Disposition of oxytetracycline in pigs after i.m. administration of two long‐acting formulations

Abstract

Two commercially available long-acting oxytetracycline (OTC) formulations were administered by the intramuscular (i.m.) route to six healthy pigs at the recommended dose of 30 mg/kg. After 2 h the mean maximum concentration (C(max)) reached values of 8.1 +/- 2.2 and 15.4 +/- 11.1 microg/mL, respectively. These concentrations remained higher than 0.5 microg/mL for more than 5 days after drug administration. The area under the concentration time curve (AUC09 days) of each formulation was 255 +/- 76.5 and 399.2 +/- 123 microg. h/mL, respectively, and the mean residence time (MRT) was around 3 days for both formulations. No significant differences were observed between the pharmacokinetic parameters of the two formulations, showing the bioequivalence of the two formulations studied according to the criteria established by the Food and Drug Administration (FDA) and the Committee for Veterinary Medicinal Products (CVMP).

Disposition of a long‐acting oxytetracycline formulation in Thai swamp buffaloes (Bubalus bubalis)

“…The doses used in this study were selected on the basis of an earlier study on claves and pigs administered i.m. (Bush et al ., ; el Korchi et al ., ). The total volume of drug did not exceed 25–30 mL at any one site.…”

“…This absorption profile could be triggered by the drug being released slowly from the injection site to the blood. These results also agree with the previous studies in pigs where a slowdown in absorption has been shown after OTC‐LA treatment (de Banting & Baggot, ; el Korchi et al ., ). The AUC last values increased in dose‐dependent manner.…”

“…Indeed, the average AUC last value of the 20 mg/kg treatment group was 662.17 ± 145.97 h·μg/mL, while a value of 800.29 ± 70.08 h·μg/mL was found in the 30 mg/kg treatment group. The t max value obtained in this study was quite longer than those reported in calves (8.0 h; Kumar & Malik, ), pigs (1.7–2.7 h; el Korchi et al ., ), and goats (2–4 h; Rule et al ., ) undergoing i.m. OTC‐LA treatment.…”

Pre-study and in-study validation of an ultra-high pressure LC method coupled to tandem mass spectrometry for off-line determination of oxytetracycline in nasal secretions of healthy pigs

“…1) is a broad-spectrum antibacteriostatic widely used in the veterinary treatment of respiratory and gastro-intestinal infectious diseases in pigs and several other species [1][2][3][4][5]. The formulations used are injectable, oral solution and feed medication.…”

“…Several pharmacokinetic studies of OTC in pig plasma have been published [1][2][3][4][5]. However, the successful of an antimicrobial therapy requires the knowledge of local concentrations at the site of infection.…”