contributions to the knowledge of chemical composition evolution in colostral milk

The aim of the paper was to evaluate the colostrum quality and changes in composition during the first three days postpartum. Researches were carried out on five Romanian Black and White primiparous cows. Samples of colostrum were collected at calving and at 4-hour interval for three days. Samples were analyzed for the percentage of protein, fat, lactose, dry matter nonfat and dry matter. The protein percentage dropped from 15.9 % at first milking after calving to 4.6 % at 72 hours after calving. Fat percentage also decreased from 8.3 % at first milking after calving to 4.3 % at 72 hours after calving. Lactose concentration in colostrums increased from 1.9 % at first milking after calving to 4.2 % at 72 hours after calving. The dry matter non fat concentration decreased from 19.8 % immediately after calving to 9.9 at 72 hours after calving. Total dry matter in colostral milk decreased from 28.1 % at first milking after calving to 14.2% at 72 hours after calving.