3rd year large animal ECVS Resident Koret School of veterinary medicine Rishon LeZiyon, Israel
Ninety-One Ovariectomies for Granulosa Cell Tumor: Breeding Performance of the Mares and Histopathological Features of the Ovaries. Haddad R1, Anbari A1, Brenner O2, Sutton GA1, Kelmer G1. 1Koret School of Veterinary Medicine, Rishon LeZion, Israel; 2The Weizmann Institute of Science, Department of Veterinary Resources, Rehovot, Israel.
Granulosa Cell Tumor (GCT) is the most common ovarian neoplasia in mares. Reports describing breeding performance post ovariectomy are scares. The purpose of this study was to describe the breeding performances, histopathology features, and owners’ satisfaction for mares undergoing ovariectomy due to suspected GCT. Medical records were retrospectively collected. Inclusion criteria were mares undergoing ovariectomy due to suspected GCT between 2009 and 2020. Postsurgical fertility parameters were obtained and compared with a control group. Comparison was done by T-test or by Mann-Whitney Signed-Rank Test. Owners’ satisfaction was graded on a 1–5 scale. Histopathology findings were recorded. Significance was set as P < 0.05. The GCT group included 91 mares, consisted mainly Arabian mares with a mean age of 7.8 years. Breeding performance were not significantly different between groups; 86% mares had normal estrus cycles post ovariectomy (P = 0.28), Mean number of breeding attempts was 1.21 (P = 0.06) among the normally cycling mares post ovariectomy and 89.7% of them carried a foal to term. Mean score for owners’ satisfaction from surgical treatment was 4.6. Histopathology showed typical GCT characteristics but also revealed an undescribed feature; vacuoles with amphophilic liquid. Inability to conceive is the most common indication for ovariectomy. This study was the first to show normal breeding performances in large number of mares post-ovariectomy due to GCT. Analysis of the histological reports revealed a new GCT characteristic, vacuoles of amphophilic liquid. The main limitation of the study was the retrospective nature of it.