Effect of experimental long-term exposure to low-dose zearalenone mycotoxicosis on selected morphometric parameters of the reproductive tract in sexually-immature gilts

The objective of this study was to determine the effect of long-term (48 d), per os animal administration of low zearalenone (ZEA) doses (50% and 100% NOAEL values) on the dynamics of changes in the morphometric parameters of the reproductive organs in sexually-immature gilts. The experiment involved 12 clinically-healthy gilts aged 2 months with initial body weight of ± 40 kg and a determined immune status. The animals were randomly divided into two experimental groups (El, n=4; E2, n=4) and a control group (C, n=4). Group El was administered per os 20 µg of ZEA/kg b.w. for 48 d, group E2 received per os 40 µg of ZEA/kg b.w. for 48 d, and group C was administered per os placebo for 48 d. The mycotoxin was administered daily per os animal in gelatin capsules before morning feeding. The animals were slaughtered at the end of the experiment. No significant morphometric changes were noted in the reproductive system of the gilts, except for an increase in the number of medium-sized ovarian follicles in group El. This suggests that ZEA at low concentrations may cause hormonal effects (hyperoestrogenism) but it does not exhibit xenobiotic activity.