108 A preliminary investigation of anti-Müllerian hormone as a biomarker for fertility in mares

Abstract

Anti-Müllerian hormone (AMH) has been indicated as a potential biomarker for fertility in other livestock species, such as cattle and sheep, particularly with regard to advanced reproductive technologies. The objective of this study was to identify potential correlations between AMH concentrations and success rates (yield) in mares presented for embryo-flushing and oocyte aspiration procedures. All procedures were performed in the same facility, by the same veterinarians, utilizing standard techniques. Blood samples were collected just before embryo-flushing (EF; n = 172) or oocyte aspiration (OA; n = 28), processed to harvest serum, and stored at −18°C for later analysis of AMH concentrations using ELISA test kits. Blood samples were collected before the administration of any sedation or other routine procedural medications. Correlations between AMH, yield, and age were analyzed for EF and OA separately, as well as pooled (PD; n = 200). There was a negative correlation ( P = 0.03) between AMH and age in OA mares, as well as a trend ( P = 0.07) for a negative correlation between AMH and age in PD mares, whereas no correlation ( P > 0.10) between the 2 was identified in EF mares. Among the EF mares, a negative correlation ( P = 0.03) between yield and age was identified, but not in OA or PD. Additional analysis of PD revealed that significantly greater ( P = 0.04) concentrations of AMH were found in mares where the procedure yielded 2 or more oocytes or embryos compared with procedures that yielded only one oocyte or embryo. There was no difference ( P = 0.15) in AMH concentrations between PD mares that yielded one or more oocytes or embryos compared with PD mares in which the procedure was unsuccessful in retrieving an oocyte or embryo. Our results regarding the negative correlation between AMH and age in EF mares agrees with previous literature. The greater AMH concentrations observed in mares which yielded 2 or more oocytes or embryos compared with mares which only yielded one oocyte or embryo suggests that AMH may have potential as a biomarker for fertility in mares, particularly with regard to advanced reproductive technologies; however, further research is needed.