Pharmacokinetics of tilmicosin in calves after single subcutaneous application

D. Dimitrova, P. Petkov, D. Tsoneva

Abstract. The aim of this investigation was determination of main pharmacokinetic parameters of tilmicosin after single subcutaneous application of Tilmovet solutio pro imjectionibus 30 % (Biovet LTD Peshtera). Tilmovet solutio pro imjectionibus 30 % was applied subcutaneously, as a 10 mg/kg dose, to 8 (4 male and 4 female, Brown Bulgarian breed) clinically healthy calves, aged 1.5 – months, weighing 71.5 to 91 kg. Blood plasma tilmicosin concentrations were assayed by HPLC. The main pharmacokinetic parameters were calculated. Pharmacokinetic parameters (mean ± SEM) of tilmicosin were as followed: t – 1/2β 32.33 ± 0.99 h, C – 0.976 ± 0.06 μg/mL, T – 1.00 ± 0.00 h, AUC h–18.22 ± 1.23 g.h/mL. Plasma tilmicosin concentrations higher than 0.1 ±0.009 max max 0→72 μg/mL were detected over the entire 72-hour period of observation after the s.c. application.