Plasminogen activator activity in secretions from clinically normal, mastitic, lactating and dried-off udders of dairy cows.

Using the composite fibrin plates method, plasminogen activator (PA) activity was found in secretions from clinically normal, mastitic, lactating and dried-off udders of dairy cows. The possible involvement of the fibrinolytic system in the physiology and pathology of the bovine mammary gland is discussed.