Toltrazuril (Baycox®) treatment against coccidiosis caused by Eimeria sp. in Japanese quails (Coturnix coturnix japonica)

Coccidiosis is the most predominant parasitic disease affecting Japanese quails (Coturnix coturnix japonica) in commercial farms. Coccidiosis as a subclinical infection is difficult to diagnose without parasitological examinations. Oocysts of two Eimeria species, E. bateri and E. tsunodai, were determined in the analysed quail flock. Infected birds were administered Baycox 2.5% at the dose of: group I - 7 mg toltrazuril/kg BW per day provided in drinking water (1.5 ml/0.5 l H2O) that was available 24 h for 2 days, group II - 14 mg/kg BW (3 ml/0.5 l H2O), and group III - 24.5 mg/kg BW (5 ml/0.5 l H2O); in groups II and III, the solutions were available 8 h/24 h for 2 days. After the first day of the treatment, the number of excreted oocysts (OPG - oocysts per gram) increased, a steady decrease in oocyst counts began on the second day of Baycox administration and lasted until a three-day period when no oocyst were determined in faecal samples. Regardless of the dose applied, toltrazuril (Baycox) completely eliminated E. bateri coccidia and led to a highly significant reduction in the number of E. tsunodai oocysts. The results suggest that the effectiveness of toltrazuril varies depending on coccidia species and developmental stages of the parasite. From the clinical point of view, the treatment applied significantly reduces the number of coccidia oocysts in commercial flocks of Japanese quails.