Effects of essential oils combination on sporulation of turkey (Meleagris gallopavo) Eimeria oocysts

Avian coccidiosis is the most important parasitic disease in poultry production, which inflicts numerous losses to the industry. The extensive use of anticoccidial drugs leads to parasite resistance and drug residue in poultry products. In the present study, we aimed to investigate the effects of three famous essential oils (EOs) and their combination on inactivation of mixed oocysts of Eimeria adenoides, Eimeria dispersa, Eimeria meleagrimitis, and Eimeria meleagridis. The EOs of Thymus vulgaris, Artemisia sieberi, and Mentha pulegium were prepared.  After inoculation of each turkey with 7×105 sporulated oocysts, fresh unsporulated oocysts were harvested from their feces. To evaluate the sporulation inhibition effect, 5×104 oocysts were used in each treatment. Each EO was used in increasing concentrations. Half maximal inhibitory concentration (IC50) was determined for each EO and they were blended in pairs based on IC50 line. Our results showed that the IC50 values for mentha, artemisia, and thyme were 22.92, 40.5, and 53.42 mg/ml, respectively. According to our results, artemisia and thyme combination has a synergistic effect, whereas the combination of a high concentration of mentha with a low concentration of thyme had an antagonistic effect. During this study, no interactions were observed between mentha and artemisia.