Mastitis is considered a great problem in dairy farming. Antimicrobials are often used to contribute to increase the selective pressure of microorganisms that are resistant to the main drugs. Animal World Health Organization aims to protect animal and human health against the risk of antimicrobial resistance from sick animals treatments.This study aims to identify and characterize clonal profile, virulence factors and antimicrobial resistance factors in Staphylococcus spp. isolated from cattle milk of animals with subclinical mastitis of diferent zones in Brasil. The samples will be obtained by "Embrapa Gado de Leite" from six diferent brazilian states including Paraná, Santa Catarina, Rio Grande do Sul, Minas Gerais, São Paulo and Pernambuco. This study includes all Staphylococcus spp. strains that shows to be oxacilin resistant by the disc diffusion method. This samples will be phenotypic and genotypic identified folowed by an investigation of enterotoxins and biofilm genes encoding presence. Thereafter, the study will include the determination of oxacilin resistance by identifying the mecA and homologue mecA genes (mecC) and the vancomycin resistance screening. Positive isolates to biofilm and toxin genes encoding presence will pass trought the qRT-PCR techinique to determinate these virulence factors expression. Furthermore the Staphylococcus spp. clonal profile will be investigated using the Pulsed Field Gel Electrophoresis (PFGE) technique and the Multilocus Sequence Typing (MLST) technique; this last one by typing the prevalent clones. Thus, the staphylococci species clonal profile isolated from chattle milk may contribute to understand the present strains standarts on different herds, allowing measures to prevent and control the spread of pathogenic and multiresistant staphylococci clones in different brazilian zones.
News published in Agência FAPESP Newsletter about the scholarship: