Pharmacokinetic properties of florfenicol in Egyptian Goats

The single-dose disposition kinetics of florfenicol was determined in healt hy, non-lactating Egyptian goats, after its intravenous (iv) and intramuscu lar (im) administration at 20 mg kg(-1) b.wt. Drug concentrations in serum and urine were determined using microbiological assay method and data was s ubjected to a kinetic analysis. Florfenicol concentrations in serum decreas ed in a bi-exponential manner after intravenous administration with distrib ution (t(1/2)alpha) and elimination (t(1/2)beta) half-lives of 10.256 +/- 0 .938 and 56.237 +/- 3.102 minute, respectively. The steady-state volume of distribution (Vdss) and total body clearance (Cl-tot) were 3.413 +/- 0.304 l kg(-1) and 3.306 +/- 0.333 l kg h(-1). After intramuscular administration , the peak serum concentration (Cmax) was 0.859 +/- 0.025 mu g ml(-1), achi eved at (Tmax) 1.220 + 0.045 h. Florfenicol was detected in urine up to 24 and 96 hour after iv and im administration, respectively. The extent of the protein binding and systemic bioavailability of florfenicol were 22.45 +/- 1.727% and 65.718 +/- 3.372 %, respectively.