Abstract
The pathogenic organisms occurred in cultured marine fishes in Kamak Bay were investigated from March to November in 1993. The samples were collected at 7 sampling stations once a month. Nine species of pathogenic organisms (Vibrio sp., Edwardsiella sp., Flexibacter sp., Streptococcus sp., Micrococcus sp., Caligus sp., Trichodina sp., Lymphocystis and Staphylococcus sp.) were identified as pathogenic organisms from four different species of fish (Sebastes schlegeli, Paralichthys olivaceus, lateolabrax japonicus and Pagrus major) collected in the study areas. Most of pathogenic organisms were found at over 20^{\circ}C$ of sea water temperature from June to October in 1993. On the test of drug sensitivity, Vibrio sp. (KS-9303) was sensitive to oxytetracycline and chloramphenicol ; Edwardsiella sp. (KP-9315) to oxytetracycline ; Flexibacter sp. (KP-9318) to oxytetracycline, chloramphenicol and oxolinic acid ; Streptococcus sp. (KP-9319) to erythromycin, chlorampheicol and oxytetracycline. However, all these 4 isolated bacteria were resistant to ampicilin, steptomycin, sulfamethoxazole and nitrofurazone.
여천군 가막만에서 해산어류의 어병발생은 20^{\circ}C$이상인 시기에 집중적으로 발생하였다. 어종별 병원성생물은 넙치가 Vibrio sp., Edwardsiella sp., Streptococcus sp., Vibrio+Edwardsiella sp., Streptococcus sp.+Microcotyle sp,+Caligus sp. 및 Trichodina sp.에 감염, 조피볼락은 원인 불명 (선회병; 원인생물은 포도상구균으로 1994년에 동정함), 림포시스티스증, , Vibro+Microcotyle sp. 및 Streptococcus sp.+Micrococcus sp.에 감염, 농어는 림포시스티스증, Vibro sp., Vibro+Streptococcus sp. 및 Streptococcus sp.+Microcotyle sp.+Caligus sp.에 감염, 참돔은 Edwardsiella sp.에 각각 감염되었다. 조사지점 7개소 중 1, 5 및 6번 가두리 양식장은 20^{\circ}C$이상인 6월부터 10월까지 연속적으로 어병이 발생하였다. 약제감수성시험에서 Vibrio sp. (KS-9303)는 옥시테트라사이크린, 클로람페니콜, Edwardsiella sp. (KP-9315)는 옥시테트라사이클린, Flaxibacter sp. (KP-9318)는 옥시테트라사이클린, 옥소린산 및 클로람페니콜, 그리고 Streptococcus sp. (KP-9319)는 에리스로마이신, 옥시테트라사이클린 및 클로람페니콜 순으로 감수성이 나타났다.