Histopathological examination of ovaries in bitches after experimental zearalenone mycotoxicosis

The present study deals with the influence of experimental ZEA mycotoxicosis on histopathological lesions in ovaries of bitches, which were administered zearalenone per os during anestrus phase for one hundred days. The experiment was performed on 9 sexually mature, clinically healthy bitches. The animals assigned into two experimental groups received zearalenone per os at two doses, 25 microg/kg b.w. and 50 microg/kg b.w., respectively: the bitches from control group received placebo per os. On the last day of zearalenone intoxication, the bitches were ovariohystorectomized. Histopathology and immunohistochemistry were performed. The study revealed that zearalenone and its metabolites caused profound regressive lesions: granular cells degeneration and atrophy. Numerous edemas and blood extravasations were also found. The intensity of these changes was significantly dose dependent. Furthermore, in ovarian cells and tissues of both experimental groups, no reaction for PCNA antigen was observed. In conclusion, zearalenone and its metabolites exerts unfavorable effects on the morphology of ovaries in bitches.