Characteristics of Escherichia coli Isolated from Bovine Mastitis Exposed to Subminimum Inhibitory Concentrations of Cefalotin or Ceftazidime

Table 4

Antimicrobial susceptibility profiles of the Escherichia coli isolates recovered after induction with ceftazidime.

	Resistant E. coli isolates
Antimicrobial	Derived from E4	Derived from E11	Derived from E21
Cefalotin	CAZ-1/-2/-3/-4/-5/-6/-7/-8/-9	CAZ-1/-2/-3/-4/-5/-6/-7/-8/-9	CAZ-1/-2/-3/-4/-5/-6/-7/-8/-9
Cefoxitin	CAZ-4/-5/-6/-7/-8/-9	CAZ-3/-4/-5/-6/-7/-8/-9	CAZ-4/-5/-6/-7/-8/-9
Ampicillin	CAZ-2/-3/-4/-5/-6/-7/-8/-9	CAZ-1/-2/-3/-4/-5/-6/-7/-8/-9	CAZ-1/-2/-3/-4/-5/-6/-7/-8/-9
Amoxicillin/; clavulanic acid	CAZ-2/-3/-4/-5/-6/-7/-8/-9	CAZ-1/-2/-3/-4/-5/-6/-7/-8/-9	CAZ-1/-2/-3/-4/-5/-6/-7/-8/-9
Kanamycin	CAZ-1/-2/-3/-4/-5/-6/-7/-8/-9	CAZ-2/-3/-4/-5/-6/-7/-8/-9	CAZ-1/-2/-3/-4/-5/-6/-7/-8/-9

All E. coli isolates had intermediate resistance to kanamycin.