Abstract: This study aimed to explore the molecular mechanism by which the liver regulates the absorption and conversion of nutrients and affects the body weight of goose. RNA-Seq technology was used to analyze the RNA expression in livers of Sichuan White goose with different average daily gain (high:H; middle:M; low:L) at 70-days-old. The differentially expressed genes were screened, their functional enrichment and cluster correlation analysis were performed. The results showed that the average daily gain of the H, M, and L groups were significantly different (P<0.05), which were (52.24±0.41), (44.44±0.42), and (37.80±0.47) g·d^-1, respectively. There were 14 632, 14 651 and 14 819 expression genes identified, of which 13 776 genes were co-expressed. The expression level of the top 100 genes accounted for 65.38%-70.37% of all gene expression, including 85 co-expression genes and 17 specific expression genes. Four hundred thirty five differentially expressed genes were identified, and mainly enriched in apoptosis, protein refolding, insulin secretion, nutritional response, cell growth, amino acid transport, and cAMP signaling pathway. The 5 gene modules constructed from differentially expressed genes were significantly associated with average daily gain and lipid metabolism index (|r|≥ 0.75, P<0.05). Overall, body weight related potential candidate genes and metabolic pathways were identified. The molecular mechanism by which the liver regulates nutrient absorption and conversion and affects the weight of goose was explored, which make us better understand how liver metabolism affects the weight of goose and can help us to design new selection strategies to improve goose production.

Key words: goose, body weight, liver, transcriptome, function