Micro-organism | Species | Drug of choice | Alternative | Comments |
---|---|---|---|---|
Streptococci | Streptococcus agalactiae Streptococcus dysgalactiae Streptococcus uberis | Penicillin G | IMM treatment preferable. | |
Enterococci | According to susceptibility testing | Prognosis for bacteriological cure is poor | ||
Staphylococci | Staphylococcus aureus Coagulase negative staphylococci β-lactamase -ve | Penicillin G | Combination treatment in S. aureus mastitis | |
Staphylococcus aureus Coagulase negative staphylococci β-lactamase +ve | No antimicrobials | Cloxacillin Macrolides Lincosamides | IMM and/or systemic treatment depending on the drug used. Prognosis for S. aureus mastitis is poor. Cloxacillin may select for methicillin-resistant | |
Coliforms | Escherichia coli Klebsiella spp. | No antimicrobials | Fluoroquinolones Cephalosporins | Antimicrobials necessary in serious cases and during puerperal period |