Yasunobu, H., Nagayama, H., Nakamura, K., Hatai, K.-1997
Nippon Suisan Gakkaishi, 63(1): 56-63
Abstract:
Halocrusticida (= Atkinsiella) okinawaensis was isolated from diseased swimming crab larvae Portunus trituberculatus 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 3.25 mas remarkably reduced.
Experimental infections using zoea I demonstrated that the infection with H. okinawaensis was controlled by keeping the pH of rearing water at 9.25. Acute toxicities of pH 9.25 to swimming crab zoea, rotifer Brachionus plicatilis rotundiformis, brine shrimp Artemia salina, and unicellular alga Nannochloropsis sp. were not observed. Survival rates of swimming crab larvae from zoea I to juvenile crab I in the center mere apparently raised by applying this pH adjustment at 9.25.
(Hyogo Prefectural Fisheries Expt. Stn., Akashi Hyogo 674 Japan)
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