Revista Colombiana de Ciencias Pecuarias
versão impressa ISSN 0120-0690
ERRECALDE, Carlos A; PRIETO, Guillermo F; LUDERS, Carlos F e GARCIA OVANDO, Hugo. Pharmacokinetics and bioavailability of ceftiofur sodium in goats. Rev Colom Cienc Pecua [online]. 2006, vol.19, n.3, pp. 306-311. ISSN 0120-0690.
Pharmacokinetic parameters of ceftiofur sodium were determined with a unique dose of 2.2 mg/kg either by the intravenous on the intramuscular routes, in a crossed design treatment in non pregnant adult female goats (n= 6). Variations in plasmatic concentrations over time were determined by the microbiological assay in Mueller-Hinton agar, with Providencia alcalifaciens as indicator. The limit of quantification was set in 0.039 mg/ml. The plasmatic concentrations of Ceftiofur were determined by the non compartimental pharmacokinetic model using sofware PK Solution 2.0. The parameters obtained when the intravenous route was used were: average elimination time (t1/2 b) = 1.63 ± 0.04 hours, total clearance (Cltot) = 3.3 ± 1.1 ml/kg/min, volume of distribution (Vdss) = 0.38 ± 0.19 L/Kg, area under the curve (ABC) = 716.5 ± 225.5 mg/min/ml. These values did not differ significantly from those obtained by the intramuscular test (P < 0.05) and are similar to those informed in other animal species for the same drug. When the intramuscular route was used , the maximum concentration (Cmáx) of 3.6 ± 0.5 mg/ml was obtained at a maximum time (tmáx) of 0.53 ± 0.31 min, and the bioavailability was high (97.6 ± 0.1%). The results indicate that the intramuscular application provides fast absorption and optimal bioavailability, generating plasmatic levels that exceed the MIC90 for sensitive respiratory pathogens for a period of 12 hours. Considering these results and a MIC (£0.06 mg/ml) for bacteria like Pasteurella haemolitica and multocida, the treatment of this type of infections in goats, requires 1.3 mg/Kg every 12 hours by intramuscular route, to obtain a predictive effectiveness (t> MIC) of 77.8%.
Palavras-chave : ceftiofur; cephalosporins; goats; Pasteurella spp; pharmacokinetics.