Changes of serum anti‐ M üllerian hormone in a mare with granulosa cell tumour following surgery and reinitiation of follicular activity

• Published in: Equine veterinary education Vol. 26; no. 9; pp. 481 - 484
• Main Authors: Gharagozlou, F., Youssefi, R., Akbarinejad, V., Masoudifard, M., Ashrafihelan, J.
• Format: Journal Article
• Language: English
• Published: 01-09-2014
• DOI: 10.1111/eve.12170
• EISSN: 2042-3292
• ISSN: 0957-7734

Anti‐Müllerian hormone (
AMH
) has been reported to be elevated in mares with granulosa cell tumour (
GCT
). An 8‐year‐old Thoroughbred mare was presented for not being observed in oestrus after the beginning of the breeding season. Rectal palpation and ultrasonography revealed enlargement and cystic appearance of the left ovary while the right ovary was small with an anoestrous‐like appearance. The
AMH
concentration was 694.9 ng/ml. Presumptively diagnosed with
GCT
, the mare was subjected to tumour removal. Histopathology confirmed
GCT
. To evaluate changes of
AMH
concentration following surgery, blood samples were collected immediately prior to surgery, and on Days 1, 2, 4, 8, 16 and 32 after surgery. Thereafter, blood samples were collected monthly and also at the time the mare was observed in oestrus (148 days after tumour removal). The
AMH
concentrations decreased over the first 2 months after surgery (from 721.2 ng/ml to 0.1 ng/ml). Subsequently,
AMH
concentration increased and peaked at the time of oestrus expression (0.7 ng/ml). The mare then became anoestrous, and
AMH
concentration decreased and reached 0.2 ng/ml, which was not significantly different from the mean concentration of
AMH
in normal anoestrous mares (n = 5; 0.26 ± 0.07 ng/ml). In conclusion, the present report implies the potential use of
AMH
for determination of the time of follicular resumption in mares after
GCT
removal.