Pilot Production of Hatchery-Reared Summer Flounder Paralichthys dentatus in a Marine Recirculating Aquaculture System: The Effects of Ration Level on Growth, Feed Conversion, and Survival     

Patrick M.  Carroll Wade O.  Watanabe Thomas M.  Losordo 《Journal of the World Aquaculture Society》2005,36(1):120-128

Pilot‐scale trials were conducted to evaluate growout performance of hatchery‐reared summer flounder fingerlings in a state‐of‐the‐art recirculating aquaculture system (RAS). The outdoor RAS consisted of four 4.57‐m dia × 0.69‐m deep (vol. =11.3 m³) covered, insulated tanks and associated water treatment components. Fingerlings (85.1 g mean initial weight) supplied by a commercial hatchery were stocked into two tanks at a density of 1,014 fish/tank (7.63 kg/m³). Fish were fed an extruded dry floating diet consisting of 50% protein and 12% lipid. The temperature was maintained between 20 C and 23 C and the salinity was 34 ppt. Under these conditions, growth, growth variation (CV_wt), feed utilization, and survival of fish fed to 100% and 82% of a satiation rate were compared. Due to clear changes in growth patterns during the study, data was analyzed in three phases. During phase 1 (d 1–d 196), fish showed rapid growth, reaching a mean weight of 288 g ± 105 and 316 g ± 102, with a CV_wt of 0.36 and 0.32 and FCR's of 1.38 and 1.36 in the subsatiation and satiation groups, respectively. During phase 2 (d 196–d 454), fish displayed slower growth reaching mean weights of 392 g ± 144 and 436 g ± 121, with a CV_wt of 0.37 and 0.28, and increasing FCR's of 3.45 and 3.12 in the subsatiation and satiation groups, respectively. During phase 3 (d 454–d 614), fish showed little growth reaching mean weights of 399 g ± 153 and 440 g ± 129, with a CV_wt of 0.38 and 0.29 in the subsatiation and satiation groups, respectively. Over the entire growout period (d 1–d 614), feed conversion ratios were 2.39 and 2.37 and survival was 75% and 81 % in the subsatiation and satiation treatments, respectively. The maximum biomass density reached during the study was 32.3 kg/m³. The satiation feed rate was superior to the 82% satiation rate, since it maximized growth rates, with no effect on FCR. The higher CV_wt in the subsatiation group suggests increased competition for a restricted ration led to a slower growth with more growth variation. The decrease in growth in phases 2 and 3 was probably related to a high percentage of slower growing male fish in the population and the onset of sexual maturity. This study demonstrated that under commercial scale conditions, summer flounder can be successfully grown to a marketable size in a recirculating aquaculture system. Based on these results, it is recommended that a farmer feed at a satiation rate to minimize growout time. More research is needed to maintain high growth rates through marketable sizes through all‐female production and/or inhibition of sexual maturity.  相似文献   

Critical Observations versus Physical Models for Close Binary Systems. Kam-Ching Leung, Ed. Gordon and Breach, New York, 1988. xvi, 472 pp., illus. $95. From a colloquium, Beijing, China, Nov. 1985     

Wade RA 《Science (New York, N.Y.)》1989,244(4907):994-995

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The potential use of plasma glutamate dehydrogenase activity for the evaluation of hepatic disease in the cockatiel (Nymphicus hollandicus)     

Battison AL  Buczkowski S  Archer FJ 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》1996,25(2):43-47

A reference interval for plasma glutamate dehydrogenase (GD) (E.C. 1.4.1.3) activity, of 0-8 IU/L, was established for the cockatiel (Nymphicus hollandicus). An automated modification of a commercial manual assay was used. This enzyme is considered liver specific in humans and numerous domestic animals, due to its organ distribution. A similar distribution was found in cockatiels in this study. Maximal enzyme activity was recovered from liver and kidney homogenate supernatants. Minimal activity was detected in skeletal muscle preparations. These results suggest a potential use for plasma GD activity in the evaluation of hepatocelluar injury/necrosis in cockatiels.  相似文献   

CO2 in Climate: Gloomsday Predictions Have No Fault     

Wade N 《Science (New York, N.Y.)》1979,206(4421):912-913

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Synfuels in haste, repent at leisure     

Wade N 《Science (New York, N.Y.)》1979,205(4402):167-168

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Carter plan to spur industrial innovation     

Wade N 《Science (New York, N.Y.)》1979,206(4420):800-801

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Soviets release five prisoners     

Wade N 《Science (New York, N.Y.)》1979,204(4393):598

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Doves Attack SALT II     

Wade N 《Science (New York, N.Y.)》1979,204(4400):1389

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Gilbert may leave harvard for biogen     

Wade N 《Science (New York, N.Y.)》1981,214(4520):526-527

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How to keep your shirt--if you put it in genes     

Wade N 《Science (New York, N.Y.)》1981,212(4490):26

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