Inflammatory cytokine and acute phase protein concentrations in the peripheral blood and uterine washings of cows with subclinical endometritis in the late postpartum period

The aim of the study was to evaluate the concentrations of proinflammatory cytokines: tumor necrosis factor (TNF-α) and interleukin-6 (IL-6), anti-inflammatory cytokine interleukin-10 (IL-10), and acute phase proteins (APPs)—haptoglobin (Hp) and serum amyloid A (SAA) in serum and uterine washings of cows with subclinical endometritis, and compare them to healthy animals. The study was performed on 24 cows on day 60 after delivery. The cows were divided into two groups based on the results of cytological tests: 12 cows with subclinical endometritis and 12 healthy cows. Experimental material consisted of blood serum and uterine washings. The levels of the following cytokines in the study material were determined with ELISA: TNF-α, IL-6, IL-10 and APPs - Hp and SAA. The results show that the levels of TNF-α (p < 0.01), IL-6, IL-10 as well as SAA and Hp were significantly higher in the serum of cows with subclinical endometritis compared to the controls (p < 0.001). Uterine washings had significantly higher levels of IL-6, IL-10, and Hp in the experimental cows compared to the controls (p < 0.001). The demonstrated differences in the concentration of cytokines and APP between cows with subclinical endometritis and healthy cows, in both the serum and uterine washings, may suggest the usefulness of these parameters in the diagnosis of subclinical endometritis in cows in the late postpartum period.