title: Prevalence and antibiotic resistance of mastitis pathogens isolated from dairy herds transitioning to organic management.
abstract: Changes in udder health and antibiotic resistance of mastitis pathogens isolated from dairies upon conversion from conventional to organic management over a 3-year period was studied. Coagulase-negative staphylococci (CNS) were the most prevalent mastitis pathogens isolated. CNS were significantly less resistant to β-lactam antibiotics when isolated from milk after the herd transitioned to organic management. Cessation of the use of antimicrobial therapies in dairies in combination with organic management could lead to a reduction in the antimicrobial resistance of mastitis pathogens.
authors.affiliation: Department of Microbiology, College of Veterinary Medicine and BK21 Program for Veterinary Science, Seoul National University, Seoul 151-742, Korea.
authors.forename: Young Kyung
authors.initials: YK
authors.lastname: Park
authors.forename: Lawrence K
authors.initials: LK
authors.lastname: Fox
authors.forename: Dale D
authors.initials: DD
authors.lastname: Hancock
authors.forename: Wade
authors.initials: W
authors.lastname: McMahan
authors.forename: Yong Ho
authors.initials: YH
authors.lastname: Park
mesh_terms: D000667:Ampicillin / Q000494:pharmacology; D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D002417:Cattle; D002512:Cephalothin / Q000494:pharmacology; D003023:Cloxacillin / Q000494:pharmacology; D004352:Drug Resistance, Microbial; D005260:Female; D007774:Lactation; D008414:Mastitis, Bovine / Q000382:microbiology*; D008826:Microbial Sensitivity Tests; D058871:Organic Agriculture; D010406:Penicillins / Q000494:pharmacology; D015995:Prevalence; D013203:Staphylococcal Infections / Q000382:microbiology / Q000662:veterinary*; D013210:Staphylococcus / Q000187:drug effects* / Q000302:isolation & purification*
chemical_list: D000900:Anti-Bacterial Agents; D010406:Penicillins; D000667:Ampicillin; D003023:Cloxacillin; D002512:Cephalothin