The residues and pharmacokinetics of florphenicol in Trionyx sinensis following intramascular injection and oral administration

To study the residues and pharmacokinetics of florphenicol in Trionyx sinensis with different treatments, one hundred and sixty healthy T. sinensis were selected and followed by a single dose of florphenicol (30 mg·kg_-1) with intramascular injection and oral administration respectively. Serial serum samples were obtained and assayed by reversed-phase HPLC, and the corresponding pharmacokinetic parameters were calculated with 3p87. A one-compartment open model best fits the data. The major pharmacokinetic parameters were as follows: AUC=76.45 mg·L^-1·h^-1, T_1/2ka=1.31 h, T_1/2ke=4.48 h, and C_max=7.09 mg·L^-1 in intramascular injection group; while AUC =109.42 mg·L^-1·h^-1, T^1/2ka=1.73 h, T_1/2ke=3.63 h, and C_max=10.64 mg·L^-1 in oral administration one. It suggested that the assimilation of florphenicol was faster, the level of risidue concentration was higher, the maintain time was longer, and the bioavailability was higher in oral administration group as compared to intramascular injection. Florphenicol residue eliminated slowly in musculature.