Effects of two simulated oxytetracycline dosing regimens on horizontal transfer of antimicrobial resistance plasmids in an in vitro pharmacodynamic model.

Objective: To evaluate the impact of oxytetracycline exposure on horizontal transfer of an antimicrobial resistance plasmid.

Sample: Populations of Salmonella enterica subsp enterica serovar Typhimurium and Escherichia coli.

Procedures: Mixed populations of plasmid donor (Salmonella Typhimurium) and recipient (E coli) bacteria were assigned to 1 of 2 simulated oxytetracycline dosing regimens (high peak concentration-short elimination half-life [HC-SHL] or low peak concentration-long elimination half-life [LC-LHL]) or served as untreated control replicates.