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| Brito,P; Salles,FF; Dolder,H. |
| This study describes morphological changes in the male reproductive system of Miroculis amazonicus (Savage & Peters) from mature nymphs to subimago stages. The sperm ultrastructure of Massartela brieni (Lestage), Farrodes carioca (Domínguez et al) and Miroculis mourei (Savage & Peters), as well as aspects of cell fragments observed in these species' subimagos deferent ducts were described. Sperm from the three species studied are aflagellated and immotile, while those from F. carioca and Ma. brieni are approximately spherical with a homogenous nucleus and acrosome. Sperm of F. carioca present two or three mitochondria located between the nucleus and the acrosome. In Ma. brieni, only one lateral mitochondria was found. Sperm from Mi. mourei... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Morphology; Sperm; Aflagellate; Sexual maturation. |
| Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1519-566X2011000100015 |
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| Gagnaire, Beatrice; Soletchnik, Patrick; Madec, Patrick; Geairon, Philippe; Le Moine, Olivier; Renault, Tristan. |
| Summer mortality is an important economic concern for the Pacific oyster, Crassostrea gigas, industry all over the world and particularly in France. Outbreaks appear when oysters are in gonadal maturation. Bivalve defence mechanisms against pathogen invasion are assumed by circulating cells, the hemocytes. A field experiment was conducted in the Marennes-Oleron Basin (Charente-Maritime, France) in order to monitor hemocyte parameters, gametogenesis and mortality rates among C. gigas during 7 months from March to September 2002. Diploid (from natural bed and from hatchery) and triploid oysters were placed at 15 cm or 70 cm above sediment at Marennes-Oleron Basin. Triploid animals were included because they are considered as sterile animals. Mortality rates... |
| Tipo: Text |
Palavras-chave: Sexual maturation; Summer mortality; Triploids; Diploids; Flow cytometry; Hemocyte activities; Crassostrea gigas; Pacific oyster. |
| Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-2923.pdf |
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| Veras,Galileu Crovatto; Murgas,Luis David Solis; Rosa,Priscila Vieira; Zangeronimo,Márcio Gilberto; Ferreira,Matheus Soares da Silva; Leon,Jonathan Antonio Solis-De. |
| The objective of this study was to evaluate the effect of photoperiod on locomotor activity, growth and gonadal development in Nile tilapia (Oreochromis niloticus) fingerlings. A completely randomised design was used, with five treatments (0L:24D, 6L:18D, 12L:12D, 18L:6D and 24L:0D) and four replicates, with the aquarium as the experimental unit. One hundred and sixty fingerlings of tilapia weighing 3.21±0.05 g and measuring 4.35±0.07 cm each were distributed among 20 aquaria of 20 L in a recirculation system with the temperature controlled to 27 °C, with eight fish per aquarium. Feeding was carried out twice daily for 75 days, with extruded feed containing 40% crude protein. The fingerlings subjected to a photoperiod of 12L:12D as well as those under... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Feed intake; Fish; Locomotor rhythm; Oreochromis niloticus; Performance; Sexual maturation. |
| Ano: 2013 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982013001200002 |
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| Brunel, Thomas; Ernande, Bruno; Mollet, Fabian M.; Rijnsdorp, Adriaan D.. |
| A new method is presented to estimate individuals’ (1) age at maturation, (2) energy acquisition rate, (3) energy expenditure for body maintenance, and (4) reproductive investment, and the multivariate distribution of these traits in a population. The method relies on adjusting a conceptual energy allocation model to individual growth curves using nonlinear mixed-effects modelling. The method’s performance was tested using simulated growth curves for a range of life-history types. Individual age at maturation, energy acquisition rate and the sum of maintenance and reproductive investment rates, and their multivariate distribution, were accurately estimated. For the estimation of maintenance and reproductive investment rates separately, biases were observed... |
| Tipo: Text |
Palavras-chave: Bioenergetics growth model; Individual growth trajectory; Life-history trade-offs; Energy acquisition; Maintenance; Reproductive investment; Sexual maturation. |
| Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00124/23537/21378.pdf |
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| Lemos,Valéria M.; Varela Junior,Antônio S.; Velasco,Gonzalo; Vieira,João P.. |
| The Plata pompano, Trachinotus marginatus (Cuvier, 1832), is an endemic carangid of the Southwestern Atlantic Ocean, occurring from Rio de Janeiro to Uruguay. This study describes the reproductive period, spawning type, the size at first gonadal maturation and the length-weight relationship of individuals sampled from landings of the artisanal and commercial fishing fleets in Rio Grande that operate along the coast of Rio Grande do Sul state, southern Brazil (~ 32ºS) to the Uruguayan border (~ 34ºS). Monthly collections from September 2008 through January 2010 yielded 274 individuals ranging from 142 to 444 mm in total length (TL). The gonadal development stages were defined according to the histological examination of the ovaries and the testes. The... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Reproductive period; Sexual maturation; Spawning; Weight-length relationship. |
| Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1984-46702011000500008 |
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