Comparison of effect of nicotine and levamisole and ivermectin on mortality of leech

ObjectiveTo study the effect of different doses of nicotine on Limnatis in comparison with levamisole and ivermectin.MethodsIn this interventional experimental study in July 2012, the amount of 61 mature leeches of Limnatis nilotica species were collected and anti-parasitic effects of drug treatments using anti-leech method were assessed. So that, a leech was placed in the dishes with 600 mL spring water and leech's paralysis and death time were recorded accurately for 720 min. A total of 9 replicates were considered for each treatment. Six drug treatments were considered. Pharmacological treatments include nicotine (5, 10 and 20 mg doses), levamisole (10 mg), ivermectin (10 mg) and distilled water. Data were analyzed using the Sigma ASA 2 software and pair t-test method with less than 0.05 confidence levels.ResultsThe results of present study show that doses of 5, 10 and 20 mg of nicotine, with time average of 2.44±0.52, 1.88±0.78 and 1.55±0.72 min cause to death of leeches. Ivermectin and levamisole cause to death of leeches, averaging 7.44±1.12 and 14.66±5.09 min, respectively. Distilled water treatment has been reported as an ineffective group. Data analysis showed that the group receiving 5 mg nicotine, had minimum time of death and there are statistical differences among all groups (P>0.05), but there are not significant differences between treatments receiving 10 mg nicotine, with 5 and 20 mg nicotine treatments.ConclusionsIt appears that nicotine compound as the effective substance of tobacco plant has the strong anti-leech effect on Limnatis nilotica species and can be used as leech purposes in the future.