Localisation of Estrogen Receptor Alpha and Progesterone Receptor B in Goat Ovaries During Breeding and Non-Breeding Season

The main objective of this study was to investigate the localisation of estrogen receptor alpha (ER-alpha) and progesterone receptor B (PR-B) by immunohistochemistry in goat ovaries during in- and out of breeding season. The ovaries obtained from goats slaughtered in breeding season (n=10) and non-breeding season (n=10) were used. From the same animals, blood samples were taken to determine the levels of serum steroid hormones (E-2, P-4). The ER-alpha and PR-B immunohistochemical distributions within the ovaries were determined by the ABC method. In breeding season, the ER-alpha was detected in the germinal epithelium and follicular granulosa cells. The PR-B was determined to concentrate on the corpus luteum (CL) cells. The same receptors were also found to be weak in the theca externa cells of preovulatory follicles. In non-breeding season, the ER-alpha germinal epithelium and smooth muscle cells of certain blood vessels showed a weak positive reaction. The PR-B was positively stained in the germinal epithelium and few stroma cells. It was suggested that the average steroid hormone profiles in breeding (E-2: 11.83 +/- 1.70 pg/mL, P-4: 10.08 +/- 1.58 ng/ml) and non-breeding season (E-2 2.33 +/- 0.85 pg/ml, P-4 0.21 +/- 0.04 ng/ml) correlated well with the localisation intensity of receptors in goat ovaries.