Whatever happened to mastitis pathogenesis?

Abstract

AbstractWe have learned a lot about infections of the mammary gland of dairy cows from experimental investigations of the pathogenesis of the various diseases. The understanding gained has contributed to huge successes in reducing the prevalence of infection in properly managed dairy herds. Now descriptive studies using DNA technologies reject previous concepts of mammary gland sterility by default. Bacteria, at least markers of genes, of many genera are reported even from absolutely healthy mammary glands. This may be a technological artefact. No direct evidence exists because experimental studies of infection are no longer fashionable. A regeneration of the lost arts in the pathogenesis of infection is essential to separate truth from conjecture and deal with coming challenges from rapidly changing farm systems and the reduction in access to antimicrobial drugs. In this Opinion Paper I argue for a return to experimental approaches that construct hypotheses, and then test them, in intramammary disease research.