SUMMARY
This article describes the main reasons of hypovitaminosis in hens and the results of studying the effectiveness of vitamin–mineral premix and probiotics in prevention. The main causes of hypovitaminosis in egg–laying hens are alimentary factors, including the lack of retinol, tocopherol, cholecalciferol, ascorbic acid and inorganic phosphorus in the farm ration compared to the standard indicators. Based on the analysis of the experiment results, it was found that the use of complex of vitamins and minerals Vitaprem together with probiotics had a positive effect on the process of metabolism of vitamins and minerals in the body of egg–laying hens.