Antiparasitic effects of Lawsonia inermis, Satureja khuzestanica and Citrullus colocynthis on fish parasite: Ichthyophthirius multifiliis

In this study the antiparasatic effect of three herbal extract Lawsonia inermis, Satureja khuzestanica and Citrullus colocynthis on  Ichthyophthirius multifiliis were investigated. Firstly, the hydro alcoholic extract of plants was prepared according to maceration method. Then theront and tomont stages of parasite isolated from heavily infected rainbow trout and were exposed to serial increasing two-fold dilution of each extract. Immobilized (dead) parasites were recorded every 4 hours for 12 hours in each dilution and 12 h LD50 of each extract calculated using probite method. Malachite green used as positive control. Results showed that 12h LD50 of L. inermis, S. khuzestanica and C. colocynthis and Malachite on parasite tomont were 4.68, 2.32, 5.21 and 0.24 mg/l respectively; meanwhile 12 h LD50 of mentioned extract on theront were 0.57, 0.45, 2.37 and 0.121 respectively. According to results it can be concluded that Although L. inermis, and S. khuzestanica showed mild anti parasitic effects against Ichthyophthirious; these effect was insignificant compare to therapeutics such as malachite green. These extracts can be used as a complementary treatment along with chemical treatment.