958 resultados para Shrimp, Crustacean


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Máster Universitario International en Acuicultura. Trabajo presentado como requisito parcial para la obtención del Tí­tulo de Máster Universitario Internacional en Acuicultura, otorgado por la Universidad de Las Palmas de Gran Canaria (ULPGC), el Instituto Canario de Ciencias Marinas (ICCM), y el Centro Internacional de Altos Estudios Agronómicos Mediterráneos de Zaragoza (CIHEAM)

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Tolerance to low temperature and high pressure may allow shallow-water species to extend bathymetric range in response to changing climate, but adaptation to contrasting shallow-water environments may affect tolerance to these factors. The brackish shallow-water shrimp Palaemon varians demonstrates remarkable tolerance to elevated hydrostatic pressure and low temperature, but inhabits a highly variable environment: environmental adaptation may therefore make P. varians tolerances unrepresentative of other shallow-water species. Critical thermal maximum (CTmax), critical hydrostatic pressure maximum (CPmax), and acute respiratory response to hydrostatic pressure were assessed in the shallow-water shrimp Palaemon serratus, which inhabits a more stable intertidal habitat. P. serratus’ CTmax was 22.3°C when acclimated at 10°C, and CPmax was 5.9, 10.1, and 14.1 MPa when acclimated at 5, 10, and 15°C respectively: these critical tolerances were consistently lower than P. varians. Respiratory responses to acute hyperbaric exposures similarly indicated lower tolerance to hydrostatic pressure in P. serratus than in P. varians. Contrasting tolerances likely reflect physiological adaptation to differing environments and reveal that the capacity for depth-range extension may vary among species from different habitats.

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The spatio-temporal distribution of megistobenthic crustacean assemblages from the Antalya Gulf, located in the Levantine Sea is described. In order to provide a comprehensive overview of the spatio-temporal patterns of the crustacean community, 3 transect including depth of 10, 25, 75, 125 and 200 m, were studied between 2014 and 2015 to investigate their association with a set of environmental parameters in representative months of each season (spring, summer, autumn and winter). For its economic importance in Levantine waters, a focus analysis of deep-water rose shrimp Parapenaeus longirostris (Lucas, 1846) was done, to investigate the length frequency composition of the population of the Antalya Gulf. A total of 58 crustacean species were encountered in the study area, of these species identified, 18 species were recognized as alien species in the Mediterranean Sea. Throughout the year the most frequent species of the study were the hermit crab Pagurus prideaux (Leach, 1815) and Parapenaeus longirostris (Lucas, 1846) followed by the Indo-Pacific swimming crab Charybdis longicollis (Leene, 1938) and by the invasive shrimp Marsupenaeus japonicus (Spence Bate, 1888). Few species contributing to a high amount to the total biomass were found throughout the year. These species were Charybdis longicollis and Parapenaeus longirostris. Stations of the study area showed similar values of diversity indices of benthic crustacean community among the three transect. The highest values of faunistic indices were detected in autumn and winter (October and February), and also varied along the depth gradient, with the highest values found between 25 and 75 meters. The multivariate analyses conducted on the abundance data point out major differences between depths and between seasons. Therefore, according to cluster analysis and ordination over abundance and biomass, three main crustacean assemblages were detected: the first corresponding to shallow bottoms (10, 25 meters), the second corresponding to intermediate waters (75 meters) and the last to deeper waters (125, 200 meters). Depth was the main factor governing the distribution of megistobenthic crustacean in the area. Besides the depth, the structure of the sediment is the most important factor in determining the crustacean assemblage. Therefore, all factors governing the crustacean distribution were found to be related to the bottom depth. The population of Parapenaeus longirostris in the Antalya Gulf showed significant differences in depth. It was found that females dominated the population of the study area (65.11%), and were significantly larger than males for each cohort identified. The size-weight relationships revealed a slight negative allometry in growth, a bit more pronounced in females than in males.

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Background: The shrimp Nematocarcinus lanceopes Bate, 1888 is found in the deep sea around Antarctica and sub-Antarctic islands. Previous studies on mitochondrial data and species distribution models provided evidence for a homogenous circum-Antarctic population of N. lanceopes. However, to analyze the fine-scale population genetic structure and to examine influences of abiotic environmental conditions on population composition and genetic diversity, a set of fast evolving nuclear microsatellite markers is required. Findings: We report the isolation and characterization of nine polymorphic microsatellite markers from the Antarctic deep-sea shrimp species Nematocarcinus lanceopes (Crustacea: Decapoda: Caridea). Microsatellite markers were screened in 55 individuals from different locations around the Antarctic continent. All markers were polymorphic with 9 to 25 alleles per locus. The observed heterozygosity ranged from 0.545 to 0.927 and the expected heterozygosity from 0.549 to 0.934. Conclusions: The reported markers provide a novel tool to study genetic structure and diversity in Nematocarcinus lanceopes populations in the Southern Ocean and monitor effects of ongoing climate change in the region on the populations inhabiting these.

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The combined effects of salinity, temperature and cadmium stress on survival and adaptation through cadmium-binding protein (CdBP) accumulation were studied in the grass shrimp, Palaemonetes pugio. In 96-hour bioassays, shrimp were exposed to zero or one of three levels of cadmium, under one of six different salinity (15, 25, or 35$\perthous$) and temperature (20 or 30$\sp\circ$C) regimes. CdBP concentrations were quantified in survivors from the 24 exposure groups. Salinity and temperature did not affect survivorship unless the shrimp were also exposed to cadmium. Grass shrimp were most sensitive to cadmium at low salinity-high temperature, and least sensitive at high salinity-low temperature. The incidence of cadmium-associated black lesions in gill tissue was influenced by salinity and temperature stress. P. pugio produced a 10,000 dalton metallothionein-like CdBP when exposed to at least 0.1 mg Cd$\sp{2+}$/L for 96 hours. Accumulation of CdBP was increased with increases in the exposure cadmium level, increases in temperature and decreases in salinity, independently and in conjunction with one another. Maximum CdBP concentrations occurred in grass shrimp that survived the salinity-temperature-cadmium conditions creating maximum stress as measured by highest mortality, not necessarily in shrimp exposed to the highest cadmium levels. The potential utility of this method as a monitor of physiological stress in estuarine biota inhabiting metal-polluted environments is discussed. ^