Antiparasitic effects of Sophora flavescens root extracts on the ciliate, Cryptocaryon irritans

作者：Goto Tsuyoshi^*; Hirazawa Noritaka; Takaishi Yoshihisa; Kashiwada Yoshiki

来源：Aquaculture, 2015, 435: 173-177.

DOI：10.1016/j.aquaculture.2014.09.007

• Antiparasitic effect
• Cryptocaryon irritans
• Herb
• Pagrus major
• Sophora flavescens

The antiparasitic effects of 59 water- and methanol-soluble herbal extracts were screened for their potential to inhibit cilia-based motility of the protozoan, Cryptocaryon irritans, during its infective (theront) phase. Both the water-and methanol-soluble extracts of five herbs had strong antiparasitic activity. In vitro results were confirmed in vivo in oral-challenge trials with the red sea bream, Pagrus major. The water-soluble Sophora flavescens extract had the most potent anti-C. irritans activity. For a short-term oral-challenge trial, the number of parasites in the groups treated with 5 or 10 g.kg(-1) feed of S. flavescens water-soluble extract was significantly lower than that in the control group and the group treated with 10 g.kg(-1) feed reduced the number of parasites by more than 40% compared with the control. In an 80 day oral challenge trial with P. major, all the fish in the group that were treated with the extract (5 g.kg(-1) feed) survived throughout the experimental period, which contrasts with the 100% mortality seen in the control group. Furthermore, the anti-C. irritans effect of the extract in previously infected P. major was also evaluated in a 4 day oral-challenge trial. In this trial, the number of parasites in the group treated with the extract (5 g.kg(-1) feed) was reduced by 30% compared with the control group. These results suggest that the water-soluble S. flavescens extract could be effective for controlling C. irritans infections.

• 出版日期2015-1-1