An Ecological Study on Edwardsiella tarda in Flounder Farms

Rashid M. Mamnur

Honda Kazumitsu

Nakai Toshihiro

Muroga Kiyokuni

魚病研究

Fish Pathology

An ecological investigation on Edwardsiella tarda was carried out in two Japanese flounder (Paralichthys olivaceus) farms in Fukuyama City from April to December 1992. E. tarda was isolated from 86% of water, 44% of sediment and 14% of fish samples in one pond, and 22% of water, 0% of sediment and 2% of fish samples in the other pond, although epizootics caused by E. tarda were not observed in either pond. Serological studies proved that all the isolates of E. tarda from flounder and its environment shared a common heat stable O-antigen. Almost all the isolates tested exhibited pathogenicity to flounder by intramuscular injection. In survivability tests of selected isolates in sea water and freshwater, they perished within 7 days in sea water but survived longer period in freshwater.

These results suggest that there is only one serotype of E. tarda which has pathogenicity to flounder in the environment of flounder farms.

水産業 [ 660 ]

英語

日本魚病学会

[ISSN] 0388-788X

[NCID] AN00063165