Abstract

Bovine mastitis is an inflammation of the mammary gland with local and or symptoms that occasionally result in a systemic infection. This disease has a profound impact on animal welfare and milk quality, and the most costly disease affecting dairy cows. The bacteria Staphylococcus aureus is one of the most frequently isolated pathogens from both subclinical and clinical infections. This study was conducted to investigate the phenotypic and genotypic characterization of S. aureus involved in dairy cow mastitis in West Algeria. A total of 141 isolates of S. aureus isolated from quarter milk samples were collected from dairy cows. All retained S. aureus species contained gyr gene and were identified by molecular typing. The presence of resistance was evaluated in S. aureus. Staphylococci antimicrobial resistance was performed by detection of mecA gene. Several virulence factors including toxin of the Pantin Valentine leukocidin coding gene (pvl) were also investigated by polymerase chain reaction (PCR). Only one strain of S. aureus was mecA - and pvl+ gene.

Key words: Mastitis, S. aureus, Gyr A, PCR, mecA, pvl.