Studies on the Classification and Pathogenicity of Ectoparasitic Protozoa of Cultured Marine Fishes in Japan

1995 Fiscal Year Final Research Report Summary

• Project/Area Number: 05660356
• Research Category: Grant-in-Aid for General Scientific Research (C)
• Allocation Type: Single-year Grants
• Research Field: Basic veterinary science/Basic zootechnical science
• Research Institution: Nippon Veterinary and Animal Science University
• Principal Investigator: IMAI Soichi Nippon Veterinary and Animal Science Uniersity, Department of Veterinary Parasitology, Professor, 獣医畜産学部, 教授 (90120758)
• Project Period (FY): 1993 – 1995
• Keywords: classification / ultures fish / ectoparasite / fish diseasec / parasitic ciliates / Scyphidia / Trichodina

Research Abstract

Ectoparasitic ciliate protozoa of two cultured marine fishes, tiger puffer and yellow tail, in Japan were surveyed and examined for is pathogenicity to the host. From the examination by light and scanning electron microscopy, one species of the genus Trichodina was found from the tiger puffer, which is dome-like in body shape, having adhesive disc of 39-54 mum in diameter with 29-35 denticles. Since this species has different morphological characters from those of known 3 species described from puffers, it was concluded to be a new species. In yellow tail, two trichodined species and one species of the genus Scyphidia were detected. Of them, one trichodina was identified as T.jadranica which has been reported from relatively wide range of hosts, and one as a new species. From the results, it was suggested that the cultures marine fishes in Japan have respective peculiar trichodinid species. In the histopathological examination of the host gill, Trichodina sp.from the tiger puffer and Scyphidia sp.from the yellow tail were assumed to have fairly heavy pathogenicity to their host.