Effect of darkness on the early postlarval development of Haliotis corrugata abalone fed different diatom densities

Four-day-old postlarvae of the abalone Haliotis corrugata were exposed to different diatom densities (Navicula incerta, 0 to 8000 cells mm-2) under two illumination conditions: constant light (19-21 ¿mol quanta m-2 s-1) and darkness. The effect of these two factors on postlarval grazing rate, surviv...

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Detalles Bibliográficos
Autores: E Gorrostieta-Hurtado, R Searcy-Bernal, C Anguiano-Beltrán, Z García-Esquivel, E Valenzuela-Espinoza
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2009
País:México
Institución:Universidad Autónoma de Baja California
Repositorio:Redalyc-UABC
OAI Identifier:oai:redalyc.org:48013192009
Acceso en línea:https://www.redalyc.org/articulo.oa?id=48013192009
Access Level:acceso abierto
Palabra clave:Ciencias de la Tierra
growth
Abalone
darkness
postlarvae
Haliotis corrugata
Descripción
Sumario:Four-day-old postlarvae of the abalone Haliotis corrugata were exposed to different diatom densities (Navicula incerta, 0 to 8000 cells mm-2) under two illumination conditions: constant light (19-21 ¿mol quanta m-2 s-1) and darkness. The effect of these two factors on postlarval grazing rate, survival, and growth was evaluated. The experiment was conducted for 14 days in 10-mL sterile wells following a split-plot experimental design with three replicates per treatment. The highest grazing rate was observed in the 2000 cells mm-2 density treatment and it was higher in darkness (196 ± 67 cells pl-1 h-1) than in constant light (139 ± 36 cells pl-1 h-1). Mean survival was also higher in darkness (59%) than under constant light (44%), as was mean growth rate (20 and 14 ¿m d-1, respectively). Growth rate at the end of the experimental period tended to decrease with the increase in diatom density. Higher grazing and growth rates in darkness reinforce the hypothesis that the nocturnal habits of abalone develop soon after metamorphosis and not at juvenile stages as usually considered.