Zink is supplied to the organism of human and animal through the digestive tract mainly with foodstuff and forage. In the blood plasma, where Zink is predominantly tied to albumin, there is only 0.1 % from the total content of this microelement in the organism. This particle of Zink is used for quick support of tissues’ needs. Essential quantity of endogenous Zink is passed into the small intestine lumen by means of postprandial secretion from the pancreas and has to be reabsorbed into the blood. The process of reabsorbing insures the supplying of Zink which is necessary for homeostasis of Zink in the cells which is significant for regulation of this microelement balance. In the scientific sources there are a lot of works analyzing the physiological role of Zink in the human and animal organisms. As you know Zink takes part in a lot of molecular intracellular processes and is characterized by regulative impact on proliferation, differentiation and functional activity of different types of cells. It causes some physiological effects of the microelement, i.e.: the impact on the processes of growth and development of the organism, functioning of immune, nervous, reproductive and other systems. There is also the dependence between Zink exchange in the organism, circulatory system and respiratory system. This microelement is essential for reproductive function, skin functioning and mucous membranes, bone tissue, visual and taste systems, digestive organs and pancreas. Zink plays a defensive role at the conditions when the organism is impacted by different pathogenic agents. It is known that the decrease of Zink content in the blood plasma is developed during chronic and acute diseases and also as a response to stress, which is developed as a result of physical exertion and under the influence of external extreme factors. However, in the literature there are no data considering the impact of higher nervous function types on Zink content regulation.    

The esearches were carried out at the base PSP “Kolos”, Borodyanka village, Kyiv region on the apparently healthy cows of Ukrainian black and red breed of 2^nd and 3^rd lactation. Housing conditions, usage, ration and frequency of feeding for all the animals were equal. The types of higher nervous activity were determined according to the method of nutritive conditioned reflexes by G.V. Parashutin and T.V. Ipolitova modified by the department of physiology, pathophysiology and immunology of the animals of NULES of Ukraine. The essence of this method lies in the evaluation of motor response of animals to the place in the barn where forage was attached, speed of development and processing of conditional motor and nutritive reflex, the rate of orientation reflex and external inhibition.

The display of reaction was evaluated in nominal units from 1 to 4. According to the carried out researches of conditioned reflex activity 4 study groups of animals were formed each of them included 5 of the most typical representatives of higher nervous activity: I group – strong even motive type, II group – strong even inactive type, III group – strong uneven type, IV – weak type. The cows’ blood was chosen as the material for the research. Identification of Zink content was carried out according to the method of atomic emission spectrometry with inductively coupled plasma. The results of researches were processed according to the world recognized methods of statistics using Microsoft Excel. It is known that basic attribute of nervous processes is their power, evenness of agitation and inhibition and motion. The results of researches of conditioned reflex activity in cows are shown in the table 1. Animals of strong even motive type of higher nervous activity are characterized by the highest rates of basic attributes of cortical processes: their power estimated 3.0 of nominal units, evenness – 2.8 nominal units and agility – 2.8 nominal units. In the animals of strong even inactive type of higher nervous activity the power of nervous processes estimated less than 14.0 %, evenness – less than 7.0 % and agility – less than 64.0 % comparing to the animals of strong even motive type. In the cows of strong uneven type of higher nervous activity the power of nervous processes estimated less than 20.0 % in cows of strong even motive type and less than 7.0 % comparing to the cows of strong even inactive type. Cows of weak type of higher nervous activity were characterized by the lowest rates of basic attributes of cortical processes: power, evenness and agility were more than 3 times lower comparing to the cows of strong even motive type (p<0.01). According to the results of the researches it was estimated that the highest Zink content was found in the blood serum of animals of strong even motive type of higher nervous activity – 3.28±0,14 mg/l. Along with that we estimated the precise difference according to this value between representatives of strong even motive, strong uneven, weak types of higher nervous activity. In particular in animals of strong even motive type of higher nervous activity type the Zink content was higher by 14 % and 26 % respectively comparing to the rates of animals of strong even inactive and strong uneven types.

The animals of weak type of higher nervous activity were characterized by the lowest Zink content in the blood serum – 2.14±0.04 мg/l, which is by 25 % and 12 % lower than in animals of strong even inactive and strong uneven types of higher nervous activity. Thus the differences between cortical processes allow us to make an assumption that they do impact on the microelements exchange in the organisms of animals. It is known that the significant amount of Zink is accumulated by
β-cells of Langerhans’ islets where this given microelement takes part in the formation of hexamerous complexes of insulin in the secretarial granules. We reckon that precisely the impact of power, evenness and agility of nervous processes have an impact on the Zink exchange in the cows’ organism depending on the type of higher nervous activity. The content of Zink in the blood serum of cows depends on typological peculiarities of higher nervous activity. We estimated that there is the connection between Zink content in blood serum and three basic attributes of cortical processes.

Key words: higher nervous activity, cattle, Zink, blood serum.