Transcriptomic Analysis of Domestic Ducks’ Proventriculus Infected with Eustrongylides tubifex (Nitzsch 1819) Jägerskiöld 1909

Gastric nematodes can cause severe diarrheal diseases of waterfowl and threaten waterfowl health and productivity. The immune response mechanism of the host against this parasite is unclear. We investigated the transcriptomic changes, immune related pathways and adaptive molecular responses in infected ducks. RNA sequencing of the gastric tissues of infected and control ducks was followed by differential expression using DESeq2, and functional enrichment and protein–protein interaction networks were constructed. There were 1983 differentially expressed genes (DEGs), including 1317 upregulated genes and 666 downregulated genes. GO and KEGG analyses showed considerable enrichment in immune response, extracellular matrix organization, and chemotaxis and cytokine-mediated signaling pathways, suggesting systemic immune activation and tissue remodeling. The protein–protein interaction network indicated several hub genes that might be central to host defense. Validation by RT-qPCR showed consistent expression trends for some DEGs. These results systematically outline the transcriptomic landscape of ducks infected with Eustrongylides tubifex, offering new insights into host–parasite interactions and immune modulation. The results enhance our understanding of anti-helminth immunity in waterfowl and may inform strategies for disease control in poultry production.