Consulta: creatorFacets:"Chavez-villalba, Jorge"
Registros recuperados: 2
Data/hora: 09/06/2024 06:41:33

Determination of gender in the pearl oyster pinctada margaritifera
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Chavez-villalba, Jorge; Soyez, Claude; Huvet, Arnaud; Gueguen, Yannick; Lo, Cedrik; Le Moullac, Gilles.
The pearl industry in French Polynesia is based on exploitation of natural stocks of the black-lip pearl oyster (Pinctada margaritifera); it generates an annual turnover of 90 million euros. Improvements in pearl quality need genetic studies to improve the populations. This pearl oyster is a protandric species, where the sex-ratio normally is biased towards males. There is an increasing interest in gender control to find the mechanisms to augment female proportions for management purposes. This review summarizes information on exogenous and endogenous factors regulating gender in this and other bivalves and concludes that P. margaritifera is a protandric hermaphrodite, developing as a male during the first two years and without evidence of an effect from...
Tipo: Text
Palavras-chave: Pearl oyster; Pinctada; Hermaphrodite; Temperature; Food; Stress; Sex genes; Sex steroids.
Ano: 2011
URL: http://archimer.ifremer.fr/doc/00040/15100/12543.pdf

Physiological responses of female and male black-lip pearl oysters (Pinctada margaritifera) to different temperatures and concentrations of food
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Chavez-villalba, Jorge; Soyez, Claude; Aurentz, Hermann; Le Moullac, Gilles.
This study was designed to measure responses of four-year-old black-lip pearl oysters (Pinctada margaritifera) to different temperatures and food concentrations and to identify the energy requirements of each sex. Oysters were fed a monospecific microalgal diet of Isochrysis affinis galbana (T-iso). Measurements of oxygen consumption and ingestion rates were carried out at 24 degrees C and 27 degrees C and at two algal (T-iso) concentrations: 5000 and 30 000 cell ml(-1). Glycogen content in adductor muscle, absorption efficiency and scope for growth were also estimated. Females and males responded differently to environmental factors, with food level being the most influential parameter. Oxygen consumption and absorption efficiency were significantly...
Tipo: Text
Palavras-chave: Food supply; Ingestion rate; Glycogen; Oxygen consumption; Scope for growth; Pearl oyster.
Ano: 2013
URL: http://archimer.ifremer.fr/doc/00157/26855/24980.pdf