Molecular Typing of Methicillin Resistant Staphylococcus aureus Strains Isolated from Cows and Farm Workers

The aims of this study were to isolation and identification of methicillin resistant Staphylococcus aureus (MRSA) from mastitic cow milk and nasal swabs of cows and related workers, investigation presence of Panton-Valentine leucocidin (PVL) genes and molecular characteristics of these isolates. One hundred forty five mastitic milk samples were obtained from of 56 cows and nasal swabs were collected from these cows and 34 farm workers. MRSA isolates were recovered by pulsed field gel electrophoresis (PFGE), staphylococcal chromosomal cassette (SCC) mec typing, staphylococcal protein A (spa) typing, multilocus sequence typing (MLST). A total of 12 MRSA were identified. All strains were PVL genes negative. PFGE analysis of all 12 MRSA isolates produced four distinct pulsotypes (PT) designated as PT A-D. The PT A (7 strains) detected sequence type (ST) were ST 239, spa type t030 and SCCmec III except one. The PT B (3 strains) were ST1294, t459 and SCCmec III, the PT C (1 strain) was ST1940, t660, SCCmec III detected, the PT D (1 strain) was ST737, t542, SCCmec II. Consequently, it can be said that t030 and ST239 was the most common spa and MLST types which isolated from cow milk and nasal swabs and nasal swabs from workers of these farms in Aydin region, Turkey.