Cephapirin usage at dry-off in Holstein and Simmental cows in relation to udder health, parity, and production level

The research aimed to evaluate cephapirin usage at dry-off in Holstein and Simmental dairy cows, with respect to udder health status, parity, and milk production level. The analysis was based on a large dataset derived from routine milk records. The cows were classified by mastitis status (clinical, subclinical, and healthy), parity, and average production level. The results indicate that a considerable proportion of cephapirin was administered unnecessarily to healthy cows, those without clinical signs of mastitis or elevated somatic cell counts. Across both breeds, over 55% of the total antibiotic quantity was used in cows classified as healthy. This practice was especially prevalent among primiparous cows and those in lower production groups, reflecting a widespread reliance on blanket dry cow therapy (BDCT). Further- more, breed-specific differences were also observed: Holstein cows demonstrated a more pronounced shift toward therapeutic antibiotic use as parity and production level increased, whereas Simmentals showed a more gradual transition. Nevertheless, across all parity and production categories, substantial antibiotic application in uninfected cows persisted regardless of breed. These results, based on a 10-year analysis of test-day records, indicate the need to implement selective dry cow therapy (SDCT), which targets only cows likely to have intramammary infections, on the basis of somatic cell counts and clinical indicators. Two refined datasets were prepared for this purpose, including over 2.5 million test-day records for Holstein cows and more than 2.8 million for Simmental cows. Adjusted antibiotic use according to cow parity, production level and breed could reduce unnecessary antimicrobial treatments without compromising udder health or milk production in subsequent lactations. This approach promotes rational antibiotic use and supports sustainable dairy production in line with EU Regulation 2019/6 and broader efforts to combat antimicrobial resistance (AMR).