Herd-level association between antimicrobial use and antimicrobial resistance in bovine mastitis Staphylococcus aureus isolates on Canadian dairy farms

摘要: Surveillance of antimicrobial use and resistance is needed to manage in bacteria. In this study, data were collected on Staphylococcus aureus (n=562), isolated from intramammary infections (sub)clinical mastitis cases 89 dairy farms 4 regions Canada [Alberta, Ontario, Quebec, the Maritime Provinces (Prince Edward Island, Nova Scotia, New Brunswick)]. Dairy producers asked deposit empty drug containers into specially provided receptacles, rate was calculated quantify use. Minimum inhibitory concentrations determined using Sensititer bovine plate system (TREK Diagnostic Systems Inc., Cleveland, OH), containing antimicrobials commonly used for treatment control. Multivariable logistic regression models built determine herd-level risk factors penicillin, ampicillin, pirlimycin, penicillin-novobiocin combination, tetracycline sulfadimethoxine Staph. isolates. Intramammary administration combination dry cow therapy associated with penicillin ampicillin [odds ratio (OR): 2.17 3.10, respectively]. Systemic (OR: 1.63). pirlimycin lactating as well 2.07). Average herd parity 3.88 0.02, respectively). size also 1.02). herds region had higher odds lower than Quebec 2.18 0.19, Alberta 0.04 0.08, Ontario 0.05 0.33, Herd-level certain administered control, such systemically florfenicol, positively pathogens field conditions. Differences outcomes across observed.