Consulta: subjectFacets:"Atresia"
Registros recuperados: 4
Data/hora: 11/06/2024 10:09:36

Ciclo gametogênico e comportamento reprodutivo de Iphigenia brasiliana (Mollusca, Bivalvia, Donacidae) no estuário do rio Subaé, Baía de Todos os Santos, Bahia, Brasil
Provedor de dados: 76
Autores: Silva,Patrícia P.; Peso-Aguiar,Marlene C.; Ribeiro,Gabriel.
Este estudo teve como objetivos descrever o ciclo gametogênico e o comportamento reprodutivo da população de Iphigenia brasiliana (Lamarck,1818) no estuário do rio Subaé, Baía de Todos os Santos, Bahia. Os bivalves foram coletados de novembro de 2001 a novembro de 2002. Um total de 244 espécimes foi medido (eixo anteroposterior), eviscerado, fixado, desidratado e incluído em parafina. O estudo histológico das gônadas foi realizado através de cortes seriados do tecido gonadal, de 5 mm de espessura, e corados pela HE. O tamanho médio mínimo da primeira maturação sexual (Lpm) foi estimado a partir da distribuição das frequências relativas de jovens e adultos, por classe de comprimento dos indivíduos. As frequências relativas dos sexos em cada estádio de...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Desenvolvimento gonadal; Proporção sexual; Primeira maturação; Atresia; Hermafroditismo.
Ano: 2012
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0073-47212012000400001

Long-term food-exposure of zebrafish to PCB mixtures mimicking some environmental situations induces ovary pathology and impairs reproduction ability
Provedor de dados: 5
Autores: Daouk, Tarek; Larcher, Thibaut; Roupsard, Francois; Lyphout, Laura; Rigaud, Cyril; Ledevin, Mireille; Loizeau, Veronique; Cousin, Xavier.
Although the use of polychlorinated biphenyls (PCBs) has been banned for several decades, they are still present in the environment and are occasionally mechanically released from sediment or transferred through the trophic chain. Field analyses have established correlations between exposure to PCBs and alterations in fish physiology including reproductive function. Experimental exposures have been mainly performed using dioxin-like PCBs or other congeners at very high concentrations. However, these studies are often difficult to relate to real-life conditions. In the present study, we performed a life-cycle exposure using zebrafish model and mixtures representative of some environmental situations in terms of doses, composition and containing mainly non...
Tipo: Text
Palavras-chave: Zebrafish; PCBs; Chronic exposure; Physiology; Reproduction; Atresia.
Ano: 2011
URL: http://archimer.ifremer.fr/doc/00059/17038/14608.pdf

Temperature and seston quantity and quality effects on field reproduction of farmed oysters, Crassostrea gigas, in Bourgneuf Bay, France
Provedor de dados: 5
Autores: Dutertre, Mickael; Beninger, Peter G.; Barille, Laurent; Papin, Mathias; Rosa, Philippe; Barille, Anne-laure; Haure, Joel.
The proliferation of the voluntarily-introduced cupped oyster, Crassostrea gigas, has attained the proportions of species invasion in many intertidal habitats in Europe, presumably resulting from successful reproduction of farmed individuals. It is thus imperative to better understand the reproductive characteristics of farmed oysters, since they are directly under human control. We quantified the dry tissue mass (DTM), gametosomatic index (GSI), and reproductive cycle of farmed oysters at two sites in Bourgneuf Bay, France, in relation to environmental parameters using continuously-recording probes in 2005 and 2006. The GSI was developed for this study, based on the actual area occupied by gametes, rather than the area of the gonad previously used for...
Tipo: Text
Palavras-chave: Atlantic Ocean; Crassostrea gigas; Oyster farming; Bivalve; Gametosomatic index; Biological invasion; Atresia; Oocytes; Turbidity; Temperature; Reproduction.
Ano: 2009
URL: http://archimer.ifremer.fr/doc/2009/publication-6871.pdf

Growth hormone on ovarian morphology of lambaris (Astyanax bimaculatus) after induced spawning
Provedor de dados: 65
Autores: Marcon,Lucas; Freitas,Vivian Rocha; Bazzoli,Nilo; Rizzo,Elizete; Benjamin,Laércio dos Anjos.
ABSTRACT:  Lambari, Astyanax bimaculatus, is an oviparous, multiple-spawning fish that is reproductively active throughout the year, which makes it promising for cultivation and research. This research histologically evaluates the ovaries of lambari that have undergone artificial spawning induced with pituitary extract (control group), and the effect of growth hormone at a dose of 2 mg/g body weight (treatment group) on the subsequent process of ovarian recovery. Ovaries of fish in both the control and treatments groups were collected at 120 hours after spawning and analyzed using optical microscopy to characterize the average quantities of: follicles in different stages of development, post-ovulatory follicles, follicular atresia and granulocytes....
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Atresia; Granulocytes; Post-ovulatory follicles; Freshwater fishes.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782019000800651