Inhibitory effects of Fucoidan on Muscovy duck-origin parvovirus in vitro and in vivo

Muscovy duck-origin goose parvovirus (MDGPV) is a highly pathogenic viral pathogen that causes severe intestinal embolism and high mortality in Muscovy ducks, posing a substantial threat to the commercial Muscovy duck industry. Here, we investigated the antiviral activity of fucoidan against MDGPV and characterized its underlying mechanisms of action. Using a network pharmacology approach, we identified ten core targets of fucoidan against MDGPV infection, with EGFR emerging as a key candidate. We further confirmed that fucoidan inhibits MDGPV replication in a dose-dependent manner, alongside downregulated EGFR expression and suppressed phosphorylation of core proteins in the MAPK signaling pathway. Conversely, EGFR overexpression enhanced MDGPV replication, and this proviral effect was effectively abrogated by fucoidan treatment. In an in vivo Muscovy duck challenge model, fucoidan administration exerted significant protective effects, as evidenced by improved survival rates and attenuated intestinal pathological injury. Collectively, these findings provide novel insights into the antiviral mechanisms of fucoidan and support its potential as a natural antiviral agent.