Effects of dietary zearalenone intake on oocyte quality for in vitro embryo production and on serum anti-Müllerian hormone and inflammatory marker levels, following ovum pick-up in Japanese Black donor cows

In Japanese Black (JB) cattle, the number and percentage of transferable in vitro fertilization (IVF) embryos after oocyte collection are essential for the economic success of embryo production. Anti-Müllerian hormone (AMH) is a useful predictive marker for the number of cumulus-oophorus complexes (COCs) obtained through transvaginal oocyte retrieval. We aimed to examine the relationship of AMH levels, serum amyloid A (SAA) levels, and albumin/globulin (A/G) ratios, which are inflammatory markers, and urinary zearalenone (ZEN) levels, which reflect dietary ZEN intake, with the number and quality of oocytes recovered after ovum pickup (OPU) in JB donor cows as well as the number and rate of transferable IVF embryos. Oocytes obtained after OPU were fertilized in vitro. Additionally, blood and urine samples were collected at the time of OPU to assess serum AMH and SAA levels as well as urinary ZEN levels. The number of recovered oocytes (R = 0.745, P = 0.000) and transferable embryos was positively correlated with AMH levels (R = 0.704, P = 0.000) and negatively correlated with gamma-globulin levels. Furthermore, the percentage of transferable embryos per total number of embryos was positively correlated with urinary ZEN levels (P = 0.027). In conclusion, AMH levels can inform the selection of JB donor cows for OPU. Moreover, substandard ZEN contamination of dietary feed may not affect embryo production following OPU; instead, it may result in an increased number of transferable embryos, and in turn facilitate oocyte nuclear and cytoplasmic maturation during follicle development.