Cystic endometrial hyperplasia in dairy goats: morphological changes and expressions of estrogen receptor-α and...

Cystic endometrial hyperplasia (CEH), often associated with hydrometra or mucometra, is a serious condition of subfertility and infertility in dairy goats, severely affecting herd productivity. Although there are many clinical reports of hydrometra in goats, research specifically addressing the molecular pathogenesis of CEH in this species remains notably limited. The objective of this study was to describe the morphological alterations in the endometrium of goats with CHE and to evaluate the immunohistochemical expression patterns of estrogen (ER-α) and progesterone receptor (PR) in the uterine wall by comparing them with those of healthy control goats. Gross pathological examination showed bilateral uterine distension, with both uterine horns symmetrically distended. Histological examination revealed extensive cystic dilatation of the endometrial glands. Immunoreactivity was objectively quantified using digital image analysis (H-score). The most significant molecular finding was an overexpression of both PR and ER-α in the affected group. Specifically, PR H-scores were significantly higher in the surface epithelium, stromal cells, and normal glands of affected goats (p = 0.0043). Furthermore, digital quantification revealed a significant up-regulation of ER-α in cystic glands (p = 0.0010) compared to control tissues. (p = 0.0043). These results suggest that CEH in dairy goats is associated with a localized hormonal dysregulation involving a concomitant increase in steroid receptor expression. These findings contribute to a better understanding of the complex hormonal environment involved in uterine diseases of small ruminants.