Studies On Efficacy And Pharmacokinetics Of Anticoccidial Drug Adprin

Chicken coccidiosis was serious harm to the development of poultry industry, because of high disease incidence and death rate.Nowadays, anticoccidial drug was mainly uesed to cure chicken coccidiosis in clinic, but the pharmacodynamic action was cut down since the birth of the cocci dial drug-resistant strain. So, it was necessary to develop the anticoccidial drug with the characteristic of high performance, least toxicity and against drug-resistant strain.Adprin, a new anticoccidial drug was evaluated by clinical efficacy and pharmacokinetic characteristics.Therefor, the theoretical and experimental results would help reasonably veterinary clinical application.In order to screening the efficacy of anticoccidial drug, The six drugs:adprin, pyrimethamine,nifedipine,minoxidil,piperaquine, phosphate, allopurinol, which pharmacological mechanism were different were evaluated by the curative effect on artificial infected chicken coccidiosis. The test was evaluated by anticoccidia indexes (ACI), percent of optimum anticoccidial activity (POAA), reduction of lesion scores (RLS),relative oocyst production(ROP).The result indicated that adprin,which ACI was188.76,RLS was100%,ROP was0%,POAA was90.48%with70mg·kg-1dose. Pyrimethamine had little effects on anticoccidiosis and the others had no effect on chicken coccidiosis of artificial infection.Clinical effect on anticoccidiosis was respectively compared by different preparation and different dosage form adprin with other anticoccidial drugs. The result indicated that75mg·kg-1and85mg·kg-1Adprin were efficient coccidoistat, which ACI respectively were181.8,182.5,Relative weight gain of experiment chickens were88.3%and82.5%, survival rate were both100%.The result of curative test indicated that ACI of adprin with80mg·kg-1was190.56comparing with other anticoccidial drugs. In the test of drugs cooperating, anti-coccidiosis adprin (60mg·kg-1)salinomycin(60mg·kg-1) was better than single dose of60mg·kg-1salinomycin and salinomycin (60mg-·kg-1) with pyrimethamine (6.25mg·kg-1).ACI of monensin (121mg·kg-1) was91.19, which had no effect of againsting chicken coccidiosis. ACI monensin (70mg·kg-1) with adprin (60mg·kg-1) was110.97, which was higher than ACI monensin (100mg·kg-1) with adprin (60mg·kg-1), but had no synergistic effect. The result of different preparation of adprin showed that relative weight gain of adprin solution (80mg·-kg-1) group. Chickens was95.52%and ACI was195.52; relative weight gain of adprin pulvis (80mg·kg-1)group chickens was 83.02%and ACI was183.02. Therefore the efficacy of solution group was better than pulvis group. Relative weight gain of adprin (80mg·kg-1) which was treated by high temperature was85.54%.and ACI was185.54, as well as untreated group. ACI of adprin solution (40mg·kg-1) group and adprin suspensions (80mg·-kg-1) group respectively were137.61,150.14, both efficacy of anticoccidiosis were poor.The efficacy of adprin solution was evaluated comparing with toltrazuril by field test against flat chicken coccidiosis. The results showed that adprin group’s average weight gain was1.426kg, feed conversion ratio was2.22, survival rate was98.32%, toltrazuril group’s average weight gain was1.237kg, feed conversion ratio was2.51, survival rate was94.82%.Adprin concentration of the plasma was determinted by using high performance liquid chromatography in chicken. The detected conditions were that column was XDB-Ci8(250mm×4.6mm),mobile phase was Methanol-water (45:55/v:v),flow rate was1.0mL·-min-1, determine wavelength was254nm, column temperature was40℃. The date of adprin pharmacokinetic variables was analyzed by using absorption in two compartment open model with3P97PK program. The main pharmacokinetics parameters are as follows:Elimination half-lives of plasma adprin is2.414±0.252h; peaking time after dosing the drug to chickens is1.429±0.053h; the maximal plasma concentration is499.941±21.295ng-mL"1; areas under curve of drug is (2624.528±124.690)(ng-mL-1)·h respectively in chicken. The relative bioavailability of adprin in chicken is61.94%. The results suggested that pharmacokinetic of adprin were absorption quickly higher relative bioavailability, slow-elimination, bad-penetration and lower-residue in tissue in healthy chicken.