Invasive Species Compendium

Detailed coverage of invasive species threatening livelihoods and the environment worldwide

Abstract

Pathogenicity and culture studies comparing the Aphanomyces involved in epizootic ulcerative syndrome (EUS) with other similar fungi.

Abstract

Zoospores of 58 fungal isolates were injected intramuscularly in snakehead fish, Channa striata (Bloch). The isolates comprised: Aphanomyces strains isolated from EUS-affected fish; saprophytic Aphanomyces, Achlya and Saprolegnia spp. from infected waters; and further saprolegniaceous fungi involved in other diseases of aquatic animals. Only the Aphanomyces strains isolated from fish affected by EUS, Australian red spot disease (considered synonymous with EUS) or mycotic granulomatosis were able to grow invasively through the fish muscle and produce distinctive EUS lesions. In contrast to A. astaci Schikora, the EUS-Aphanomyces was unable to infect noble crayfish, Astacus astacus. The snakehead-pathogenic strains were further distinguished from all the other fungi under comparison by their characteristic temperature-growth profile and inability to grow on certain selective media.