TDK conference 2016

Non-pregnant, subfertile broodmares cause a significant expense in horse breeding, because of the increased veterinary outgoings and the additional charges of the favourable sire’s semen. There are numerous causes of decreased fertility in mares. Beyond the routine physical and sonographic examination, advanced techniques are available for diagnosing subfertility (microbiology, endometrial biopsy) in mares. For detecting inflammatory and degenerative changes of the endometrium, from the 1960s, histopathologic studies have been investigated the most reliable fixation method and the optimal time for the sampling, but the authors not always agree in these issues.

In this study, a total of 34 privately owned mares with at least 1 year infertility in their history have been evaluated. In 26 cases, samples were collected during estrus, and were fixated in 8% buffered formalin; in 8 cases, diestrous samples have been collected, and beside formalin, a Bouin-solution has also been used as a fixative. In those 8 cases, an additional microbiological sampling has also been made.

In most cases, the physical and sonographic examinations could not detect abnormalities in the mares’ genital tracts. During the analysis of the microbiology samples, aerobic as well as anaerobic microbial organisms could have been cultured. Histopathological investigation detected acute and chronic changes in the endometrial tissue, however, these findings were not always concordant with the history and the later conception rate (if this data is known).

According to our results, in case of infertility/subfertility of broodmares of high value, the use of advanced examination techniques is suggested in order to detect subclinical diseases; however, a single examination is not sufficiently enough to estimate the fertility of the broodmare.