Characteristics of Two Saprolegnia Species Isolated from Coho Salmon with Saprolegniosis

Abstract

Several fungi have been isolated from the lesions of coho salmon Oncorhynchus kisutch that have saprolegniosis. Of these fungi, one that occurred frequently was identified as Saprolegnia parasitica strain H2 (=S. diclina type 1). A much rarer fungus was identified as S. diclina strain H3 (=S. diclina type 3). This article describes the pathogenicity of the isolates to coho salmon and the relationship of pathogenicity to the lengths of the isolates, hooked hairs.