. Évaluation in vivo en station de l’activité acaricide de l’huile essentielle de Ocimum gratissimum sur une infestation contrôlée de bovins Borgou par la tique exotique Rhipicephalus microplus au Bénin

Abstract

The acaricidal activity of the essential oil of Ocimum gratissimum on the tick Rhipicephalus microplus was evaluated on Borgou cattle in Benin. The cattle were infested three times (D- 18; D-11 and D-4) with R. microplus larvae aged between 14 to 21 days. Three of the five infested animals were sprayed with 5% O. gratissimum essential oil solution four days after the last infestation. Two control animals were treated with same solution but lacking the essential oil. Fallen ticks were collected each morning for four consecutive weeks. The effect of O. gratissimum essential oil on different developmental stages and egg-laying rates of Rh. microplus was determined. Results show a decreased tick infestation rate (4.43%) in treated cattle compared to the controls (15.11%). Males were more infested than females and the infestation gradually declined after each week of treatment