title: An atypical Staphylococcus aureus intramammary infection in a dairy herd.
abstract: An atypical Staphylococcus aureus (S. aureus) strain, isolated in a dairy herd over an 8 month period, was examined. The S. aureus strain was clumping factor negative, weakly heat-resistant deoxyribonuclease positive and produced narrow zones of double haemolysis. In total, 57 quarter infections were observed. Prevalence data per month, calculated as the percentage of quarters infected with this atypical S. aureus strain varied from 7.5% to 17.7% and the new infection rate varied from 0.14 to 0.55. In routine bacteriology, the large number of quarters infected with the atypical S. aureus could easily be misclassified as quarters infected with non-aureus staphylococci.
authors.affiliation: Faculty of Veterinary Medicine, Department of Obstetrics, Reproduction and Herd Health, Ghent, Belgium.
authors.forename: H
authors.initials: H
authors.lastname: Laevens
authors.forename: L A
authors.initials: LA
authors.lastname: Devriese
authors.forename: H
authors.initials: H
authors.lastname: Deluyker
authors.forename: J
authors.initials: J
authors.lastname: Hommez
authors.forename: A
authors.initials: A
authors.lastname: de Kruif
mesh_terms: D000818:Animals; D015373:Bacterial Typing Techniques / Q000662:veterinary; D002417:Cattle; D003030:Coagulase / Q000032:analysis; D003851:Deoxyribonucleases / Q000032:analysis; D005260:Female; D006461:Hemolysis; D015994:Incidence; D008414:Mastitis, Bovine / Q000453:epidemiology / Q000382:microbiology*; D008892:Milk / Q000382:microbiology; D015995:Prevalence; D013203:Staphylococcal Infections / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary*; D013211:Staphylococcus aureus / Q000145:classification* / Q000201:enzymology / Q000302:isolation & purification
chemical_list: D003030:Coagulase; D003851:Deoxyribonucleases