Alterations in the Vaginal Vascular Perfusion, Chromoendoscopy and Oxidative Stress in Mares With Vaginitis and Endometritis

This study aimed to demonstrate the vaginal tissue alterations via vaginal biopsy and hemodynamic alterations by introducing chromoendoscopy to analyse the effect of equine vaginitis on the oxidative and hormonal profile. Mares were divided into normal mares (N = 10) and affected mares (N = 10). Animals were subjected to Doppler ultrasonographic evaluation, endoscopic examination, oxidative stress was estimated, and biopsy samples were taken for histopathology and immunohistochemistry. Uterine body (UB) thickness (mm), circumference (mm) and area (mm²) elevated significantly in infected mares. Vaginal vascularization area elevated in the infected animals. The pattern was determined using pulsed wave Doppler. Both Doppler indices and systolic velocity declined significantly in both arteries (pudendal artery [vestibular B] and vaginal artery blood flow) in the infected group. Estradiol, insulin-like growth factor (IGF-1) and nitric oxide metabolites (NOMs) were significantly affected by the infection in mares. A significant increase in malondialdehyde (MDA) associated with a significant decrease in total antioxidant capacity (TAC) was observed in the vaginal fluid of affected animals. Chromoendoscopic examination revealed hypervisible inflamed os-cervix and vaginal wall. After methylene blue (MB) addition, there was bluish discolouration of the os-cervix, faint and deep bluish discolouration of the vaginal mucosa. The vaginitis group had a corrugated deep bluish colour in the mucosa. The expression of NF-κβ P65 was not observed in control; however, it was expressed in the mononuclear cells infiltrating the submucosa of the vagina of the affected animal. In conclusion, Equine vaginitis is associated with decline in both Doppler indices with elevation of MDA and a declination of TAC, in addition to hyper-visible inflamed os-cervix and vaginal wall by endoscopy and expression of NF-κβ P65.