Fasting and Refeeding Affect the Goose Liver Transcriptome Mainly Through the PPAR Signaling Pathway

Nutrition and energy are essential for poultry growth and production performance. Fasting and refeeding have been widely used to study the effects of nutrition, energy, and related mechanisms in chicken. Previous studies have shown that geese have a strong capacity for fat synthesis and storage; thus, changes in the goose liver transcriptome may be different from those in chicken assessed with a model of fasting and refeeding. However, the responses of the goose liver transcriptome to fasting and refeeding have not yet been addressed. In this study, 36 70-day-old Si Ji geese with similar body weight were randomly assigned to three groups: control (ad libitum feeding), fasting (fasted for 24 h), and refeeding (fast for 24 h followed by 2-h feeding) groups. After treatment, eight geese per group were sacrificed for sample collection. Liver samples from four geese in each group were subjected to transcriptome analysis, followed by validation of differentially expressed genes (DEGs) using quantitative polymerase chain reaction with the remaining samples. As a result, 155 DEGs (73 up-regulated) were identified between the control and fasting groups, and 651 DEGs (321 up-regulated) were identified between the fasting and refeeding groups. The enrichment analyses of Gene Ontology terms and Kyoto Encyclopedia of Genes and Genomes pathways showed that fasting mainly influenced material metabolism in the liver, especially lipid metabolism; in contrast, refeeding affected not only lipid metabolism but also glucose and amino acid metabolism. In addition, the peroxisome proliferator-activated receptor (PPAR) signaling pathway may play an important role in lipid metabolism. In conclusion, fasting and refeeding have a strong effect on lipid metabolism in the goose liver; specifically, fasting promotes fatty acid oxidation and inhibits fatty acid synthesis, and refeeding has the opposite effect. The model of fasting and refeeding is suitable for goose nutrition studies.