title: In vitro susceptibility of ceftiofur against Streptococcus equi subsp zooepidemicus and subsp equi isolated from horses with lower respiratory disease in Europe since 2002.
abstract: In vitro activity of ceftiofur and six other antimicrobial agents was evaluated against 79 Streptococcus equi subsp zooepidemicus isolates collected from horses with respiratory disease in Europe during 2007 and 2008. In addition, the in vitro activity of ceftiofur and other antimicrobial drugs was assessed against 59 S. equi subsp zooepidemicus and 49 S. equi subsp equi isolates collected by veterinary diagnostic laboratories in Europe from 2002 to 2006. The lowest concentration of ceftiofur that inhibited the growth of 90% of the isolates (MIC90) was 0.12 microg/ml, with the Clinical Laboratory Standards Institute-approved susceptible breakpoint set at ≤ 0.25 microg/ml for ceftiofur against S. equi subsp zooepidemicus. The MIC90 values remained consistent when comparing the isolates collected from diagnostic laboratories or from the field study.
authors.affiliation: Microbial Research Inc., Fort Collins, CO 80524, USA.
authors.forename: Donald
authors.initials: D
authors.lastname: Bade
authors.forename: Ellen
authors.initials: E
authors.lastname: Portis
authors.forename: Caroline
authors.initials: C
authors.lastname: Keane
authors.forename: John
authors.initials: J
authors.lastname: Hallberg
authors.forename: Lawrence
authors.initials: L
authors.lastname: Bryson
authors.forename: Mike
authors.initials: M
authors.lastname: Sweeney
authors.forename: Pamela
authors.initials: P
authors.lastname: Boner
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D002511:Cephalosporins / Q000494:pharmacology*; D024881:Drug Resistance, Bacterial; D005060:Europe / Q000453:epidemiology; D006734:Horse Diseases / Q000382:microbiology*; D006736:Horses; D008826:Microbial Sensitivity Tests; D012141:Respiratory Tract Infections / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary; D013290:Streptococcal Infections / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary*; D018502:Streptococcus equi / Q000187:drug effects* / Q000302:isolation & purification*; D013997:Time Factors
chemical_list: D000900:Anti-Bacterial Agents; D002511:Cephalosporins; C053503:ceftiofur