Bioequivalence Of Tulathromycin Injection In Pigs

Tulathromycin is a vaternary macrocyclic antibiotic,which has a lot of advantages of strong antibacterial activity,broad spectrum,rapid absorption rate,high bioavailability,a single administration is enough for a full-course therapy,long elimination half-life and lasting effects.In veterinary clinic,Tulathromycin is mainly used in the prevention and treatment of respiratory diseases on pigs and cows.In this study,the pharmacokinetic study of terrapamycin injection in pigs was carried out.At the same time,the study also evaluates whether the pharmacokinetic characteristics of these two injections in pigs is bioequivalent objectively and scientificallyThe pharmacokinetics of Tulathromycin in pigs:60 cross-bred healthy,non-lactating pigs,were used.These pigs are banned to eat anything except water before 16 hours of the experiment.The pigs were randomly divided into two groups,each group has 30 pigs.The first groups was administered with Tulathromycin?Draxxin?injection by intramuscular,at a single dose of 2.5 mg·kg^-1 body weight;whereas the second group was administered with Tulathromycin?Shandong Lukang?injection by intramuscular,at the same dose.Tulathromycin was extracted by the acetonitrile.and the Tulathromycin concentrations were determined by high performance liquid chromatography with Tandem mass spectrometry.A non-compartmental analysis of drug plasma concentration vs.time profiles was performed with pharmacokinetic modeling using Winnonlin software.Following the injection of Tulathromycin?Draxxin?,the main pharmacokinetic parameters were as follows:Tmax,0.172±0.082 h;Cmax,892.027±313.749 ng/mL;t1/2?,86.802±45.655 h;CL,381.807±147.919mL/h/kg;AUC0-t,7026.587±2925.522h·ng/mL;AUC0-?,7564.122±2902.318 h·ng/mL.Following the injection of Tulathromycin?Shandong Lukang?,the main pharmacokinetic parameters were as follows:Tmax,0.208±0.235 h;Cmax,792.853±340.81 ng/mL;t1/2?,67.914±38.252 h;CL,363.774±152.98 mL/h/kg;AUC0-t,7466.137±3054.329 h·ng/mL;AUC0-??8043.4±3140.398 h·ng/mL.The result shows that the pharmacokinetic characteristics of these two injections in pigs is bioequivalent.