Physiological properties of platelets in Dutch calves during the milk nutrition phase

Platelet activity is very important for the physiology of hemostasis in cattle and metabolic processes in tissues. It has great biological significance in the process of active growth and development of animals. Under observation were taken 43 calves of the Dutch breed, which had no violations, in their objective status. Animals were examined at the age of 11 days, 15 days, 20 days, 25 days and 30 days. For this, standard biochemical, hematological and statistical methods of research were used. During the observation, the calves found a tendency to weaken the process of platelet aggregation in vitro in vivo. This was accompanied by their tendency to increase in their blood inactive platelets. Against this background, the total level of active platelets and the number of platelet aggregates of all sizes in it decreased in the blood of animals. The revealed changes were caused in the observed calves by a developing weakening of thromboxane synthesis in platelets, a decrease in the content of adenosine phosphates in their granules and a decrease in the degree of their secretion. During the observation period, a certain amount of actin and myosin in the platelets of animals tended to decrease. This was accompanied by some weakening in the examined calves of additional selfassembly of actin and myosin molecules in platelets during their aggregation. Calves of the Dutch dairy breed are characterized by a high degree of functional perfection of platelets, which provides conditions for the optimum microcirculation necessary for the formation of high future productivity of these animals.