Héctor M. Esparza-Leal

Detection of white spot syndrome virus in filtered shrimp-farm water fractions and experimental evaluation of its infectivity in Penaeus (Litopenaeus) vannamei.

Detection of white spot syndrome virus in filtered shrimp-farm water fractions and experimental evaluation of its infectivity in Penaeus (Litopenaeus) vannamei Héctor M. Esparza-Leal , César M. Escobedo-Bonilla , Ramón Casillas-Hernández , Píndaro Álvarez-Ruíz , Guillermo Portillo-Clark , Roberto C. Valerio-García , Jorge Hernández-López , Jesús Méndez-Lozano , Norberto Vibanco-Pérez , Francisco J. Magallón-Barajas d,⁎

Artisanal fisheries in the conservation zones of the Upper Gulf of California

Marine protected areas (MPAs) are increasingly being used as management tools to protect ecosystems around the world, but there is some debate as to whether ...

The Effect of Low Salinity Water with Different Ionic Composition on the Growth and Survival of Litopenaeus vannamei (Boone, 1931) in Intensive Culture

The effects of four different ionic composition low salinity water (T1, T2, T3, and T4), on growth and survival of Litopenaeus vannamei marine shrimp juveniles were investigated. Shrimp culture in seawater (Tm) was used as control treatment. The results indicated that there were no significant difference (P < 0.05) in growth, survival, production, and feed conversion ratio (FCR) of L. vannamei juveniles reared in the different treatments, but significant differences (P < 0.05) were observed between each of them when compared with seawater (Tm). After 84 days, culture shrimp grew from 0.02 to 7.58 g in T1. The lowest growth rate was attained in T3 (0.57 g/week), in which potassium and calcium ions concentrations were the lowest (0.58 and 28.00 mg/L, respectively). The recorded survival rate (76.35% to 79.55%) is considered well for the 84 days growout period, although it was 7.6% lower than that recorded in the control treatment. Although there were no significant differences (P < 0.05) in growth with respect to the ionic composition of the four treatments, there was a trend of increasing growth in relation with the ionic ratio found in the seawater (Tm). This aspect should be evaluated more closely in future research.

Analysis of management options for artisanal fishing of the Bigeye Croaker Micropogonias megalops (Gilbert, 1890) in the Upper Gulf of California

Bigeye Croaker (Micropogonias megalops Gilbert 1890) is captured in the Upper Gulf of California (UGC) by local community fishers from San Felipe in Baja California, El Golfo de Santa Clara and Puerto Peñasco in Sonora. The calculated sustainable fishery index (SFI) identifies four production periods, one of low capture before 1999 (∼1451.49 t year−1); a second of fleet expansion (∼2408 t year−1); a third showing a production decline related to overfishing (> 923.85 t year−1); and a fourth of recovery, with standardization of production of about 1057 t year−1 (2004). A GIS survey indicated that almost 84% of the Bigeye Croaker fishery in the UGC occurs within two marine protected areas, of which almost 74% takes place inside the Biosphere Reserve of the UGC, and almost 79% in the Vaquita Refuge Area. Bigeye Croaker captured in the marine protected areas generates a gross profit of around US

A response-surface analysis of the relative importance of the temperature, salinity and body weight on the respiratory metabolism of the white shrimp Litopenaeus vannamei (Boone, 1931)

501,000 year−1, with a return rate close to 73%. Fishing effort in the marine protected areas needs to undergo an interdisciplinary and complex evaluation due to the presence of endangered species in the region. This requires adequate management practices to enhance marine conservation without compromising fishermens individual interests. Some approaches to manage this fishery within the protected marine areas are discussed.

Efecto de diferentes combinaciones de temperatura y salinidad sobre el consumo específico de oxígeno en el camarón blanco Litopenaeus vannamei

We used a response-surface analysis to determine the importance of different factors affecting the resting routine metabolic rate (QO2) of the white shrimp Litopenaeus vannamei. The oxygen consumption rates were estimated using a multi-factorial design with 28 combinations of different salinities (15, 20, 25, 30, 35, 40 and 45 psu) and temperature (20, 25, 30 and 35 °C) values. The response-surface analysis produced a quadratic function showing that temperature more profoundly affects the oxygen consumption rate. Response-surface curves were generated to predict the optimal conditions resulting in oxygen consumption to better understand the successful growth of this species.

Ecology, Fishery and Aquaculture in Gulf of California, Mexico: Pen Shell Atrina maura (Sowerby, 1835)

The combined effect of different temperatures (20, 25 and 30°C) and salinities (15, 25, 35 and 45 psu) on the specific oxygen consumption (CEO) in Litopenaeus vannamei was determined. For this, CEO of 248 organisms of different body sizes (0.31 to 15.85 g) was measured. The CEO decreased when shrimp weight increased in all treatments without presenting a definite pattern when the salinity increased; even though all the combinations of temperature and salinity did not statistically show slopes significantly different in the regression models for CEO and organism weight relationships. The slope values suggest that at 20°C there is high energy expenditure at 15 psu, and at 25°C the highest energy consumption occurs at 45 psu. Whereas at 30°C, the lowest energy consumption occurred combined with the lowest salinity (15 psu). This may indicate that the isosmotic condition (point of lowest energy expenditure) tends to change with temperature, which may imply that the shrimp can be cultivated at high temperature (30°C) and at low salinities (15 psu) without increasing energy expenditure.

