Histological Study of Gonadogenesis in Potamopyrgus Antipodarum and Valvata Piscinalis

Abstract

This study focuses on gonad development in two freshwater gastropod prosobranch snail species (Potamopyrgus antipodarum and Valvata piscinalis). These biological models have been shown to be sensitive to various reprotoxic substances and are known to be relevant organisms for studying endocrine-disrupting substances. Therefore we took up a histological study of their anatomy and the gametogenesis of the two species in order to key into biological elements potentially useful for reprotoxic stress studies. Knowing that P. antipodarum is parthenogenetic, we studied all their gonadogenetic stages, taking caution to clearly describe the different oocyte developmental stages leading to the formation of the copulatory bursa, characterizing neighboring glands. As for V. piscinalis, a hermaphrodite species, all the spermatogenesis development stages were described This studied was carried out by observing the development of young P. antipodarum and V. picinalis, exposing them to the same experimental conditions for 6 months. Weekly samples were taken for biometric imaging and conventional histology photonics in order to determine the age and to validate the appearance of early gonadogenesis.