Changes in white blood cells in sheep blood during selenium supplementation

The aim of the experiment was to evaluate the impact of selenium supplementation on white blood cell parameters in the blood of ewes. The total white blood cell (WBC) and differentiation of leukocytes in blood smear were detected by a microscopic analysis, and the CD4(+) and CD8(+) subsets were detected by flow cytometry. A decrease in the count of WBC was recorded during pregnancy; it was statistically significant only in the group supplemented with organic selenium. In the postpartal period there was a statistically significant increase in the percentages of CD4(+) and CD8(+) subsets but differences between the groups were not statistically significant. The results of the experiment documented that the supplementation of different forms of selenium did not markedly influence the dynamics of blood parameters in non-pregnant, pregnant and lactating ewes if the intake of vitamins and other essential microelements was adequate.