| In this experiment, the water temperature was raised at (26±2)℃. The experiment used high performance liquid chromatography tandem mass spectrometry(HPLC-MS/MS) to study thiamphenicol in pharmacokinetics of carp with 30 mg/(kg·bw) single dose of carp feed. Data were analyzed using DAS 2 dynamics software, and the experimental results suggest a two-compartment model of primary absorption. The peak of thiamphenicol (TAP) in muscles, kidneys, liver, skin, gills, spleen, and plasma were 16, 2, 16, 8, 0, 2, 16 h; the Cmax were 15.6, 35.3, 12.4, 9.0, 33.0, 11.6 mg/kg, and 21.0 mg/L; the area under curve (AUC) was 1084.5, 1578.1, 777.3, 541.1, 0.1, 478.1 mg/(kg·h), and 485.1 mg/(L·h); the t1/2β was 11.4, 100.2, 54.2, 41.1, 69.5, 38.0, and 71.9 h. The results showed that the distribution and elimination rate of TAP in carp tissues varied greatly; the peak time of renal drugs is shorter; the peak concentration is higher than in other tissues, and the elimination half-life is higher than that in other tissues, which suggested that kidneys are the main organ of TAP accumulation and metabolism. In accordance with the Ministry of Agriculture, Animal Food in Veterinary Drugs Maximum Residue Limit document provides that the maximum of TAP in aquatic animal residue limit (MRL) shall not be higher than 50 μg/kg. In this experiment, the amounts of TAP residues in muscle, kidney, liver, skin, spleen, and plasma were lower than MRL, starting from 16, 16, 12, 12, 12, 10, and 12 d respectively. It is recommended that the period of withdrawal should be no less than 16 d. |
