Всероссийский научно-исследовательский институт физиологии, биохимии и питания животных – филиал Федерального государственного бюджетного научного учреждения «Федеральный научный центр животноводства – ВИЖ имени академика Л.К. Эрнста»
ABSTRACT. The processes of animal fertilization and fetal development can largely depend on the interaction of immune cells with the structures of the reproductive organs. The article summarizes the results of a study of the distribution of white blood cells in cows (n = 21) in infertile (n = 45) and normal (n = 38) sexual cycles. It is shown that the total number of leukocytes in blood of cows in a normal cycle with subsequent fruitful insemination, generally increased (P<0.001) against the background of increased number of lymphocytes (P<0.01), decrease in segmented neutrophils (P<0.05), increased ratio of lymphocytes to neutrophils (P<0.01) and marked decrease of hematocrit (P<0.01) in comparison with animals in fruitless cycles. Significant changes in the ratio of functionally specialized white blood cells (lymphocytes and neutrophils) in cows during the resumption of full cycles can contribute to the creation of conditions necessary for fertilization. For the white blood of animals in normal cycles for 3-6 days before fertilization, the manifestation of short-term lymphocytosis, the presence of a minimum number of segmentonuclear neutrophils and the maximum values of the ratio of lymphocytes to neutrophils are characteristic. The maximum values of the ratio of the number of lymphocytes to neutrophils in the blood of cows in the first months after calving can be used as one of the prognostic markers of increased efficiency of their fertilization during this period.