Uterine hemodynamic patterns, oxidative stress, and chromoendoscopy in mares with endometritis

This study aimed to evaluate the use of Doppler ultrasound for determining alterations in uterine thickness and uterine arteries, use of chromohysteroscopy in evaluating endometritis with biopsies, and the impact of endometritis on oxidative and hormonal status. Twenty Arabian mares were divided into control and endometritis groups. Each underwent a physical examination, Doppler ultrasound, chromoendoscopy, and uterine biopsy. Blood samples from each animal were collected for hematologic, hormonal, and oxidative analysis. Results revealed a significant increase in estradiol, malondialdehyde (MDA), and nitric oxide metabolites (NOMs) associated with a significant decrease in progesterone and total antioxidant capacity (TAC) in the endometritis group. There was a significant difference in uterine thickness in the endometritis group. Uterine blood flow analyzed by color mode showed a significant increase in the endometritis group, while the spectral mode showed a significant increase in Doppler velocities and blood flow rate accompanied by a significant decrease in Doppler indices. The endometritis group showed ridged, bluish color in the endometrial wall, indicating hyperemia. Biopsy showed mononuclear inflammatory cells and edema in the endometrial interstitial tissue with sloughing of the epithelial lining. Conclusion: Endometritis in mares is associated with oxidative processes and presents with an increase in MDA and NOMs and a decrease in TAC. Doppler ultrasound improved endometritis diagnosis because it showed alterations in uterine vascularization. Chromoendoscopy improved the accuracy in taking biopsy samples because it allows the practitioner to select appropriate areas for biopsy to improve histopathological diagnostic outcomes. Therefore, this technique is worthy of further study in the field of veterinary equine reproduction. •Chromoendoscopy improved the accuracy in taking biopsy samples in endometritis.•Uterine blood flow elevated in endometritis mares.•Estradiol and malondialdehyde levels increased, while progesterone level decreased in endometritis group.