The effect of a metaphylactic pulse dosing in-feed antimicrobial strategy on finishing pig health and performance

Abstract

Methods: Barrows (n = 1092) from a herd naturally infected with endemic respiratory pathogens were assigned by pen to one of three treatment groups: a “Continuous” group that received alternating doses of tiamulin plus chlortetracycline on weeks 2,4,7,10, and 13 interspersed with a reduced concentration of chlortetracycline alone during weeks 3,5,6,8,9,11, and 12; a “Pulse” group, which received in-feed pulse dosing with tiamulin plus chlortetracycline only in weeks 2,4,7,10, and 13 with no medication during the other study weeks; or nonmedicated Controls that received nonmedicated feed throughout the trial. Growth performance, survivability, and seroconversion to various pathogens were measured.