The Pharmacokinetics Of Enrofloxacin In Chinemys Reevesiis

The pharmacokinetics of enrofloxacin in Chinemys reevesiis following intramascular injection and oral administration was determined by HPLC-MS/MS.Enrofloxacin is the third generation of quinolones and the first animal-specific drugs.Now,it is also the commonly used drugs for reptiles.Chinemys reevesiis is a common native turtles in China,not only be used as medicine or food,but also for viewing.It is in addition to be another economic turtle species except Trionyx sinensis.With the scale of farming has expanded each year,disease problems have gradually highlighted,but the technical problems encountered in clinical medicine has become the bottleneck of industrial development.At present,enrofloxacin is often used in the treatment of diseases of Chinemys reevesiis,such as respiratory diseases and urinary system diseases.However there is few reports about pharmacokinetic of enrofloxacin in Chinemys reevesiis,this experiment filled the gap.In this experiment,20 healthy chinese pond turtles(800±50g)were selected from a farm in Wuxi,Jiangsu Province.All trules were female.After holding for two weeks,they were selected and followed by a single dose of enrofloxacin(10mg/kg)by intramascular injection and forced oral administration(gastric intubation)respectively.Blood samples were collected continuously for the same subject 13 times from the jugular sinus.Samples were obtained and assayed by HPLC-MS/MS,and the corresponding pharmacokinetic parameters were calculated with non-compartmental models by Kinetic4.4.The main pharmacokinetic parameters of forced oral administration were Cmax:7.49?g/ml,Tmax:12h,T1/2?z:99.85 h and AUC0-?: 531.67 h*?g/m L;The main pharmacokinetic parameters of intramuscular injection were Cmax:5.85?g/ml,Tmax:4h,T1/2?z: 30.42 h and AUC0-?:193.6 h*?g/m L.The results showed that enrofloxacin was absorbed faster by intramuscular injection,but was absorbed better and comprehensived by forced oral administration in Chinemys reevesiis.And the retention time of forced oral administration was longer.So in the control of Chinese turtle disease,enrofloxacin is more suitable for oral administration.At different concentrations,the pharmacokinetic characteristics of enrofloxacin in Chinese pond turtle were also different.Twenty healthy Chinese pond turtles were randomly divided into two groups.After holding for two weeks,they were selected and followed by a single dose of enrofloxacin by intramascular injection at different concentrations:10mg/kg and 20mg/kg.Samples were obtained and assayed by HPLC-MS/MS,and the corresponding pharmacokinetic parameters were calculated with non-compartmental models by Kinetic4.4.The main pharmacokinetic parameters of 10mg/kg were Cmax:5.85?g/ml,Tmax:4h,T1/2?z:30.42 h and AUC0-?:193.6 h*?g/mL.The main pharmacokinetic parameters of 20mg/kg were Cmax:11.3?g/ml,Tmax:8h,T1/2?z:47.04 h,AUC0-?:597.46 h*?g/mL.At the two administrations,the peak time in the high concentration group was twice as high as that in the low concentration group,and the Cmax and AUC of it were significantly higher than those in the low concentration group.The plasma concentration in the high concentration group was 0.31?g/mL at 196 h,which was significantly lower than that in the low concentration group(0.06±0.03)?g/mL.It can be seen that different concentrations of enrofloxacin in chinese pond turtle pharmacokinetics characteristics had some differences.The group of 20mg/kg absorbde comprehensivly and relative bioavailability,but the required absorption time and metabolic time are longer than the group of 10 mg/kg.At the same time,this study explored the pharmacokinetic characteristics of ciprofloxacin,a metabolite of enrofloxacin in chinese pond turtle.The results showed that enrofloxacin in the Chinese grass turtle would be metabolized into ciprofloxacin,but the conversion rate was far lower than livestock and poultry,antibacterial effect is mainly dependent on the original drug enrofloxacin.In summary,the different concentration and administration of drugs of enrofloxacin will affect the pharmacokinetics of it in the chinese pond turtle.When we need to quickly achieve the effect,intramuscular injection of enrofloxacin will be better.When we need to continue to administer and the turtle metabolic state is normal,it is recommended that forced oral administration of enrofloxacin by gastric intubation.10mg/kg and 20mg/kg administration concentration in the Chinese pond turtle were both widely distributed and had good absorption,but considering the drug residue,it is recommended to choose 10mg/kg for the dose,and once a day.