Staphylococcus aureus

Staph aureus commonly produces long-lasting infections persisting through the lactation and into subsequent lactations.  Staph aureus infected cows should be identified and milked last or milked with a separate unit from those used on uninfected cows. Antibiotic therapy during lactation usually does not eliminate infection.  Infected quarters not responding to a single regimen of therapy are generally unresponsive to additional lactation treatment, regardless of culture and sensitivity tests.  Dry cow therapy may givee better results than treatment during lactation, but even then, chronic infections can persist into subsequent lactations.  Staph aureus infection status of cows should be one of the considerations when making culling decisions.