2022 年 57 巻 1 号 p. 26-29
The location Edwardsiella anguillarum causing edwardsiellosis in red sea bream Pagrus major enters the fish is hypothesized to be the nasal cavity because ulcers form on the head. To test this hypothesis, we conducted two infection experiments on red sea bream. Fish were inoculated with a bacterial suspension in each nasal cavity, the cumulative mortality plateaued at 60–70%. Fish had its nasal cavities obstructed were challenged by immersion infection, the cumulative mortality was significantly lower than control group. These results strongly suggest that the nasal cavity of fish is an important entry site for E. anguillarum.