title: Structural and ultrastructural description of larval development in Zungaro jahu.
abstract: The Zungaro jahu is an important large catfish of the order Siluriformes that is in danger of extinction due to habitat destruction. Studies on its biology are scarce and the majority relates only to nutrition or parasitology. In order to provide greater information on its morphology and aid husbandry and larviculture studies, the aim of this study was to characterize larval development in Z. jahu from hatching to total yolk absorption. Samples were collected at pre-established times, processed, stained, and analyzed under stereomicroscopy, light microscopy, and scanning electron microscopy. Total yolk absorption was observed by 60 hours post-hatching (hph) at 28.75 ± 0.59°C. The newly hatched larvae showed slightly pigmented body, the outline of the digestive tract, evident eyes, and the first swimming movements. Mouth opening took place at 12 hph and the connection between the oral cavity and the rudimentary intestine was observed at 24 hph. Were analyzed the main larval organs and systems: digestive organs, heart, gill arches, sensory system, thyroid, kidney, and swim bladder. As the larvae grew, these organs became more mature and functional. The development of the sensory and feeding structures was observed at the start of larval development, and thus before depletion of endogenous energy reserves, the strategy for this species is to increase its chances of survival in the environment.
authors.affiliation: Fundação Amaral Carvalho,Jaú,São Paulo,Brazil.
authors.forename: Camila
authors.initials: C
authors.lastname: Marques
authors.affiliation: Universidade Federal de São Carlos,São Carlos,São Paulo,Brazil.
authors.forename: Francine
authors.initials: F
authors.lastname: Faustino
authors.affiliation: Fundação Amaral Carvalho,Jaú,São Paulo,Brazil.
authors.forename: Bruno
authors.initials: B
authors.lastname: Bertolucci
authors.affiliation: UNESP's Aquaculture Center (CAUNESP),Universidade Estadual Paulista,Campus Jaboticabal,São Paulo,Brazil.
authors.forename: Maria do Carmo Faria
authors.initials: MDCF
authors.lastname: Paes
authors.affiliation: UNESP's Aquaculture Center (CAUNESP),Universidade Estadual Paulista,Campus Jaboticabal,São Paulo,Brazil.
authors.forename: Fernanda Nogueira
authors.initials: FN
authors.lastname: Valentin
authors.affiliation: Centro de Aquicultura da UNESP - Departamento de Morfologia e Fisiologia Animal,Faculdade de Ciências Agrárias e Veterinárias (FCVA),Univesidade Estadual Paulista 'Julio de Mesquita Filho',Via de Acesso Professor Paulo Donato Castellani,S/N,Jaboticabal-SP,CEP 14884-900,Brazil.
authors.forename: Laura Satiko Okada
authors.initials: LSO
authors.lastname: Nakaghi
mesh_terms: D000818:Animals; D002397:Catfishes / Q000254:growth & development*; D004064:Digestive System / Q000254:growth & development / Q000648:ultrastructure*; D004625:Embryo, Nonmammalian / Q000166:cytology / Q000648:ultrastructure*; D007814:Larva / Q000254:growth & development / Q000648:ultrastructure*; D008855:Microscopy, Electron, Scanning / Q000379:methods*
keywords: Fish; Histology; Morphology; Ontogeny; Teleostei