Mastitis is the inflammatory reaction of the udder tissue due to physical condition or microorganisms infections, what these microorganisms (bacteria) ?
Infection is usually caused by Staphylococcus aureus. Infectious pathogens commonly associated with mastitis are Staphylococcus aureus, Streptococcus spp., and Gram-negative bacilli such as Escherichia coli.
Common: St. aureus, Str agalactiae, Str. dysgalactiae.
Environmental: Str. uberis, E.coli, K.pneumoniae, Coagulase Negative Stapylococcus, Trueperella pyogenes
Uncommon environmental: Yeast, Prothoteca spp, Lactococcus spp, other Enterobacteriacea, Other heamolytic Streptococci (Str. canis, Str. zooepidemicus, Str dysgalactiae equisimilis) and and...practically every other bacteria...