我が国の海面養殖ギンマスに発生したビブリオ病原因菌について

• Main Authors: 田島, 研一, 吉水, 守, 絵面, 良男, 木村, 喬久
• Format: Journal Article
• Language: Japanese
• Published: 日本水産学会 = The Japanese Society of Scientific Fisheries 01.01.1981

東北地方および北海道のギンマス海中養殖場においてビブリオ病と思われる病魚より分離した38菌株について検討を行つた結果，1. No. 1～No. 33の33株はV. anguillarumと同定された。また3種のV. anguillarumウサギ抗血清（抗J-O-1，抗J-O-2，抗J-O-3）との凝集反応の結果，すべて抗J-O-3血清と凝集陽性であった。2. V. anguillarumと同定された中からNo. 1株について，菌浴攻撃（約10^5 cells/ml）によりシロサケに対する病原性を検討した結果，いわゆる自然感染魚の症状と類似の症状を呈し斃死した。3. 虻田において分離された5株（No. 34～No. 38）は，vibrio属菌株とは同定されるものの，V. anguillarumとは明らかに異なつた性状を示し，V. anguillarumのいずれの抗血清とも凝集陰性であった。また病原性も確認し得なかつたことからこれらは二次感染菌と推察された。 In the period 1977-1979, 7 epizootics occurred among the pen-cultured coho salmon Oncorhynchus in the Tohoku district and Hokkaido, Japan. Thirty-eight vibrio strains were isolated from the diseased fish as causative organisms. The isolates were studied taxonomically and serologically. The results obtained were summarized as follows: 1) Of the 38, 33 strains (No. 1-No.33) were identified as V. anguillarum, and they all showed positive agglutination with rabbit antiserum against V. anguillarum type J-O-3. 2) The pathogenicity of a representative strain (No. 1) of those 33 strains (No. 1-No. 33) was demonstrated by immersion method (ca. 10^5 cells/ml, 10min.) using chum salmon O. Keta fingerlings. 3) Five strains (No. 34-No. 38) of vibrio isolates at Abuta, Hokkaido were found to be different from V. anguillarum on the basis of taxonomy and serology. Also, the representative strain (No. 37) of those failed pathogenicity against rainbow trout Salmo gairdneri and coho salmon fry. On the basis of the above results, those five organisms were assumed to be secondarily infected organisms.