Ovary maturation stages and oocyte features in three species of the neotropical fish Hemiodus (Müller, 1842)

Abstract

Macro- and microscopic ovarian features of Hemiodus microlepis, H. ternetzi and H. unimaculatus were analyzed. Based on these features we proposed an ovarian maturation scale. The nine stages of the preliminary macroscopic fieldwork scale were reduced to five after microscopic analysis of ovaries. The microscopic analysis indicated a group-synchronous oocyte development common to the three species that were characterized as iteroparous synchronous spawners with a total spawning type. The remarkable thickness of the zona radiata layer and the large size of vitellogenic oocytes of Hemiodus ternetzi distinguished this species from the others.<br>Características macro- e microscópicas dos ovários de Hemiodus microlepis, H. ternetzi e H. unimaculatus foram analisadas. Com base nestas características foi proposta uma escala de maturação. Após a análise microscópica dos ovários, a escala macroscópica preliminar de nove estádios, utilizada em campo, foi reduzida a cinco. A análise microscópica indicou que o desenvolvimento grupo-sincrônico dos ovócitos foi comum às três espécies, caracterizadas como iteróparas de desova total. A notável espessura da zona pelúcida e o maior tamanho dos ovócitos vitelogênicos de Hemiodus ternetzi diferenciaram esta espécie das demais

Analyses of the development and glycoproteins present in the ovarian follicles of Poecilia vivipara (Cyprinodontiformes, Poeciliidae)

“…To describe these stages and macroscopically classify the ovarian development of P. vivipara we used the ovarian parameters described by Brandão et al (2003) and Chellappa et al (2005).…”

“…Several studies have been carried out aiming at understanding vitellogenesis and the reproductive biology of fish with external fertilization (Brandão et al 2003, Cognato & Fialho 2006. By contrast, oogenesis and the initial development of species with internal fertilization have not been sufficiently investigated.…”

Short-term changes in energy allocation by Hemiodontidae fish after the construction of a large reservoir (Lajeado Dam, Tocantins River)

“…After the formation of Lajeado Reservoir, Tocantins River, we recorded significant variation in some ecological traits of Hemiodontidae fish, especially body condition migration, reproduce seasonally during the rainy period and present total spawning type (Brandão et al, 2003;Medeiros et al, 2009;Neuberger et al, 2009). Species with such life history traits, what include many South American fish species, respond to specific environmental triggers (proximal factors) that stimulate the reproductive cycle -including migration, gonadal maturation and spawning (Vazzoler, 1996;Agostinho et al, 2004;Bailly et al, 2008).…”

Ovary maturatıon stages and histological investigation of ovary of the Zebrafish (Danio rerio)

“…In this study, the vitellin membrane began to develop at the vitellogenic growth stage. In another study the macro-and microscopic ovary features of Hemiodus microlepis, H. ternetzi and H. unimaculatus were analyzed by Brandao et al (2003). The microscopic analysis indicated a groupsynchronous oocyte development, common to the three species that were characterized as iteroparous synchronous spawners with a total spawning.…”