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Tese
Avaliação da atividade gonadal de machos e fêmeas de pescada branca, Plagioscion squamosissimus (Heckel, 1840), (Pisces, Teleostei, Sciaenidae) no rio Pará (PA)
Male and female adults of P. squamosissimus (Pisces, Teleostei, Sciaenidae) were collected monthly in the Para River that surrounds Capim insland, state of Para (S 010 34. 971` ; W 0480 52.932`), during the month of february 2004 to february 2005, having 234 specimes. The gonads were collected, mo...
Autor principal: | NEGRÃO, José Nazareno Cunha |
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Grau: | Tese |
Idioma: | por |
Publicado em: |
Universidade Federal do Pará
2013
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Assuntos: | |
Acesso em linha: |
http://repositorio.ufpa.br/jspui/handle/2011/4449 |
Resumo: |
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Male and female adults of P. squamosissimus (Pisces, Teleostei, Sciaenidae) were collected monthly in the Para River that surrounds Capim insland, state of
Para (S 010 34. 971` ; W 0480 52.932`), during the month of february 2004
to february 2005, having 234 specimes. The gonads were collected, mounted
and processed in accordance with the standard methods of paraffin and
analysis using a light microscope. The species under analysis is one of the
principal sources of animal protein for the local population, fishing being
uninterrupted and intensive throughout the year based on information given by
local fisherman, the collection process appears to be determined by an
apparent qualiquantitative reduction in local stock. The species represents
spawn divisions, the gonad development was characterized in state of repose,
maturation, mature and empty or half-empty. Mature gonads were found on the
months of december, january and july. Correlation analysis between the
maturing state of gonads, seasonal variations in relation to gonadosomatic
indexes (GSI) and also the occurrence of spawn in the respective months.
Nevertheless, the information obtained in correlation to GSI and mature oocyte
mediums and between spermatozoa percentages by seminiferous tubule,
respectively, also indicate spawning in the respective months, and apparently
that the species represents a more intensive spawning period or a primary
spawning period between the months of december and january, and a second
or less intensive spawning period in the months of july. Based on the tubular
morphology method, eight of the seminiferous epithelium cycle stages (SEC)
were determined, stage 1 being seminiferous tubule that are comprised of
primary spermatogonia and cysts of the secondary spermatogonia; stage 2 is
comprised of primary and seconday spermatogonia and spermatocytes cysts;
stage 3 is characterized by primary and secondary spermatogonias,
spermatocyte cysts and young spermatids; stage 4 with seminiferous tubule
characterized by presence of spermatogonias primary and secondary,
spermatocyte and by presence of young and later spermatids cysts; stage 5
represents all of the previously mentioned cells and is highlighted by presence
of spermatozoa in the tubule lumen; stage 6 is characterized by reduction of
cysts of germinative cells and a considerable increase in number of
spermatozoa in the tubular lumen; stage 7 is characterized by seminiferous
tubule that contain few cysts of germinative cells and is marked by the begining
of a mass emptying of spermatozoa of the tubule lume; stage 8 is the last of the
SEC and is characterized by the apparent disorganization of the remaining
germinative cellular cysts in the seminiferous tubule. |