Peroxide oxidation processes play a leading role in ensuring the motility, survival and fertilizing ability of sperm. A special role is given to limiting antioxidants (vitamins, amino acids, microelements). Therefore, the development of standardized feeding programs to provide antioxidant nutrition is one of the effective methods of reproductive biotechnology. The aim of the study was to determine the effect of copper citrate on the quality of sperm production and the formation of prooxidant-antioxidant homeostasis in sperm of boars. The experiment used adult boars of a large white breed, analogs in age, live weight and quality of sperm products. Experimental groups were fed copper citrate above the norm by 10% and 20%. It has been determined that feeding combined feed to boars with the addition of this compound in an amount of 10% above norm probably increases the weight of ejaculate by 12.5% (P<0.05), the sperm motility and survival by 6.5% (P<0.01) and 13.5% (P<0.001), respectively. Such changes in sperm occur against the background of an increase in SOD activity by 80.6% (P<0.05), a decrease in catalase by 43.5% (P<0.05), a slowing down of peroxidation processes — a decrease in diene conjugates and TBA-active compounds. The additional introduction to the diet of copper citrate by 20% more than normal increases the concentration of spermatozoa by 13.2% (P<0.01), the number of live spermatozoa by 20.7% (P<0,01), with a simultaneous decrease in their survival, due to the acceleration of peroxidation processes — an increase in the content of diene conjugates, TBA-active compounds and DAA and a decrease in reduced glutathione. It has been found out that the fertilizing ability of sperm significantly depended on the amount of fed microelement. Sows inseminated with sperm of boars receiving copper supplement in the diet by 10%, had higher fertility rates by 7.1%, multifertility by 3.6%, and a litter weight at weaning by 8.8%. The additional administration of copper citrate reduced the fertility of sperm by 20%, as the fertility rate of sows of III group was the lowest and was 7.7% and 14.3% lower compared to I and II groups. A similar trend occurred in terms of high fertility, a litter weight at birth and weaning. Therefore, the additional feeding of a small amount of copper has a positive effect on the functional activity of sperm and the processes of normal fertilization, growth and development of embryos and newborn piglets by optimizing the formation of prooxidant-antioxidant homeostasis.

Revealing peculiarities of the course of physiological and biochemical processes in the formation of parameters of ejaculate allows effective correlation of biological completeness of spermatozoids based on the use of chelate compounds of limiting microelements, particularly copper. The study was focused on determining changes in processes of spermatogenesis during correction of mineral nutrition. In the experiment, we used adult boars of the same age, live weight and quality of ejaculates. They consumed copper citrate during the 45 day experiment in doses higher than the norm by 10% (1.5 mg per 1 kg of combined feed) and 20% (3 mg per 1 kg of combined feed) compared with the control. We determined difference in the effects of different doses of copper citrate on the formation of parameters of ejaculates in sire boars. Addition of the mineral additive to the feed in the doses 10% exceeding the norm promoted increase in the parameters of functional activity of spermatozoids – mobility and survival – on day 45 of the intake, which occurred against the background of acceleration of peroxidation processes (increase in the concentration of thiobarbituric acid of active compounds) and activation of the system of antioxidant protection – increase in the activity of superoxide dismutase and decrease in the level of catalase in the sperm. At the same time, we observed increase in the morphometric parameters of spermatozoids – general length, width, length and volume of the head. On day 30, sire boars that had been consuming copper citrate in the amounts 20% above the norm were observed to have increase in concentration of spermatozoids, their mobility and survivability, though a decrease was seen in the morphometric parameters of the gametes. Further intake of this element caused increase in the amount of abnormal forms of spermatozoids. Under the action of this additive, we determined increase in the amount of metabolites of lipid peroxidation – conjugated dienes and thiobarbituric acids of active compounds, and also weakening of the system of antioxidative protection – decrease in the content of reduced glutathione and accumulation of dehydroascorbic acid. Thus, the intake of copper citrate in the amounts of 10% above the norm facilitated morpho-functional parameters of spermatozoids by activating the system of antioxidant protection. It would be promising to conduct further research to determine the effects of copper citrate on the processes of activation and capacitation of spermatozoids and fertilization of oocytes in in vivo and in vitro conditions.