Dynamics of morphofunctional activity of blood lymphocytes of Stavropol breed sheep in postnatal ontogenesis and during pregnancy

The aim of the paper was to study the activity of nucleolar organizer zones of blood lymphocytes of Stavropol breed sheep in postnatal ontogenesis and during pregnancy. Blood smears for cytomorphology studies were painted with silver nitrate and subsequent additional coloring with azure and eosin. By measuring the parameters of the nucleus and parameters of the activity of nucleolar organizers (AgNORs), the changes in the morphofunctional state of the protein-synthesizing apparatus of blood lymphocytes in sheep of Stavropol breed in postnatal ontogenesis were evaluated. It was found that newborn lambs’ area of the nuclei of lymphocytes was 76.50 ± 2.30 µm2. By the age of three months, the area of lymphocyte nuclei in sheep significantly increased by 6.08% and amounted to 81.46 ± 2.45 µm2, and did not change significantly until the age of twelve months. The number of units of argentophilic nucleolar organizers in the nuclei of lymphocytes (AgNORs) is from 1 to 4. The average area of AgNORs in the nuclei of lymphocytes is in the range from 73.60 ± 2.45 up to 80.10 ± 2.41 µm2. In sheep of Stavropol breed on the 90th day of pregnancy, the area of the nucleus of lymphocytes was 68.70 ± 2.15 µm2. By 135 days of pregnancy, a significant decrease in the area of the nuclei of the lymphocytes by 14.66% was found. After childbirth, there was a slight decrease in the area of lymphocytes in sheep compared to the previous period of research. During pregnancy, sheep were found to have from 1 to 3 AgNORs with a total area from 0.70 ± 0.11 to 2.93 ± 0.43 µm2. On the basis of the conducted studies, it can be concluded that in postnatal ontogenesis and during pregnancy of sheep, the functional state of lymphocytes changes, this is manifested in changing the parameters of the area of their nuclei, the number and total area of AgNORs.