Antiparasitic effect of dietary Romet registered 30 (SDMX-OMP) against ciliate Cryptocaryon irritans infection in the red sea bream Pagrus major and tiger puffer Takifugu rubripes

• Published in: Aquaculture 2012-05, Vol.344-349, p.35-39
• Main Authors: Kawano, Fumi, Hirazawa, Noritaka, Gravningen, Kjersti, Berntsen, Jan Oppen
• Format: Article
• Language: English
• Subjects: Cryptocaryon irritans; Marine; Pagrus major; Takifugu rubripes
• ISSN: 0044-8486
• DOI: 10.1016/j.aquaculture.2012.02.028

We investigated the effects of dietary Romet registered 30 (sulfadimethoxine-ormetoprim (SDMX-OMP)) on Cryptocaryon irritans infection in red sea bream Pagrus major and tiger puffer Takifugu rubripes. In Experiment I, 100% mortality of P. major due to C. irritans infection was observed at 10days and 21days after exposure to theronts (infective stage) in the a control group without Romet registered 30 and the group treated with 50mg Romet registered 30/kg body weight (BW)/day for 14days, respectively. Thus, mortality in the treated group was markedly delayed compared with that in the control group. In Experiment II, 100% mortality of P. major in the control group due to C. irritans infection was recorded at 11days after exposure to theronts. In contrast, mortality due to parasite infection was not observed in the group treated with Romet registered 30 at 50mg/kg BW/day for 14days, and no parasites were found in any surviving fish after 33days exposure. In addition, the number of parasites on the gills of T. rubripes treated with 50mg Romet registered 30/kg BW/day for 14days was significantly lower than that in the control group after 16days exposure. These results show that in-feed Romet registered 30 at 50mg/kg BW/day for 14days had antiparasitic and therapeutic effects against C. irritans in both P. major and T. rubripes. Thus, dietary Romet registered 30 could be useful for controlling C. irritans infection.