The overuse of antibiotics in livestock contributes to the antibiotic resistance pandemic. The assessment of the actual antibiotic consumption is crucial in limiting the expansion of the problem effectively. The aim of this study was to provide the first qualitative and quantitative analysis of antimicrobial usage using data from paper-based registers on dairy and beef farms located in the Umbria region, Italy. Antimicrobial therapies of a one-year period were collected from 101 farms with at least 50 cattle each. Defined daily doses (DDDvet) and defined course doses (DCDvet) were calculated per administration route and antimicrobial class. The total courses administered were fewer in beef (330.7 × 10-3 DCDvet/year) than in dairy farms (1034.1 × 10-3 DCDvet/year). The use of the highest priority critically important antimicrobials (HPCIAs) was higher (p = 0.0033) in dairy than in beef herds. In terms of DDDvet, the parenteral fluoroquinolone administration ranked second and fourth on dairy and beef farms, respectively; the consumption of beta-lactams was ten times higher on dairy than on beef farms. Our results confirm that intensive dairy management practices are associated with increased antibiotic consumption and highlight the necessity to strengthen the existing stewardship programs by involving all stakeholders in effective antimicrobial resistance reduction plans.
Keywords: DCDvet; DDDvet; antibiotic consumption (AMC); antibiotic use; antimicrobial resistance; beef cattle; dairy cattle.