Data/hora: 01/06/2024 09:01:23

Provedor de dados: 	52	
País: 	Brazil	
Título: 	Oocyte surface in four teleost fish species postspawning and fertilization	
Autores: 	Rizzo,Elizete; Moura,Thais F.C.; Sato,Yoshimi; Bazzoli,Nilo.	
Data: 	1998-06-01	
Ano: 	1998	
Palavras-chave: 	Zona pellucida; Oocyte surface; Mucous coat; Teleost; Micropyle.	
Resumo: 	Cytological and cytochemical studies were carried out to investigate the surface characteristics of oocytes of four teleost species from the São Francisco river. The fishes were submitted to hypophysation at the Três Marias Hybrobiology and Fishculture Station, Minas Gerais, Brazil, in January 1996. Postspawning, oocytes of the curimatãs Prochilodus affinis, Prochilodus marggravii and dourado Salminus brasiliensis were surrounded by a thick, three-layered zona pellucida with radial striae. The surface of spawned oocytes of the surubim, Pseudoplatystoma coruscans, was comprised of mucous coat located externally to a thin, two-layered and striated zona pellucida. Oocyte activation during fertilization, lead to cortical reaction, formation of a perivitelline space, reduction of the thickness of the zona pellucida and increase in the oocyte diameter in the four species. Following fertilization, many spermatozoa were embedded in the mucous coat of the surubim oocytes. During embryogenesis, this later coating became thicker, diffuse and less viscous while the zona pellucida (chorion) was thinner in all studied species. Cytochemical analyses indicated species-specific differences in the oocyte surface after spawning. It was suggested that the mucous coat of surubim oocytes play a functional role during fertilization. The knowledge of the morphology of the oocyte surface of teleost is important for our understanding of the interactions between their eggs and surrounding environment and may also contribute significantly to phylogenetic studies.	
Tipo: 	Info:eu-repo/semantics/article	
Idioma: 	Inglês	
Identificador: 	http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89131998000100005	
Editor: 	Instituto de Tecnologia do Paraná - Tecpar	
Relação: 	10.1590/S1516-89131998000100005	
Formato: 	text/html	
Fonte: 	Brazilian Archives of Biology and Technology  v.41 n.1 1998	
Fonte: 	info:eu-repo/semantics/openAccess