A competitive-ELISA for the serodiagnosis of anguillicolosis in Japanese eel, Anguilla japonica

Anguillicolosis is a parasitic disease of eel caused by infection with swim bladder nematode, Anguillicola crassus. This study aims to establish a sero diagnosis method for anguillicolosis. A competitive ELISA with an anti-Onch ocerca volvulus mouse monoclonal antibody (No. 107) was applied to detect t he specific antibodies against A. crassus in eel sera, using various captur e antigens for ELISA. Infected eel sera showed a higher competitive reactio n to the cuticle antigen of A. crassus than non-infected eel sera. The posi tive detection rate of infected eel sera and the false positive rate of non -infected eel sera were calculated as 95% and 0%, respectively. When an ind irect ELISA with polyclonal rabbit anti-eel IgM antibodies was performed, t he positive detection rate and the false positive rate were 80% and 20%, re spectively. The competitive ELISA technique provided a more sensitive and s pecific serodiagnostic tool than the indirect ELISA for detecting A. crassu s infection in eels.