Abstract
In 1982 to 1984, 3 cases of Pseudomonas anguilliseptica infection occurred in pond-cultured ayu, Plecoglossus altivelis, in Shizuoka Prefecture. The outbreaks of the disease have been reported exclusively in eels, thus this is the first record of the infection in ayu fish.
Biochemically, the isolates from diseased ayu were identical to P. anguilliseptica isolates from eels (Anguilla japonica and A. anguilla). However, the ayu-isolates were proved different from eel-isolates in the pathogenicity to ayu and Japanese eel, resistance to bactericidal action of normal fish sera, and a surface antigen.
