Molecular epidemiology and antimicrobial susceptibility of Escherichia coli and Staphylococcus aureus isolated from bovine mastitis
molecular typing, MPEC, dairy cattle, zoonosis, multidrug resistance
Mastitis is the most important and defiant disease in dairy industry, causing several economic losses. The losses are mainly related with milk production decrease, costs with diagnosis and treatment, veterinary service, discarded milk, future milk production loss, reduced reproduction and premature culling and replacement of mastitis cows. Traditionally, the disease is classified as “contagious mastitis” or “environmental mastitis”, according to the agent involved, primary reservoir and mode of transmission. Pathogens classified as contagious are transmitted during milking process and normally cause infection without clinical signs, only with increase in somatic cells contain (SCC). An example of contagious pathogen is Staphylococcus aureus. Environmental mastitis pathogens, on the other hand, are present in the environment of dairy farms and the disease usually has intense clinical signs, which can lead the animal to death. Escherichia coli is usually a bacteria with environmental behavior. To understand the dynamic of the transmission, reservoirs and sources of infections and to proposal control measures to mastitis pathogens, it is critical to perform classical and molecular epidemiological studies, which allow the assessment of the frequency, distribution and risk factors associated with the disease, as well as the definition and characterization of the isolates involved. In these studies, it is also possible to evaluate the microevolution of the pathogen and the interface between specific-human and specific-animal strains. Antimicrobial susceptibility tests, in turn, allows evaluate the evolution of bacterial resistance to antimicrobial drugs and its implications to human and animal health. In front of that, the objective of this study is to assess strains of S. aureus and E. coli using molecular typing techniques, as multi-locus sequence typing (MLST) and REP-PCR, and perform the antimicrobial susceptibility profile of these same strains.
molecular typing, MPEC, dairy cattle, zoonosis, multidrug resistance