Monoclonal antibody (MAb) based immunodot for early detection of Aphanomyces invadans in fish

untius sp were injected with 0.1ml spores of Aphanomyces invadans intramuscularly into the left dorsal trunk muscle. Fish were collected at an interval of 1, 3, 5, 10, 24, 48h and 4d after the injection. The muscle tissue was removed from the injection site, away from the injection site, far away from the injection site and other side of the injection site and used for MAb based immunodot and histopathogical observation. The immunodot could detect the fungus at 1h post injection (1hpi) at the injection site, at 3hpi away from the injection site and at 10hpi far away and other side of injection site. Histopathology could detect the fungus at 48hpi in the form of typical mycotic granulomas. The study indicates the high sensitivity of the MAb based immunodot for early detection of the fungus.