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

Abstract

Anguillicolosis is a parasitic disease of eel caused by infection with swimbladder nematode, Anguillicola crassus. This study aims to establish a serodiagnosis method for anguillicolosis. A competitive ELISA with an anti-Onchocerca volvulus mouse monoclonal antibody (No. 107) was applied to detect the specific antibodies against A. crassus in eel sera, using various capture antigens for ELISA. Infected eel sera showed a higher competitive reaction to the cuticle antigen of A. crassus than non-infected eel sera. The positive 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 indirect ELISA with polyclonal rabbit anti-eel IgM antibodies was performed, the positive detection rate and the false positive rate were 80% and 20%, respectively. The competitive ELISA technique provided a more sensitive and specific serodiagnostic tool than the indirect ELISA for detecting A. crassus infection in eels.