The light microscopic investigation of the effects of in-ovo administered bisphenol A (BPA) on the development of testes

Abstract

The aim of this study was to determine the effects of BPA on testes development in chicken embryos. For this purpose, 310 fertile eggs of Isa Brown laying parent stock were divided into five groups as control, vehicle-control, 50, 100, and 250 µg/egg BPA. Test solutions were injected into the yolk before incubation. At the 13th, 18th and 21st days of incubation, the eggs were opened until six living male embryos were obtained from each group. Tissue samples were fixed in 10% buffered formalin (pH 7.4). After routine histological processes, tissue samples were embedded in paraffin. Six µm thickness sections were stained with the Crossmon’s trichrome method. All histological evaluation and histometrical measurements were performed on the left testes. On the 13th, 18th and 21st days of the incubation, the groups that were treated with BPA showed growth retardation in testicular tissues, fewer cell cords and poorly cellular organization. At 21 days of the incubation, there were a significant decrease in the mean diameter of the seminiferous tubule in all experimental groups compared to control groups (p<0.05). The increase in mean cortical thickness was observed in the BPA treated groups compared to the control groups (p<0.05). The mean testes surface area was higher at 50 µg/egg and 100µg/egg BPA treated groups compared to the control groups and at 250 µg/egg BPA administered group (p<0.05). In 50 and 100 µg/egg BPA treated chicken embryos, BPA triggered ovo-testis formation by characterizing thickened cortex containing oocytelike cell clusters whereas BPA had toxic effects at 250 μg/egg. It was concluded that BPA can induce both estrogen-like and toxic effects in the developing testes of chicken embryos in a dose-dependent manner