The technical definition of mastitis is “inflammation of the mammary gland” but on a practical basis, almost all bovine mastitis is caused by bacteria. Appropriate mastitis control is based on knowledge of the etiology, thus identification of pathogens is a fundamental aspect of mastitis control programs. Mastitis occurs after an infective dose of a pathogenic organism passes through the streak canal and progresses to a subclinical or clinical state but many intramammary infections are spontaneously cured as a result of the cows immune response.
However, detection of mastitis is based on observation of inflammation that occurs as a result of that response. Thus, recognition of mastitis occurs after the immune response and in many instances, culture of milk samples obtained from inflamed quarters may not result in bacterial growth. The use of molecular techniques to identify bacterial DNA from milk samples is increasingly used in an attempt to improve diagnosis.
In the newest article Facts about using PCR or other new tests to diagnose mastitis, UW-Extension Milk Quality Specialist Pam Ruegg discusses practical aspects of using these tests in mastitis control programs.
Source:uwex.edu