DYNAMICS OF HEMOSTATIC FUNCTIONS OF PLATELETS AND BLOOD VESSELS IN PIGLETS DURING THE PHASE OF PLANT NUTRITION

Hemostasis and, first of all, platelets and vessel walls play a serious role in maintaining a stable state of the organism of farm animals. The expression of their hemostatic properties in piglets at the end of early ontogenesis still needs to be clarified, as they are very significant for microcirculation and intensity of anabolism in all internal organs. Objective: to determine in the primary hemostasis of piglets undergoing the phase of vegetable feeding, the expression of platelet aggregation functions and disaggregation activity of vascular walls. Thirty-two healthy piglets, left for breeding, of the Large White breed, were observed with evaluation of the registered indicators: on the forty-first day, on the ninetieth day, on the one hundred and fiftieth day, on the two hundredth day and on the two hundred and thirtieth day of their life. In the blood of piglets the content of the amount of acylhydroperoxides and substances reacting with thiobarbituric acid was determined, and the level of its antioxidant properties was evaluated. The level of platelet aggregation was elucidated under in vitro conditions using visual micromethod. For this purpose, a number of standard aggregation inducers at a standard dose were used. Also the state of platelet aggregation was evaluated under conditions of intravascular blood flow in the course of phase-contrast microscopy. Vascular disaggregation capabilities were revealed by calculating the value of vascular antiaggregation index. The levels of β-thromboglobulin, thromboxane B2, 6-keto-PGF1α by radioimmunologic method and the amount of nitric oxide metabolites (nitrates and nitrites) by standard method were recorded in the blood of animals. The data were processed by Student’s criterion. In piglets at the end of early ontogenesis a gradual reduction in the blood level of peroxidation products was found. This was caused by strengthening of antioxidant capabilities of blood with age. This situation creates in piglets at this age optimal conditions for a great preservation of platelet membranes and vascular endotheliocytes. It can be considered that in these productive animals at the end of early ontogenesis the increase in platelet activity is fully balanced by the increasing hemostatic capacity of vessels, which provides a strict optimum of microcirculation conditions necessary for growth and development of the organism.