Cytometric Analysis of Surface Molecules of Leucocytes and Phagocytic Activity of Granulocytes and Monocytes/Macrophages in Cows with Pyometra

Pyometra is a serious problem in dairy cow herds, causing large economic losses due to infertility. The development of pyometra depends mainly on the immunological status of the cow. The aim of the study was a comparative evaluation of selected indicators involving non‐specific and specific immunity in cows with pyometra and in cows without inflammation of the uterus. The study was performed in 20 cows, which were divided into two groups: pyometra group and healthy group, each comprising 10 cows, based on the results of cytological and ultrasonographic tests. A flow cytometric analysis was performed for the surface molecules CD4, CD8, CD14, CD21, CD25 and CD4⁺CD25⁺ on leucocytes, and the phagocytic activity was determined from granulocytes and monocytes/macrophages in the peripheral blood and uterine washings, respectively. It was demonstrated that the percentage of phagocytic granulocytes and monocytes/macrophages in both the peripheral blood and uterine washings was significantly lower in cows with pyometra compared with the healthy group (p < 0.001). Significantly (p ≤ 0.001) lower percentage of CD4⁺, CD14⁺, CD25⁺ and CD4⁺CD25⁺ phenotype leucocytes was also observed in the peripheral blood of cows from the pyometra group, along with a significantly higher (p < 0.001) percentage of CD8⁺ and CD21⁺ lymphocytes as compared to the healthy group. The results of work indicate that disfunction of cell immunity coexisting with pyometra may be caused by a bacterial infection and the presence of blocking agents (IL‐10), released by the increasing number of CD8⁺ lymphocytes what leads to the advanced inflammation of uterus.