Disposition of ceftriaxone in goats (Capra hircus).

Pharmacokinetics of ceftriaxone was determined in goats after single dose intravenous and intramuscular administration at the dose rate of 20 mg/kg body weight. The drug concentrations in plasma samples were measured through High Performance Liquid Chromatography. Following intravenous administration, the apparent volume of distribution, area under curve, elimination half-life and total body clearance were 0.58 ± 0.04 L/kg, 77.51 ± 7.49 mg.h/mL, 1.50 ± 0.05 h and 4.50 ± 0.43 mL/min/kg, respectively.  Following intramuscular administration, the peak ceftriaxone plasma concentration of 21.51 ± 0.61 mg/mL was observed at 0.5h and the drug was detected up to 12h. The apparent volume of distribution, area under curve, elimination half-life & total body clearance following intramuscular injection were 0.53 ± 0.05 L/kg, 66.78 ± 4.90 mg.h/mL, 2.03 ± 0.09 h and 3.04 ± 0.34 mL/min/kg, respectively. The intramuscular bioavailability of ceftriaxone was 59.0 ± 4.0 %.  Ceftriaxone has favourable pharmacokinetics with moderate bioavailability in goats indicates that the drug can be used to treat susceptible infections in goats at the dose of 20 mg/kg.