ELISA DETERMINATION OF PLASMIN AND PLASMINOGEN IN MILK OF INDIVIDUAL COWS MANAGED WITHOUT THE DRY PERIOD

To determine by ELISA the variation of plasmin (PLM) and plasminogen ( PLG) with lactation and the origin of this variation, 18 high-yielding Holstein cows were milked during 1 year, throughout pregnancy. PLM, P LG, immunoglobulin G (IgG), serumalbumin (BSA), somatic cell (SCC), pr otein content (PC) and milk yield (MY) were determined in these indivi dual milks. It was observed that parturition is accompanied by a drama tic increase in PLM, PLG, IgG, BSA, PC and SCC and with decrease in MY . The intense increase in the blood-originating proteins in milk prove s that carving is characterized by an important influx of blood into m ilk.