title: Embryonic development in Zungaro jahu.
abstract: The aim of this study was to characterize the embryonic development of Zungaro jahu, a fresh water teleostei commonly known as 'jaú'. Samples were collected at pre-determined times from oocyte release to larval hatching and analysed under light microscopy, transmission electron microscopy and scanning electron microscopy. At the first collection times, the oocytes and eggs were spherical and yellowish, with an evident micropyle. Embryo development took place at 29.4 ± 1.5°C and was divided into seven stages: zygote, cleavage, morula, blastula, gastrula, organogenesis, and hatching. The differentiation of the animal and vegetative poles occured during the zygote stage, at 10 min post-fertilization (mpf), leading to the development of the egg cell at 15 mpf. From 20 to 75 mpf, successive cleavages resulted in the formation of 2, 4, 8, 16, 32 and 64 blastomeres. The morula stage was observed between 90 and 105 mpf, and the blastula and gastrula stage at 120 and 180 mpf; respectively. The end of the gastrula stage was characterized by the presence of the yolk plug at 360 mpf. Organogenesis followed, with differentiation of the cephalic and caudal regions, elongation of the embryo by the cephalo-caudal axis, and somitogenesis. Hatching occurred at 780 mpf, with mean larval total length of 3.79 ± 0.11 mm.
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 Centre (CAUNESP),Universidade Estadual Paulista,Campus Jaboticabal,São Paulo,Brazil.
authors.forename: Maria do Carmo Faria
authors.initials: MD
authors.lastname: Paes
authors.affiliation: UNESP's Aquaculture Centre (CAUNESP),Universidade Estadual Paulista,Campus Jaboticabal,São Paulo,Brazil.
authors.forename: Regiane Cristina da
authors.initials: RC
authors.lastname: Silva
authors.affiliation: Departamento de Morfologia e Fisiologia Animal,Faculdade de Ciencias Agrarias e Veterinarias (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: LS
authors.lastname: Nakaghi
mesh_terms: D000818:Animals; D036703:Blastula / Q000166:cytology; D002397:Catfishes / Q000196:embryology*; D004625:Embryo, Nonmammalian / Q000166:cytology* / Q000648:ultrastructure; D005260:Female; D005775:Gastrula / Q000166:cytology; D008297:Male; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D009028:Morula / Q000166:cytology; D009865:Oocytes / Q000166:cytology*; D038081:Organogenesis; D015053:Zygote / Q000166:cytology
keywords: Embryo; Fish; Histology; Structure; Ultrastructure