Dehydroepiandrosterone and cortisol/dehydroepiandrosterone ratios in dairy cattle with postpartum metritis

Dehydroepiandrosterone (DHEA), a C19 steroid synthesized predominantly by the adrenal cortex, and its sulfated precursor (DHEAS) has antiglucocorticoid and immunoprotective properties. DHEA is important in modulating inflammatory responses; therefore, we hypothesized that DHEA concentrations might be altered in bovine postpartum metritis. DHEA, DHEAS, the cortisol/DHEA-ratio (C/D-ratio) and the DHEAS/DHEA ratio were determined in cows with and without clinical metritis subcategorized by the blood leukocyte numbers. Blood from the coccygeal vein of 37 pluriparous Holstein-Friesian cows was sampled 8.8 ± 0.9 days (mean ± SE) after calving. Based on clinical signs of metritis and leukocyte numbers (normal range 5-10 × 106/μl), cows were classified as healthy with leukocyte numbers in the reference range (leukocyte normal; LNH = 5954.17 ± 302.4/μl); suffering from metritis with normal leukocyte counts (LNM = 7422.22 ± 774.74/μl); or metritis with leukopenia (LLM = 3950 ± 284.31/μl P < 0.01). Cows with metritis had higher DHEA concentrations than healthy cows (P < 0.05). Notably, cows with both metritis and leukopenia displayed higher DHEA concentrations than cows with metritis and normal leukocyte numbers (DHEA LLM 8.15 ± 3.09 vs. LNM 4.09 ± 1.82 ng/ml, P < 0.05). Cows with metritis and leukopenia also had lower C/D-ratios than healthy cows. In conclusion, DHEA and the cortisol/DHEA-ratio could represent an anti-inflammatory signal during prolonged inflammation of the reproductive tract in dairy cattle and may be a biomarker or prognostic indicator for evaluating disease severity, as seen in serious chronic illnesses in other species.