Structural analysis of fertilization in the fish Brycon orbignyanus


Autoria(s): Ganeco, Luciana Nakaghi; Franceschini-Vicentini, Irene Bastos; Okada Nakaghi, Laura Satiko
Contribuinte(s)

Universidade Estadual Paulista (UNESP)

Data(s)

20/05/2014

20/05/2014

01/05/2009

Resumo

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

In the present work, we analyzed the structure of oocytes and fertilized eggs of the piracanjuba fish (Brycon orbignyanus) under light and scanning electron microscopy. After inducing spawning, samples were collected at the moment of oocyte extrusion, when oocytes and semen were mixed (time 0), as well as at 10, 20 and 30s after mixing, every minute up to 10 min, and then at 15 and 20 min. The oocytes are spherical, translucent and greenish with a mean diameter of 1.3 +/- 0.11 mm. During the extrusion, cytoplasmic movement was observed in eggs towards the micropyle, characterizing the animal pole. At the moment of fertilization, the cortical cytoplasm showed a higher concentration of cortical alveoli at the animal pole than at the vegetal pole. The cortical alveoli breakdown promoted the elevation of the chorion with a consequent increase in egg diameter (1.95 +/- 0.08mm). The penetration of the spermatozoon promotes the formation of a fertilization cone of spherical external structure, which obstructs the opening of the micropyle. This structure acts as a main mechanism to avoid polyspermy, intercepting the access of supernumerary spermatozoa. Such studies about the reproductive biology of fish are important to species survival and conservation programmes.

Formato

93-99

Identificador

http://dx.doi.org/10.1017/S0967199408005030

Zygote. New York: Cambridge Univ Press, v. 17, n. 2, p. 93-99, 2009.

0967-1994

http://hdl.handle.net/11449/8260

10.1017/S0967199408005030

WOS:000265174700001

WOS000265174700001.pdf

Idioma(s)

eng

Publicador

Cambridge University Press

Relação

Zygote

Direitos

closedAccess

Palavras-Chave #Egg #Fertilization #Fish #Micropyle #Microscopy
Tipo

info:eu-repo/semantics/article