Effect of three anthelmentics on disposition kinetics of florfenicol in goats.

The pharmacokinetic aspects of florfenicol (FLO) were investigated via intravenous (I.V.) and intramuscular (I.M.) injections in five goats at a dose of 20 mg kg(-1) b.wt. Animals were pre-treated with albendazole orally in a dose of 2.5 mg kg(-1) b.wt, ivermectin or rafoxanide subcutaneously in a dose 0.2 and 7.5 mg kg(-1) b.wt, respectively. Florfenicol was injected intramuscularly two hours following anthelmentic administration and blood samples were taken by jugular venapuncture at standardized intervals. The concentrations of florfenicol (FLO) in serum were determined by high performance liquid chromatography (HPLC) method. The obtained results revealed that ivermectin administration did not induce a significant difference in serum florfenicol concentration between anthelmentic-treated and non-treated goats. On the other hand, goats pre-treated with rafoxanide or albendazole showed a significant decrease in serum florfenicol level as compared to non-anthementic treated goats. The absorption half-life (t(½ab)), C(max), AUMC, AUC and systemic bioavailability (F%) are significantly decreased, whereas elimination half-life (t(½el)) and MRT are increased in goats pre-treated by the three tested anthementics.