Epigenetic Disruption Analysis Of Zearalenol On Different Stages Of In-Vitro Culture Of Parthenogenetically Activated Bovine Embryos

As a preformed form on plant tissues being consumed by the animals or during the process of biotransformation, zearalenone is converted into many intermediate compounds including alpha and beta zearalenol, which may be toxigenic to the oocyte and subsequent embryo development stages. In this study, we observed in-vitro effects of 3 mu M, 30 mu M alpha and 3 mu M, 30 mu M beta zearalenol addition compared to the negative control group on the consecutive stages of bovine oocytes in the in-vitro maturation (IVM) media along with proceeding ill effects on parthenogenetically activated bovine embryos, in two steps defined in-vitro culture (IVC) media. Developmental competence of embryos was accessed by observing cleavage percentage, subsequent blastocyst formation percentage, and counting of nuclei of blastomeres in the individual blastocysts after Hoechst staining. With the increasing doses of relevant mycotoxins, we observed a decreasing trend of embryo cleavage with a significant difference (<0.05) among control to 30 mu M alpha and 30 mu M beta zearalenol groups. Blastocyst formation rate showed significant decrease in all mycotoxin added treatment groups compared with the control while the cell numbers of individual blastocyst were only reduced in 30 mu M beta zearalenol group compared to the control group (P<0.05). All these results indicate that beta zearalenol causes more genetic disruption to the subsequent stages of bovine zygotes as compared to the alpha zearalenol at the same concentration.