Embryonic development and larval growth of Brycon nattereri Günther, 1864 (Characidae) and its implications for captive rearing

Abstract

The aim of this study was to describe, for the first time, the embryogenesis and larval growth of the Paraitinga Brycon nattereri Günther, 1864 reared in captivity. After artificial fertilization, eggs were incubated at constant temperature (~19°C) and collected every 15 min during the first 3 h and then every 3 h until hatching. Five larvae were collected daily over 15 days for evaluation of the length, yolk sac volume and specific growth rate. The following stages of embryonic development were identified: zygote, cleavage, gastrula, segmentation and larval. The hatching occurred after 50-54 h, with larvae poorly developed and fully depigmented, devoid of mouth and swimming capacity, presenting 6.32 mm total length and 3.64 mm3 yolk sac volume. The mouth opening was observed between days 3-4 after hatching. The yolk sac absorption was slow during the first 3 days, increasing sharply after this period, being completed on the day 11. During this period there was a decrease in the larval growth rate. After yolk sac absorption, an increase in the growth rate was observed that coincided with the start of exogenous feeding. Cannibalism was not observed during the 15 days of evaluation. The initial development of B. nattereri was slow and poorly developed larvae in relation to other Brycon species, certainly due to the lower temperature required for egg incubation and larval rearing. Other studies are needed in order to develop techniques to improve the methods of incubating eggs and feeding larvae.

Embryogenesis and larval development of migratory matrinchãBrycon orthotaeniaGünther 1864 (Characiformes: Bryconidae)

“…Larval development of pirapitinga is a slower process. The Flexion stage was observed only on 14th DPH, as reported by Maria et al (2017). This difference can be attributed to the occurrence of the species in headwater regions where the waters are cold.…”

“…Therefore, in three species of the same genus, blastopore closure with yolk sac formation occurs six HPF in matrinchã and 6.5 HPF in pirapitanga B. orbignyanus (Valenciennes, 1850) at similar temperatures (Reynalte-Tataje, Zaniboni-Filho, & Esquivel, 2004). In pirapitinga, the yolk sac was formed 26 HPF at 19ºC (Maria et al, 2017), which compared to the other two species shows the degree to which temperature influences larval development.…”

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

“…In the study by Park et al (), the consumption of yolk sac and mouth opening were reported on the 3rd day after the hatching. Similarly, the mouth–anus opening and the consumption of the yolk sac were reported to occur on the 3th‐4th days after the hatching for some Characin species such as Paraitinga ( Brycon nattereri ) (Maria et al, ), Brycon orthotaenia (Gomes et al, ) and black skirt tetra ( Gymnocorymbus ternetzi ; Çelik et al, ). On the other hand, for Buenos Aires tetra ( Hyphessobrycon anisitsi ; Park et al, ), the mouth–anus opening and the consumption of the yolk sac may occur on the 7th day.…”

“…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 ). As can be seen, the eggs of the tetra species belonging to the Characidae family are in these sizes.…”

“…Knowledge on the larval development stages of fish is important, mainly for the determination of the moment of the yolk‐sac absorption and mouth opening, indicators of the need for exogenous feeding (Maria et al, ). In serpae tetra, the yolk sac was absorbed within 3–4 days and the larvae started to feed exogenously before the complete absorption of the yolk sac.…”