During the early postnatal period in calves various adaptational changes occur. These functional, morphological and also metabolic alteration are reflected by blood plasma protein changes as they are secreted and shed from many cells and tissues. Blood plasma protein pattern of an adult cattle differs in some respect when compared with neonatal calves. There exist a very few data concerning 2-D maps of neonatal calves blood plasma. The above prompted us to establish protein pattern of this biological fluid characteristic of healthy, 7 day old, Polish Black-and-White (Polish Friesian) breed calves. Blood plasma proteins of the isoelectric point ranging from 4.0 to 7.0 were analyzed by the aid of high resolution two-dimensional electrophoresis (2-DE). Subsequently, 79 excised protein spots corresponding to 23 different gene products were identified using matrix-assisted laser desorption/ionisation mass spectrometer (MALDI-TOF MS). Protein map obtained in the present study may be useful in assessing the changes in the calves blood plasma protein profiles occurring in response to different physiological and/or pathophysiological factors.