| Summary: | 碩士 === 國立臺灣海洋大學 === 水產養殖學系 === 105 === The purpose of this study was to investigate the optimal conditions in larvae culture of Amano shrimp (Caridina multidentata) in order to apply the knowledge background to the commercial production of the ornamental shrimp industry.The major factors were salinity, microalgalspecies, algalfeeding density, shrimp larvae culture density.There were five treatments (3 replicates), 15‰, 20‰, 25‰, 30‰ and 34‰ for the salinity experiment. The four microalgalspecies, Thalassiosira weissflogii; Tetraselmis Chui; Isochrysis galbana; Chaetoceros gracilis, were compared at the same density of 2 x105cells/ml (three replicates) to feed the shrimp larvae. Of the algaldensity feeding experiment, Tetraselmis Chui and Thalassiosira weissflogii were chosen and fed to shrimp larvae at three densities (3 replicates): (2 x 105 cells/ml), (4 x 105 cells/ml) and (6 x 105cells/ml). Larval stocking densities were set at 30，60，90 individuals/L (3 replicates). All the above experiments were carried out between 26-28℃ with 100L-container except those of salinity experiments using 2L-beaker.
Of the survival rate of the successfully metamorphosed larvae, the two highest treatments at salinities of 20‰ (61.1%) and 15‰ (51.1%) were significantly higher than those at salinities of 30‰ (32.2%), 25‰ (27.7%) and 34‰ (25.5%).It was found that the metamorphosed larval survivals (%) and the averaged juvenile required metamorphosed duration (days) upon the feeding pre-tests of four algalspecies at the same density level of 2 x 105 cells/ml revealed that those values for Thalassiosira weissflogii (40.8%, 15 days) and Tetraselmi Chui (35.2%, 15 days) were significantly higher than those of Isochrysis galbana (13.2%, 25 days) and Chaetoceros gracilis (9.4%, 25 days). Of algaldensity feeding experiment, Tetraselmis Chui at density level of 2 x 105 cells/ml (36.1%, 15 days) were the highest, followed by those at 4x105 cells/ml (26%, 21days), and those at 6x105 cells/ml (18.2%, 25days) the worst. As for Thalassiosira weissflogii, the values of survivals and metamorphosed duration at density level of 2x105cells/ml (41.8%, 15days) were significantly higher than those at 4x105cells/ml (22.5%, 19days), while those at 6x105 cells/ml perished completely on day 11. The values of survivals (%) and juvenile metamorphosed duration (days) of shrimp larval groups reared at the density of 30 individuals/L (36.8%, 15days) and at 60 individuals /L (33.4%, 17 days) were significantly higher than those at 90 individuals /L (20%, 19days). It was concluded that Tetraselmis Chui be used as the main food in Caridina multidentata larvae culture at density level of 2 x105 cells/ml with larvae stocking density levels between 30-60 individuals/L and salinity at 20‰.
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