The scallop Nodipecten subnodosus is the largest pectinid species targeted in Mexico for hatchery seed production. Thus, effects of larval density (LD = 5, 10 and 15 ml−1) and food concentration ...(FC = 15,000; 30,000; 45,000 and 60 cells ml−1) were assessed on survival (S) and growth. Clearance (CR) and ingestion rates (IR) were also studied. Lowest S was observed at 15,000 cells ml−1 (19%–22%), while S > 50% prevailed at ≥30,000 cells ml−1. Both LD and FC significantly affected gross growth rate (GGR), with maximal values (7.3 µm d−1) observed at 5 larvae ml−1. Mean GGR of 6.1 to 6.9 µm d−1 was recorded at 10–15 larvae ml−1 and 45,000 to 60,000 cells ml−1. Maximal CR (13.8–23 ml larva−1 h−1) was recorded at 15 cells ml−1. Ingestion rates increased as FC increased, reaching asymptotic values (9.7–11.5 cells larva−1 min−1) at 45,000 and 60,000 cells ml−1. Allometric IR—Shell height exponents increased (b = 1.1 to 1.9) as FC increased. The combined results suggest that N. subnodosus larvae may be reared at stocking densities from 5 to 15 larva ml−1 and reach maximal GGR if fed 45,000 to 60,000 cells ml−1.
The reproductive strategy of lion’s paw scallop Nodipecten subnodosus was evaluated in a culturing system in Bahía Tortugas, Baja California Sur, Mexico during an annual cycle, comparing its response ...with data previously reported at other localities. High frequencies of ripe gonads throughout the year indicate that reproduction was continuous, with two main ripening/spawning events: July-September and December-March. A continuous breeding is also reported for the species in Bahía Magdalena, Bahía Juncalito, and Bahía de Los Angeles. These eutrophic areas are Biological Active Centers where gametogenesis appears to be regulated by the energy taken from recently ingested food following an opportunistic strategy. However, the digestive gland index decreased and the muscle indices increased during one of the breeding peaks, suggesting that some stored reserves are also used to sustain gametogenesis (conservative strategy) partially. High incidences of atretic oocytes are likely associated with atypical daily variations in water temperature from May through September (12 to 33°C), or with stressful conditions in the culturing system in summer. Despite this, the culturing system set in Bahía Tortugas appears beneficial for a continuous reproduction of N. subnodosus.
The reproductive strategy of lion's paw scallop Nodipecten subnodosus was evaluated in a culturing system in Bahia Tortugas, Baja California Sur, Mexico during an annual cycle, comparing its response ...with data previously reported at other localities. High frequencies of ripe gonads throughout the year indicate that reproduction was continuous, with two main ripening/spawning events: July-September and DecemberMarch. A continuous breeding is also reported for the species in Bahia Magdalena, Bahia Juncalito, and Bahia de Los Angeles. These eutrophic areas are Biological Active Centers where gametogenesis appears to be regulated by the energy taken from recently ingested food following an opportunistic strategy. However, the digestive gland index decreased and the muscle indices increased during one of the breeding peaks, suggesting that some stored reserves are also used to sustain gametogenesis (conservative strategy) partially. High incidences of atretic oocytes are likely associated with atypical daily variations in water temperature from May through September (12 to 33°C), or with stressful conditions in the culturing system in summer. Despite this, the culturing system set in Bahia Tortugas appears beneficial for a continuous reproduction of N. subnodosus. Keywords: culturing system, gametogenesis, lion's paw scallop, lipid index, morpho-physiological indices, reproductive strategy. La estrategia reproductiva de la almeja mano de leon Nodipecten subnodosus se estudio en un sistema de cultivo en Bahia Tortugas, Baja California Sur, Mexico durante un ciclo anual, comparando su respuesta con datos previamente reportados para otras localidades. La alta frecuencia de gonadas maduras durante todo el ano indica que la reproduccion es continua, con dos eventos principales de madurez/desove: julio-septiembre y diciembre-marzo. Una gametogenesis continua tambien se reporta para esta especie en Bahia Magdalena, Bahia Juncalito y Bahia de Los Angeles. Estas areas eutroficas son Centros de Actividad Biologica, donde la gametogenesis estaria regulada por la energia del alimento recientemente ingerido siguiendo una estrategia oportunista. Sin embargo, el indice de la glandula digestiva disminuyo y el indice del musculo aumento durante uno de los maximos de madurez, indicando un uso parcial de reservas energeticas para sustentar la gametogenesis (estrategia conservadora). La alta incidencia de ovocitos atresicos se atribuye a variaciones diarias atipicas en la temperatura de mayo a septiembre (12 a 38°C) o a condiciones estresantes en el sistema de cultivo en verano. Sin embargo, Bahia Tortugas parece beneficiar una reproduccion continua de N. subnodosus. Palabras clave: sistema de cultivo, gametogenesis, almeja mano de leon, indice lipidico, indices morfofisiologicos, estrategia reproductiva.
The reproductive strategy of lion's paw scallop Nodipecten subnodosus was evaluated in a culturing system in Bahia Tortugas, Baja California Sur, Mexico during an annual cycle, comparing its response ...with data previously reported at other localities. High frequencies of ripe gonads throughout the year indicate that reproduction was continuous, with two main ripening/spawning events: July-September and DecemberMarch. A continuous breeding is also reported for the species in Bahia Magdalena, Bahia Juncalito, and Bahia de Los Angeles. These eutrophic areas are Biological Active Centers where gametogenesis appears to be regulated by the energy taken from recently ingested food following an opportunistic strategy. However, the digestive gland index decreased and the muscle indices increased during one of the breeding peaks, suggesting that some stored reserves are also used to sustain gametogenesis (conservative strategy) partially. High incidences of atretic oocytes are likely associated with atypical daily variations in water temperature from May through September (12 to 33°C), or with stressful conditions in the culturing system in summer. Despite this, the culturing system set in Bahia Tortugas appears beneficial for a continuous reproduction of N. subnodosus.
The reproductive strategy of lion's paw scallop Nodipecten subnodosus was evaluated in a culturing system in Bahía Tortugas, Baja California Sur, Mexico during an annual cycle, comparing its response ...with data previously reported at other localities. High frequencies of ripe gonads throughout the year indicate that reproduction was continuous, with two main ripening/spawning events: July-September and December-March. A continuous breeding is also reported for the species in Bahía Magdalena, Bahía Juncalito, and Bahía de Los Angeles. These eutrophic areas are Biological Active Centers where gametogenesis appears to be regulated by the energy taken from recently ingested food following an opportunistic strategy. However, the digestive gland index decreased and the muscle indices increased during one of the breeding peaks, suggesting that some stored reserves are also used to sustain gametogenesis (conservative strategy) partially. High incidences of atretic oocytes are likely associated with atypical daily variations in water temperature from May through September (12 to 33°C), or with stressful conditions in the culturing system in summer. Despite this, the culturing system set in Bahía Tortugas appears beneficial for a continuous reproduction of N. subnodosus.
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