DISPOSITION KINETICS OF AMPICILLIN IN WHITE LEGHORN HENS

The pharmacokinetics and tissue disposition of ampicillin after single i.v. dose (50 mg/kg bw) was studied in 2 groups of White Leghorn (WLH ) hens. The plasma concentration ranged from 0.14+/-0.008 to 18.95+/-1 .63 mug/ml for 12 hr. The mean values of pharmacokinetic parameters fo r t1/2 alpha, t1/2 beta Vd(area), CL(B) and T/P ratio were 0.44+/-0.02 hr, 2.66+/-0.11 hr, 7.17+/-0.80 litre/kg, 30.50+/-2.38 ml/kg/min and 2.67+/-0.19 respectively. The mean value of K12, K21, K10, and K12/K21 was 0.43+/-0.04 hr-1, 0.43+/-0.03 hr-1, 0.95+/-0.03 hr-1 and 1.01+/-0 .05 hr respectively. The level of drug in bile was 35.99+/-1.81 mug/ml and 37.17+/-2.34 mug/ml at 4 and 24 hr post-drug administration respe ctively. Ampicillin residual level was determined in different organs and skeletal muscles of the birds at 4 and 24 hr post-administration. Dosage regimen based on the kinetics of drug has been suggested for op timal clinical efficacy.