Impact of anti-androgenic substances on gametogenesis of the rotifer Brachionus calyciflorus

Several studies have shown that pollutants with anti-androgenic activity have an impact on the sexual reproduction of the rotifer Brachionus calyciflorus (Joaquim-Justo et al., submit; Preston et al., 2001). The effects observed are compatible with the phenomenon of endocrine disruption. Fenitrothion, a non-steroidal anti-androgen induces a decrease in fertilization rate following exposure below or equal to 0,5 mg L-1.. The steroidal anti-androgen, cyproterone acetate increases number of cysts in population exposed to concentrations below or equal to 0,5 mg L-1. Cross mating experiments showed that effects of fenitrothion are due to an impact on males exclusively, while effects of cyproterone acetate exposition are due to an impact on females exclusively. In this study, we investigated the impact of fenitrothion on spermatogenesis and observed a decrease in the spermatozoa production and mobility with concentrations down to 0,5 mg L-1. We report a detailed description of the morphology of the male reproductive apparatus in B. calyciflorus based on optic, transmission electron and scanning electron microscopy in controls and exposed individuals.