Inhibition of the proteinase activity in mastitic milk

The antiproteolytic activity of selected proteinase inhibitors was studied in mastitic bovine milk and urokinase-activated normal milk using a caseolytic agar diffusion assay. The inhibition profiles of mastitic milk and urokinase-activated milk were compared with those of purified proteinases. The proteinase inhibition profile of mastitic milk did not resemble that of any of the pure proteinases, indicating a mixed type of proteinase system in mastitic milk. The trypanocidals diminazene (equivalent to Berenil) and pentamidine (equivalent to Lomidine), together with aprotinin (Trasylol), showed most promise when considering possible applications in mastitis to break up the proteolytic cascade within the inflamed udder.