An attempt to interpret fertility disturbances in mares

The owners of breeding mares often have a smaller percentage of foaling tha n they expect. This is often caused by some gynaecological disturbances whi ch reduce the reproductive potential of mares. Therefore, 30 (100%) mares w hich had not foaled in their previous breeding season were subjected to cli nical analysis. The mares underwent gynaecological examination before the b reeding season from January to March (external examination; rectal examinat ion; by palpation and sonography,vaginoscopy, uterus bacteriology, mycology , cytology and biopsy). The gynaecological examination allowed 26 (86.6%) mares to be diagnosed and treated accordingly. The mares were subsequently foaled from March to July and 21 (70%) of them became pregnant (pregnancy control to 150-th day). Gy naecological examination of 4 mares (13.3%) did not uncover the reasons for theor infertility. In the case of these mares the following factors should be taken into account: improper organisation of breeding season, hormonal disturbances connected with the immunological uterus status and some chromo somal defects. The article indicates various reasons for infertility: anato mical defects in external genital organs, endometritis, endometriosis, tumo r of uterus cervix, disturbances in uterus contraction and fluid accumulati on in uterus the absence of sexual activity in the breeding season. Diagnos is and treatment of fertility disturbances in mares should be carried out b ased on the results of precise gynaecological examination. In addition, the research indicated that the frequency of early embryonic death and miscarr iage correlate with the intensity of changes in the endometrium detected du ring cytological, microbiological, histological examinations.