マガキ幼生の細菌性壊死症に対する抗菌剤の治療効果

• Main Authors: Matsubara, Danji, Tanaka, Makoto, Soumyou, Yoshie, Hirakawa, Kohji, Doi, Ryuji, Nakai, Toshihiro
• Format: Article in Journal/Newspaper
• Language: Japanese
• Published: 日本魚病学会 2014
• Subjects: Crassostrea gigas; chemotherapy; bacillary necrosis; Vibrio splendidus; Pacific oyster; 660; Pacific
• Online Access: http://ir.lib.hiroshima-u.ac.jp/00025899; http://ir.lib.hiroshima-u.ac.jp/files/public/2/25899/2014101615285289853/FishPathol_37_183.pdf

三倍体マガキ幼生の細菌性壊死症に有効な薬剤の検索を目的として、人為感染および自然感染に対する8種抗菌剤の治療効果を調べた。Vibrio属細菌4種7株を用いた人為感染に対しては、クロラムフェニコールの効果が最も高く、エリスロマイシン, ノボビオシン, ストレプトマイシンなどにも顕著な治療効果が認められた。自然感染に対しては、幼生を高密度飼育した場合クロラムフェニコール添加区の死亡率が最も低かったが、低密度飼育では上記4種薬剤は同程度の防除効果を示した。 Eight antimicrobial compounds were examined to evaluate their therapeutic effects against experimentally or naturally induced vibriosis of the Pacific oyster Crassostrea gigas. In experimental infections with a strain of Vibrio splendidus biovar II, a causative agent of bacillary necrosis of cultured triploid oyster larvae, chloramphenicol (CP) exhibited complete protection against challenges at 10^5 or 10^6 CFU/mL, and erythromycin (EM), novobiocin (NB), gentamicin and streptomycin (SM) were effective to reduce the mortality, but nalidixic acid or oxytetracycline was not. CP and EM were also highly effective against experimental infections with other six strains of Vibrio species (V. splendidus biovar II, V. pelagius I, V. campbellii, and V. tubiashii) which had been isolated from oyster larvae or the rearing water, but NB and SM were less effective. On the other hand, not only CP and EM but also NB and SM exhibited higher protection against the natural infection.