Pharmacokinetic Characteristics of Diclazuril in Japanese Quails (Coturnix japonica) and Domestic Pigeons (Columba livia).

Coccidiosis, caused by the protozoan Eimeria, is a significant disease in poultry farms worldwide, leading to substantial economic losses. Triazines, benzene-aceto-nitrile derivatives, are widely employed in the field of veterinary healthcare to combat the hazardous impacts of protozoan parasite infestation comprising coccidiosis. The current research was designed to investigate the pharmacokinetic profile of diclazuril, a member of triazines, in Japanese quails (Coturnix japonica) and domestic pigeons (Columba livia) following single oral administration at 0.3 mg/kg body weight. 78 Quails (male: female, 1:1, 7 weeks old) and 78 pigeons (male: female, 1:1, 4 weeks old) were randomly divided into 13 groups for each species (n=6 birds/group). Plasma samples were obtained at various time intervals (at time 0 [preceding diclazuril administration], and 0.5, 1, 4, 8, 12, 24, 48, 72, 96, 120, 144, and 168 hours after diclazuril administration) to determine its concentration utilizing high-performance liquid chromatography (HPLC). The noncompartmental approach was applied to assess the pharmacokinetic parameters via the aid of WinNonlin 8.3 software. In quails and pigeons, the peak plasma concentrations were 5.35 and 9.14 µg/mL attained at 8 hours, respectively. Additionally, the elimination half-lives (T_1/2-z) were 30.74 and 26.48 hours, and the area under the plasma concentration-time curve from time zero to the last sample (AUC_0-last) values were 155.67 and 343.57 µg h/mL, respectively. The mean residence time was 30.71 hours in quails and 39.68 hours in pigeons. Diclazuril exhibited favorable pharmacokinetic characteristics after oral administration at a dose of 0.3 mg/kg in quails and pigeons. However, to adjust the dosage regimen for curing coccidiosis, a future study is warranted to determine the clinical efficacy against coccidia infection. Moreover, further investigation is needed to evaluate the tissue residues and calculate the withdrawal time of diclazuril in quails and pigeons. [ABSTRACT FROM AUTHOR]