Intramuscular and oral single-dose pharmacokinetic profiles and multi-tissue distribution of thiamphenicol in Chinese soft-shelled turtle (Trionyx sinensis)

The aim of this investigation was to reveal the pattern of disposal process of thiamphenicol (TAP) in Chinese soft-shelled turtle after oral (PO) and intramuscular (IM) administration routes. TAP concentration levels in Chinese soft-shelled turtle plasma and multi-tissues were measured by HPLC-MS/MS. Pharmacokinetic (PK) parameters of TAP were estimated using WinNolin software based on the non-compartmental analysis. Compared with IM route, higher absorption, longer elimination time and greater AUC0-∞ value for TAP in plasma were observed after PO treatment. It indicated that Chinese soft-shelled turtle has a higher bioavailability for TAP following PO administration than IM medication. For tissue distribution, higher TAP concentrations were also found following PO medication than IM administration. The prescribed medication dosage of TAP (17.5 mg/kg bw) against susceptible strains with MIC should be below 0.22 mg/L (PO) and 0.13 mg/L (IM) based on the values of Cmax/MIC >10 and AUC0–24 h/MIC >125. TAP elimination pattern was investigated, and skirt was suggested as residual target tissue. Withdrawal time (WT) of TAP was calculated using WT 1.4 software, and the recommended WT was 17 d (391 ℃-day). The present investigation can serve as reference data for TAP use in Chinese soft-shelled turtle.