飼育水のpH調整によるガザミ幼生真菌症の防除 Prevention of a Fungal Infection in the Swimming Crab Portunus trituberculatus Larvae by High pH of Rearing Water
<i>Halocrusticida (=Atkinsiella) okinawaensis</i> was isolated from diseased swimming crab larvae <i>Portunus trituberculatus</i> in the Hyogo Prefectural Mariculture Center, and pathogenicity of the isolates was confirmed by infection experiments with zoeal larvae of the crab. The isolates grew in PYGS broth at pH 5-9, but the growth at pH 9.25 was remarkably reduced.<br>Experimental infections using zoea-I demonstrated that the infection with <i>H. okinawaensis</i> was controlled by keeping the pH of reaing water at 9.25. Acute toxicities of pH 9.25 to swimming crab zoea, rotifer <i>Brachionus plicatilis rotundiformis</i>, brine shrimp <i>Artemia salina</i>, and unicellular alga <i>Nannochloropsis</i> sp. were not observed. Survival rates of swimming crab larvae from zoea-I to juvenile crab-I in the center were apparently raised by applying this pH adjustment at 9.25.
日本水産学会誌 63(1), 56-63, 1997-01-15