Failure to do this results frequently in a more serious mastitis problem due to mechanical introduction of new infectious agents during the treatment process. Treatment duration should be at least 3 days or prolonged 1 more day after clinical signs have completely disappeared. Response to treatment varies considerably depending on the organism, duration of infection, cow's immune response, and other factors. Infections caused by Staphylococcus aureus, for example, do not respond well during lactation but might respond better to dry-cow treatment. A decision to stop milking the cow before the end of a normal lactation might be necessary to allow more intense treatment and improved opportunity for a positive response.
Subclinical mastitis is the most common type.
Detection of subclinical mastitis requires the use of special tests since no signs other than lower production may be evident. While the CMT is an important tool in monitioring progress of the control program, treatment should not be based solely on this criteron. Treatment Based on Culture and Antibiotic Susceptibility. Many cows respond fairly well when treatment is administered early and long enough if the organism is susceptible to the drugs used. To reduce guesswork, it is desirable to sample infected clinical or CMT-positive quarters before treatment to determine the specific pathogen present and its susceptibility to certain drugs.