Effects of estrogenic and antiandrogenic compounds on the testis structure of the adult guppy (Poecilia reticulata)

Sexually mature male guppies (Poecilia reticulata) were exposed to 17β-estradiol, 4-tert-octylphenol, bisphenol A, flutamide, p,p′-DDE, or vinclozolin to determine the effects of these estrogenic or antiandrogenic substances on the testis structure. Flutamide, p,p′-DDE, 4-tert-octylphenol, and bisphenol A exposure caused similar effects. These included a reduced number of spermatogenetic cysts and an increased number of spermatozeugmata in the ducts. These effects are indicative of a blocked spermatogonial mitosis. 17β-Estradiol produced effects different from those of the other compounds studied. The effects were seen as an increased number of hypertrophied Sertoli cells/efferent duct cells. The mammalian antiandrogen vinclozolin had no observable effects on the testis structure when given in doses of 1, 10, or 100 μg/mg food.