Insecticidal Activity of Some Traditionally Used Ethiopian Medicinal Plants against Sheep KedMelophagus ovinus

Twelve medicinal plants and a commercially used drug Ivermectin were examined for insecticidal activity againstMelophagus ovinussheep ked at different time intervals usingin vitroadult immersion test. The findings show that at 3.13 µL/mL, 6.25 µL/mL and 12.5 µL/mL concentration ofCymbopogon citratus,Foeniculum vulgareandEucalyptus globulusessential oils respectively, recorded 100% mortalities againstM. ovinuswithin 3 hour of exposure. Significantly higher insecticidal activity of essential oils was recorded (P=0.00) when compared to 10 μg/mL Ivermectin after 3-hour exposure ofM. ovinusat a concentration of ≥1.57 μL/mL, ≥3 μL/mL, and ≥12.7 μL/mL essential oils ofC. citratus,F. vulgare, andE. globulus, respectively. Among essential oils,C. citratushas showed superior potency at a three-hour exposure of the parasite (P=0.00) at a concentration of ≥0.78 μL/mL. Strong antiparasitic activity was recorded by aqueous extract ofCalpurnia aurea(80% mortality) at a concentration of 200 mg/mL within 24 h among aqueous extracts of 9 medicinal plants. The results indicated all the four medicinal plants, particularly those tested essential oils, can be considered as potential candidates for biocontrol ofM. ovinussheep ked.