Histopathologic findings in uteri and ovaries collected from clinically healthy dogs at elective ovariohysterectomy: a cross-sectional study

Opinions on ovariohysterectomy (OHE) of bitches vary depending on region and country. In this descriptive, prospective cross-sectional study, uterine tracts and ovaries exhibiting gross pathologic findings (n = 76) were collected post-surgery from a reference population of 3,600 bitches (2.11% incidence) that underwent elective OHE during September to November 2013 and evaluated by histopathology examination. Data were evaluated by using descriptive statistics and chi-squared tests. Bitches were of crossbred background with average age 5 years (range 0.6–8.0 years) and most were nulliparous (69.7%) with no anamnesis of reproductive diseases (81.6%). Frequencies of proestrus, estrus, and diestrus were 42.1%, 6.6%, and 19.7%, respectively. The presence of mammary gland masses (5.3%) significantly correlated with histopathologic findings in ovaries and age of the bitch (p < 0.05). Predominant uterine histopathologies included cystic endometrial hyperplasia, periglandular fibrosis, lymphoplasmocytary endometritis, and adenomyosis (19.7%, 14.5%, 4.0%, and 2.6%, respectively). In ovaries, hyperplasia of rete ovarii, follicular cysts, oophoritis, adenoma of the rete ovarii, cysts of superficial structures, and granulosa cell tumors (10.5%, 10.5%, 7.9%, 4.0%, 2.6%, and 2.6%, respectively) were observed. The results reveal the presence of subclinical pathologies in healthy bitches, suggesting that OHE at an early age is beneficial for prevention of reproductive pathologies.