Efficacy of Oral Administration of Praziquantel and Mebendazole against Microcotyle sebastis (Monogenea) Infestation of Cultured Rockfish (Sebastes schlegeli).

Abstract

The efficacy of praziquantel and mebendazole against Microcotyle sebastis infestation in juvenile rockfish by oral administration was evaluated at low (10 ± 1°C) and high (20 ± 1°C) water temperatures. Oral administration of praziquantel or mebendazole resulted in significant reduction or complete extermination of M. sebastis infestation in juvenile rockfish. The treatment efficacy of praziquantel 200 mg/kg B. W. at both temperatures (10°C and 20°C) and mebendazole 200 mg/kg B. W. at 20°C was 100%. Praziquantel was more effective against M. sebastis than mebendazole at 10°C. Our results strongly suggest that oral administration of praziquantel and mebendazole can be used practically in netpen-culture of rockfish as an effective control measure against M.sebastis infestations without imposing handling-related stress to fish.