Medycyna Wet. 62 (2), 207-211, 2006
Kusy R., Wawron W.
Sexual activity in Arabian mares with endometriosis in the winter season
Illnesses of the genital tracts, often complicated with inflammation and degenerative processes in the endometrium and disturbances in ovarian function, reduce fertility in mares. The aim of the study was to estimate ovarian activity and assess intranuclear estrogen receptors in the endometrium of mares suffering from endometriosis. The study was performed prior to the breeding season (December.January) on 13 Arabian mares suffering from average to highly advanced degenerative changes in the endometrium. Ovarian ultrasonography and estimations of progesterone concentration in serum were performed three times over a 2 week period (examinations: I, II, III). Segments of endometrium were collected twice (at follicle sizes < 20 mm and > 25 mm) by biopsy and the quantity of intranuclear estrogen receptors were estimated in each layer of the endometrium. An ovarian cycle culminating with ovulation occurred in most of the mares over a period of 29 days (8 animals, 62%). The remaining 5 animals (38%) displayed: atresia of the dominant follicle (2 mares), anovulatory hemorrhagic follicles (2 mares), and persistent corpus luteum (1 mare). The average concentration of progesterone serum in two examinations (I and III) clearly exceeded the value of 1 ng/ml (p ≤ 0, 05 between I and II examinations). Stronger expressions and a greater score of immunoreactive estrogen receptors in each layer of the endometrium were noted when large follicles (p ≤ 0, 01) were found on the ovaries.
Keywords: Arabian mares, endometriosis