Brycon gouldingi(Teleostei, Characidae): aspects of the embryonic development in a new fish species with aquaculture potential

Abstract

SummaryBrycon gouldingi is an endemic species from Tocantins-Araguaia basin, used as a food source by riverine communities and relevant to aquaculture. Information about the initial morphology of B. gouldingi, a recently described species, is absent. In the present study, we analysed the fertilization and the embryonic development of this species based on light and scanning electron microscopy. After collection of adult specimens in Mortes River -Mato Grosso, Brazil, adaptation to captivity and induced spawning at Buriti Fishculture, Nova Mutum -Mato Grosso, Brazil, in December 2007 and January 2008, samples were collected at pre-defined periods from egg extrusion up to larval hatching, which occurred at 13.9 ± 0.06 h post-fertilization (hpf) in average. At the moment of extrusion, the eggs were slightly ovoid bearing a single micropyle per oocyte with a funnel-shaped micropyle canal and vestibule covered with longitudinal folds, typical of the genus Brycon. The embryonic development of B. gouldingi was characterized by six stages with distinct features: zygote (from fertilization up to formation of egg-cell); cleavage (cell divisions resulting in blastomeres, including the morula phase); blastula (several embryonic cells in a cup shape, without distinction of cell boundaries); gastrula (cell movement); histogenesis/organogenesis (formation of tissues and organs); and hatching (larval chorion rupture). Right after hatching, the larvae presented neither swimming abilities nor visual accuracy, and the digestive trait was undifferentiated. The present study is the first report on biological features of embryogenesis in B. gouldingi, providing relevant information to several approaches, mainly related to taxonomy, ecology, conservation and captive rearing of this new Brycon species.

Embryonic and larval development of serpae tetra Hyphessobrycon eques (Steindachner, 1882)

“…In conclusion, morphological and histological findings indicate that embryonic and larval development stages of serpae tetra are the same as other characins (dos Anjos & dos Anjos, ; Çelik et al, ; Faustino et al, ; Pan, Zhan, & Gong, ; Romagosa, Narahara, & Fenerich‐Verani, ). Fertilized eggs of serpae tetra are spherical, transparent, demersal and adhesive.…”

“…The diameter of the eggs of Hyphessobrycon anisitsi , a species close to serpae tetra, was reported to be close to these species (average 0.74 ± 0.07 mm; in the range of 0.63–0.91 mm; Park, Han, & Han, ). Species close to serpae tetra such as Astyanax altiparanae (dos Santos et al, ), Brycon gouldingi (Faustino, Nakaghi, & Neumann, 2011), Gymnocharacinus bergi (Cussac & Ortubay, ), Gymnocorymbus ternetzi (Çelik, Çelik, Cirik, Gürkan, & Hayretdağ, ), Hydrocynus vittatus (Steyn, Gagiano, Deacon, & Preez, ) and Paracheirodon innesi (Vilasrao, ) are known to have eggs with a diameter in the range of 0.65–1.5 mm (Table ). On the other hand, tetra species such as Brycon nattereri (Maria, Ninhaus‐Silveira, Orfão, & Viveiros, ) and Brycon orthotaenia (Gomes, Sato, Rizzo, & Bazzoli, ) are reported to have eggs with a diameter between 1.5 and 3.09 mm (Table ).…”

TET2‐Mediated Spatiotemporal Changes of 5‐Hydroxymethylcytosine During Organogenesis in the Late Mouse Fetus

“…The methylation state of DNA changes during development, which is important in understanding how epigenetic mechanisms that drive tissue specification and organ functionality (Song et al, 2009;Ruzov et al, 2011;Faustino et al, 2011). However, systematic and detailed reports on DNA demethylation remain scarce during the various developmental stages.…”

Desenvolvimento larval de Brycon hilarii (Characiformes, Characidae)

“…Dentre as espécies de Brycon, B. cephalus (Günther, 1869) (lOPes et al, 1995;rOmaGOsa et al, 2001), B. insignis (andrade-Talmelli et al, 2001), B. guatemalensis (Regan, 1908) (arias, 2006), B. orbignyanus reynalTe-TaTaje et al, 2004;COrreia et al, 2010), B. gouldingi Lima, 2004(FausTinO et al, 2010 e B. orthotaenia Günther, 1864(GOmes et al, 2011 foram descritas considerando pelo menos parte do seu desenvolvimento inicial, porém, para B. hilarii, esse estudo é inexistente. Assim, considerando a relevância ecológica, pesqueira e zootécnica desta espécie e a importância de caracterizar e reconhecer suas fases larvais, este estudo tem como objetivos (i) descrever morfologicamente os estágios larvais de B. hilarii utilizando caracteres morfométricos e merísticos e (ii) verificar possíveis mudanças de taxas de crescimento ao longo do desenvolvimento dos estágios larvais por meio da análise das relações entre caracteres morfológicos, utilizando modelos analíticos de regressão.…”