Vibrio sp. as a Cause of Disease in Rainbow Trout Cultured in Japan-II
Physiological Characteristics and Pathogenicity
1977 Volume 12 Issue 1 Pages 51-55
Details
1977 Volume 12 Issue 1 Pages 51-55
In the previous report, the biochemical characteristics of 22 strains of a vibrio isolated from diseased rainbow trout were presented (OHNISHI and MUROGA 1976).The organism differs from Vibrio anguillarum in some biochemical characters, and it was given a tentative name of Vibrio sp. RT group.
In this paper, physiological characteristics and pathogenicity of the organism are described.
The experimental results are summerized as follows.
1) Effects of sodium chloride, temperature and pH on the growth of the organism: It grew in broth (1% peptone +1% heart extract) at NaCl 0.5-5% (optimum range 1-3%), at temperatures 15-30°C (optimum 20-25°C), and at pH 6-9 (optimum 7), respectively.
2) Pathogenicity: The organism injected intramuscularly killed rainbow trout and carp.
However, it did not kill mice by intraperitoneal injection.
3) Survivalin waters: The organism survived in sea water more than 4 weeks, but it perishedin freshwater within a few hours. And it is assumed that the organism can not be established in freshwater.
4) From the facts that trout farms investigated are isolated far from sea and these trout have been fed only on dry pellet in recent years, it is thought that some carrier including trout itself must participate in outbreaks of this vibriosis in trout farms.
