on-farm culturing for mastitis pathogens is a valuable management tool at the Midwest Dairy Institute, Milbank, S.D. The dairy uses a culturing system to detect the presence of a Staph or Strep   species in a milk sample that has incubated on a culture plate. The results help them make appropriate treatment decisions.

However, sometimes the culturing system mistakenly identifies a cow as having Staph. aureus when she really doesn’t. To overcome this problem, they check all Staph-suspect cows for a hard or “meaty” quarter and a somatic cell count above 500,000, says Kelly Hummel, dairy operations manager. If a cow possesses these characteristics, she heads to a separate Staph-cow pen that is milked last. If she doesn’t, she goes back to her usual pen.