Effect of ovariectomy on age and serum concentrations of Anti-Müllerian Hormone in mares

Author(s)

Renata Cristina Uliani

• Document type: Doctoral Thesis
• Press: Botucatu. 2016-12-06.
• Institution: Universidade Estadual Paulista (Unesp). Faculdade de Medicina Veterinária e Zootecnia. Botucatu
• Defense date: 2016-11-22
• Advisor: Marco Antonio Alvarenga

Abstract

Anti-Müllerian hormone (AMH) has been proposed as a reliable marker of ovarian reserve, estimating the expected remaining female reproductive life. Currently, in human assisted reproduction, AMH has been used to determine the treatment to be followed and lead to the expectation of the patient. In horses, little is known about the production of AMH and its clinical significance. Thus, the aim of this study was to describe the production of AMH lifelong of mares and evaluate its production after ovariectomy, aiming to relate AMH with ovarian follicular reserve. 2 experiments were performed. Experiment 1: 1058 Quarter Horse mares, from 1 day to 33 years old were sampled in order to relate AMH with the age of the mare. Experiment 2: 13 mares (6 young and 7 old) underwent two ovariectomy surgeries with a mean interval of 111 days. Blood samples for AMH levels were drawn immediately before surgery and daily for 15 days. In the second surgery, blood samples were collected immediately before surgery and 15 days after. AMH was measured by ELISA (Equine AMH ELISA; Ansh Labs, Webster, TX, USA). Non-parametric tests were used to compare the median AMH levels between different age categories and the mean in the pre and postoperative periods. Age was responsible for only 5% of the variability in AMH levels. The average production was maintained from birth to about 18 years, when started to fall slowly. The decrease is higher with approximately 23 years of age and reaches zero after 30 years. The production of AMH after unilateral ovariectomy shows an abrupt drop in the post-surgery period. After the interval between the first and second surgery, the mares showed a recovery in the production of serum AMH. In conclusion, AMH doesn’t have a correlation with age in mares. More works need to be carried out with the aim of linking AMH with ovarian follicular activity in mares. (AU)

• FAPESP's process: 14/13191-1 - Study of anti-Mullerian hormone in mares: relationship with age and expression of ovarian receptors
• Grantee: Renata Cristina Uliani
• Support Opportunities: Scholarships in Brazil - Doctorate