title: Disposition kinetics of gentamicin in normal and endometritic cows using a microbiological assay.
abstract: Gentamicin concentrations in serum, urine and milk were assayed microbiologically after intramuscular and intrauterine administrations in normal and endometritic cows. Following intramuscular injections of 5 mg gentamicin/kg b. wt. 3 times daily for three consecutive days, the highest serum concentrations occurred 1 h post administration of each dose with absorption half-lives [t0.5(ab)] ranging from 0.23 to 0.30 h for normal cows and from 0.21 to 0.29 h for endometritic cows. The elimination half-lives [t0.5(beta)] ranged from 2.51 to 2.95 h (normal cows) and from 2.71 to 3.29 h (endometritic cows). Following intrauterine administration of 4 mg gentamicin/kg. b. wt. once daily for three consecutive days, the drug peaked in serum 2 h after each dose with [t0.5(ab)] ranging from 0.47 to 0.52 h (normal cows) and from 0.57 to 0.68 h (diseased cows), while the drug was eliminated faster in endometritic cows than in normal cows. The mean systemic bioavailability were (70%) and (30%) after intramuscular and intrauterine administration, respectively. To compare serum concentrations, gentamicin was assayed in urine and milk in high and low concentrations, respectively.
authors: M G
authors: MG
authors: el-Sayed
authors: M E
authors: ME
authors: Hatem
authors: A A
authors: AA
authors: el-Komy
mesh_terms: D000818:Animals; D001681:Biological Assay; D001682:Biological Availability; D002417:Cattle / Q000378:metabolism*; D002418:Cattle Diseases / Q000378:metabolism*; D004716:Endometritis / Q000378:metabolism / Q000662:veterinary*; D005260:Female; D005839:Gentamicins / Q000008:administration & dosage / Q000493:pharmacokinetics*; D006207:Half-Life
chemical_list: D005839:Gentamicins