Enrichment Analysis of Differentially Expressed Genes During Feather Regeneration in Landes Geese ( <scp> <i>Anser anser</i> </scp> )

Feathers are valuable by-products of the poultry industry, and their growth and development markedly have significant impact on economic returns. This study used Landes geese as a model to analyze the expression of core genes involved in feather regeneration and inflammation through comparative transcriptomic analyzes between plucked and unplucked skin tissues. In Landes geese aged 180 days (LD180), 624 differentially expressed genes (DEGs) were identified at 5 days post-plucking (481 upregulated and 143 downregulated), whereas 1851 DEGs were identified at 14 days (1350 upregulated and 501 downregulated). In Landes geese aged 90 days (LD90), 694 DEGs were detected at five days post-plucking (513 upregulated and 181 downregulated), with 1154 DEGs identified at 14 days (887 upregulated and 267 downregulated). These DEGs were significantly enriched in GO terms, KEGG pathways, and protein-protein interaction networks associated with inflammatory responses (e.g., leukocyte-mediated immunity), and feather regeneration (e.g., epidermis development). Notably, signatures of both innate and adaptive immunity were detected at the early post-plucking stage. Compared with younger geese, the LD180 group showed faster inflammatory resolution than the LD90 group, as demonstrated by a more pronounced decrease in proinflammatory gene expression levels in LD180. Comparative analysis revealed that mechanical damage (such as feather plucking) induces immediate inflammatory and anti-inflammatory responses. In conclusion, the mechanical damage caused by feather plucking triggers a renewed cycle of feather growth, which requires overcoming the harm inflicted by the subsequent inflammatory responses. The ability to recover from inflammatory damage varies significantly with age.