IFIT5 and viral infectious disease: Several of the most highly differentially expressed genes in the poly I:C treatment (Fig. 3a) are interferon stimulated genes (ISGs) that are activated during viral infections in ducks, including viperin (RSAD2), IFITM1 (Interferon induced transmembrane protein 1), IFIT5 (Interferon induced protein with tricopeptide repeats 5) and OASL (2′–5′ oligoadenylate synthetase-like)43.