| Abstract: | The in vitro susceptibility of Escherichia coli, Salmonella sp, Pasteurella multocida, and Pseudomonas aeruginosa strains isolated from young calves and their environment to kanamycin and its semisynthetic derivative--amikacin, was compared by the tube dilution method. The minimal inhibitory concentration of amikacin was two- to fourfold lower than the minimal inhibitory concentration of kanamycin for the Salmonella group B, Ps aeruginosa and P multocida strains examined, whereas the E coli and Salmonella group D strains were eqaully susceptible to the 2 antibiotics. The concentrations of amikacin and kanamycin in the serum of calves after single intramuscular injections at 10, 25, and 50 mg/kg were determined, and differences between the 2 antibiotics were not observed. Intramuscular dosage schedules were calculated, based on the sensitivity of the different bacterial strains and the duration of effective serum drug concentrations. |