The effect of protein and lipid level on the specific dynamic action and post-prandial nitrogen excretion in subadult of white shrimp Litopenaeus vannamei

The pen shell Atrina maura bears economic importance in northwest Mexico. This chapter considers a review on diverse ecology, fishery, and aquaculture topics of this species, carried out in northwest Mexico. In ecology, biology, abundance, spatial prospecting, sex ratio, size structure, reproductive cycle, first maturity sizes, variation of gonadosomatic indexes and growth are discussed. In fishery, the information analysed corresponds to the structure of the organisms in the banks susceptible to capture, institutional and ecological interaction for fishing regulation, evaluation of fishing effort, improvement in fishing performance using the knowledge and attitudes of the fishermen on fisheries policies in the Gulf of California, resilience and collapse of artisanal fisheries and public politics. In aquaculture, they are long-line culture, bottom culture, reproductive cycle, growth, production of larvae and seeds, biochemistry of oocytes, nutritional quality of the muscle, evaluation of diets based on microalgae, immunology in larval and juvenile and probiotic use. The present work shows a status based on information published in theses and articles indexed 15 years ago to the date on the ecology, fishery and aquaculture in the pen shell Atrina maura carried out in the lagoon systems of northwest Mexico.

Use of organic and inorganic fertilization in zero-discharge tanks and ponds and its effects on plankton and shrimp Litopenaeus vannamei performance

espanolEl objetivo del estudio fue evaluar el efecto de 4 niveles de proteina (20, 30, 40 y 50%) y lipidos (2, 4, 8 y 16%) sobre la magnitud y duracion de la accion dinamica especifica (ADE) y la excrecion nitrogenada en subadultos del camaron blanco Litopenaeus vannamei usando una camara metabolica controlada por computadora (respirometro de flujo continuo). Se determino la tasa de consumo de oxigeno a intervalos de 1 hora hasta que la tasa de consumo de oxigeno postprandial regreso al nivel de pre-alimentacion. Los camarones alimentados con todas las dietas tienen una tasa de respiracion significativamente alta despues de la alimentacion debida a la ADE. El consumo de oxigeno, el coeficiente de ADE y la magnitud de ADE aumento notablemente con el incremento del contenido de proteina en la dieta. Los camarones alimentados con el 20% de proteina en la dieta tuvieron el nivel mas bajo de respiracion de pre y post-alimentacion y la mas baja ADE. Un cambio significativo en el coeficiente de ADE relativo a la energia digestible no fue demostrado para cada uno de los niveles de lipidos. Adicionalmente, la excrecion nitrogenada aumento con el incremento del nivel de proteina en la dieta, pero no con el incremento del nivel de lipidos. Al estimar la ADE de subadultos se encontro que la tasa metabolica estandar (SMR) fue menor que la reportada para juveniles y postlarvas de L. vannamei. EnglishThe study aimed to evaluate the effect of 4 levels of dietary protein (20, 30, 40 and 50%) and lipids (2, 4, 8 and 16%) on the magnitude and duration of specific dynamic action (SDA) and postprandial nitrogen excretion in the subadult white shrimp Litopenaeus vannamei using computer-controlled metabolic chambers (continuous-flow respirometer). We determined the oxygen consumption rate at 1 h intervals until the postprandial oxygen consumption rate returned to the pre-feeding level. Shrimp fed all the diets had significantly higher respiration rates after feeding due to the SDA. Oxygen consumption, the SDA coefficient and the SDA magnitude increased notably with increasing dietary protein content. Shrimp fed the 20% protein diet had the lowest levels of pre- and post-feeding respiration and the smallest SDA. A significant change in the SDA coefficient relative to each lipid level was not demonstrable. Additionally, nitrogenous excretion increased with an increase of dietary protein but not with an increase of lipid level. By estimating the SDA of subadults, the response to standard metabolic rate (SMR) was lower than that reported for juveniles and postlarva white shrimp.

Infection of WSSV-negative Shrimp, Litopenaeus vannamei, Cultivated under Fluctuating Temperature Conditions

The aim of this study was to investigate the effects of organic (molasses) and inorganic (Nutrilake®) fertilization on plankton, water quality, and shrimp Litopenaeus vannamei performance reared in zero-discharge tanks and ponds. The findings showed that in tanks, the organic fertilization induced highest survival and production, and low total ammonia-N concentration; however, this effect was not observed in the ponds. In both tanks and ponds, the inorganic fertilization increased nitrogen levels. The phytoplankton abundance increased in both tanks/ponds with the fertilization treatments. Shrimp production in the tanks and ponds fertilized almost doubled compared with unfertilized treatments.