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Multiplex PCR Assay for Typing of Staphylococcal Cassette Chromosome Mec Types I to V in Methicillin-resistant Staphylococcus aureus
Published on: September 5, 2013
Fine-structure molecular epidemiological analysis of Staphylococcus aureus recovered from cows
J R Fitzgerald1, W J Meaney, P J Hartigan
1Department of Physiology, Trinity College, Dublin, Ireland.
Epidemiology and Infection
|November 18, 1997
Summary
Few specialized Staphylococcus aureus clones cause bovine mastitis globally. These specific bacterial clones, identified through genetic typing, are found in both the USA and Ireland, suggesting a widespread issue in dairy herds.
Area of Science:
- Veterinary Microbiology
- Bacterial Genetics
- Epidemiology
Background:
- Staphylococcus aureus is a significant pathogen causing bovine mastitis.
- Understanding the genetic diversity and clonal distribution of S. aureus is crucial for effective disease control in dairy cattle.
Purpose of the Study:
- To characterize Staphylococcus aureus isolates from bovine sources in the USA and Ireland.
- To investigate the clonal relationships and geographic distribution of S. aureus involved in bovine mastitis.
Main Methods:
- Multilocus enzyme electrophoresis (MLEE) for bacterial typing.
- Ribotyping and random amplified polymorphic DNA polymerase chain reaction (RAPD-PCR) for genetic characterization.
- Comparative analysis of typing results from two independent laboratories.
Main Results:
- MLEE identified 10 electrophoretic types (ETs), ribotyping yielded 13 types, and RAPD-PCR revealed 12 types.
- A globally distributed clone (ET3) was identified, represented by six different combinations of ribotypes and RAPD types.
- Bovine S. aureus clones from Ireland were linked to mastitis cases in US dairy cows.
Conclusions:
- A limited number of specialized S. aureus clones are responsible for most bovine mastitis cases.
- These dominant bovine mastitis clones exhibit a wide geographic distribution, impacting dairy herds internationally.
- Findings support the hypothesis of clonal expansion and dissemination of specific S. aureus lineages in cattle.
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