and CRS groups. The levels of triglyceride (TG), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C) of CRS were significantly higher than those of FRS (P < 0.05). Transcriptome analysis showed that 3,917 upregulated and 1,395 downregulated genes were identified, and lipid metabolism pathway and fatty acid metabolism were significantly enriched. Analysis of cecum microbiota revealed that several inflammation-related bacteria (including Gallibacterium, Escherichia-Shigella, Desulfovibrio, Alistipes, and Fournierella) were enriched in CRS, while beneficial bacteria (including Lactobacillus, Limosilactobacillus, and Ligilactobacillus) were significantly enriched in FRS. In conclusion, CRS was better than FRS in foie gras production, which was more conducive to lipid deposition in the goose liver.