Effects of Dietary Contamination by Zearalenone and Its Metabolites on Serum Anti-Müllerian Hormone: Impact on the Reproductive Performance of Breeding Cows.

We investigated the effects of in vivo exposure to low zearalenone levels on the anti-Müllerian hormone endocrine levels and the reproductive performance of cattle. Urine and blood samples and reproductive records were collected from two Japanese Black breeding female cattle herds with dietary zearalenone contamination below the threshold levels (<1 ppm) at 30 days after calving. Urinary zearalenone, α-zearalenol and β-zearalenol concentrations were measured by chromatography-tandem mass spectrometry, and serum anti-Müllerian hormone concentrations were determined along with serum biochemical parameters. Urinary concentrations of α-zearalenol were significantly higher (p < 0.05) in cattle in Herd 1 than in cattle in Herd 2, reflecting the different amounts of zearalenone in the diet of the two herds. Although the number of 5-mm and 10-mm follicles of the herds and their fertility after artificial insemination were similar, the serum anti-Müllerian hormone concentrations in herds 1 and 2 were 438.9 ± 48.6 pg/ml and 618.9 ± 80.0 pg/ml, respectively, with a trend towards a significant difference (p = 0.053), which may indicate differences in the antral follicle populations between herds. Thus, zearalenone intake from dietary feed, even when below the threshold zearalenone contamination level permitted in Japan, may affect the ovarian antral follicle populations, but not the fertility, of post-partum cows.