[The bioequivalence of intramuscular and subcutaneous administration of a formulation of oxytetracycline in the young bull].

A bioequivalence study was performed in 6 bullocks to compare intramuscular (im) and subcutaneous (sc) routes for repeated treatments with an oxytetracycline formulation. Basic pharmacokinetic parameters were determined after a 10 mg/kg intravenous administration. Bioavailabilities for both im et sc routes were close to 85%. The pharmacokinetic parameters were used to perform an analysis of variance, and to determine the 95% confidence intervals and Westlake symmetrical confidence intervals. The two routes were significantly different regarding maximum concentration. The following symmetrical confidence intervals were calculated: area under the curve (+/- 20%), minimum concentration (+/- 51.5%), period during which plasma concentration was above 1 microgram/ml (+/- 25%). The two routes were bioequivalent for the area under curve.