[Analyses of antimicrobial usage in 598 pig farms in Switzerland in 2017].

INTRODUCTION: Antimicrobial usage was analyzed in 598 Swiss pig farms as part of the SuisSano Health Program in 2017. Antimicrobial usage was calculated on the basis of the prescriptions of the veterinarians using the standard dosages DCDCH (Defined Course Dose for Switzerland) and the amount of active substance by weight. Usage was analyzed based on the active antimicrobial class, pharmaceutical form age category (suckling piglets, weaned piglets, fattening pigs, sows) and stock type (breeding farms, fattening farms, farrow-finish farms and sow pool systems (SPS). A total amount of 610 kg antimicrobials or 894,688 DCDCH standard doses were used. The proportion of Highest Priority Critically Important Antimicrobials (HPCIAs) of the total antimicrobial usage was 2.5% for breeding sows, 4.5% for piglets, and 2.7% for fattening pigs based on the number of treatments in DCDCH/animal/year. In contrast weaning piglets showed a calculated proportion of 26%, of which 18% was due to polypeptides (colistin). Suckling piglets produced in SPS stocks were treated significantly more frequently than suckling piglets from other farms (P.