養殖チダイから分離された病原性?EＥｄｗａｒｄｓｉｅｌｌａ?Fの性状

Abstract

From late summer to early winter in 1974, an epizootic occurred among cultured crimson sea breams, Evynnis japonicus, in Mie Prefecture. The disease was characterized by the presence of numerous bacterial colonies as grayish white spots in the spleen (Fig. 2) and the kidney. Generally, hemorrhagic ulcers appeared on the head, especially in the opercular region, and body surface (Fig. 1). The causative organisms isolated from the kidney were Gram-negative rods. On BHI agar colonies developed within 24 hours at 25°C. The organisms were nonmotile. IMViC reactions were (++--). Hydrogen sulfide was produced abundantly from TSI agar. The organisms lacked phenylalanine deaminase and urease. Gelatin was not liquefied. Lysine and ornithine decarboxylases were present. Alginate was not utilized. Acid and gas were produced in glucose, fructose, mannose, galactose, maltose, mannitol; acid from arabinose and sorbitol were produced later. Other carbohydrates were not utilized. In KAUFFMANN-PETERSON's broth, the organisms formed weak acids from citrate and d-tartrate. They grew in KCN broth. Catalase positive and oxidase negative. On the basis of the above characteristics, the organisms were identified as a variant of Edwardsiella tarda.