Data/hora: 01/06/2024 07:26:07

Provedor de dados: | 83
País: | Brazil
Título: | Ontogenetic development of tetra Astyanax lacustris (Characiformes: Characidae)
Autores: | Stevanato,Diego J.; Ostrensky,Antonio.
Data: | 2018-01-01
Ano: | 2018
Palavras-chave: | Astyanax lacustris; Larval morphometry; Notochord; Ontogeny; Swim bladder.
Resumo: | ABSTRACT Ontogenetic development of the tetra Astyanax lacustris was studied under laboratory conditions. Larvae obtained by induced reproduction were maintained individually in tissue-culture plates, at 25°C. Daily observations and morphometric measurements were performed. Larvae hatched with a total length (TL) of 3.02 ± 0.34 mm (average ± standard deviation) without pigmentation and 0.06 ± 0.02 mm³ of yolk reserves. The yolk-sac larval period lasted 26 h post-hatching (hph). During this period, eye pigmentation started, the digestive tract emerged, the anus opened, and the animals began to show steady movements. Inflation of the swimming bladder initiates the preflexion stage, which extended until 230 hph. During this stage, the transition from endogenous to exogenous feeding was observed, with the yolk reserve being completely absorbed after 74 hph (TL: 4.17 ± 0.36 mm). Up to 86 hph it was possible to observe the first food ingested within the digestive tract. This period was followed by the flexion stage, with the folding of the notochord tip and development of the caudal fin (11-13 days post-hatching). Finally, during the last larval developmental stage (postflexion), the segmentation of the fin rays was completed, and the emergence of scales was observed (TL: 5.97 ± 0.65 mm). The larval ontogenetic development of A. lacustris was completed after 22 post-hatching days (dph).
Tipo: | Info:eu-repo/semantics/article
Idioma: | Inglês
Identificador: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252018000200206
Editor: | Sociedade Brasileira de Ictiologia
Relação: | 10.1590/1982-0224-20170073
Formato: | text/html
Fonte: | Neotropical Ichthyology  v.16 n.2 2018
Fonte: | info:eu-repo/semantics/openAccess