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Travis J 《Science (New York, N.Y.)》1994,264(5161):906
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Travis J 《Science (New York, N.Y.)》1994,264(5166):1668
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Travis J 《Science (New York, N.Y.)》1995,267(5205):1768-1769
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Observations on growth, sexual maturity and spawning performance of pond-reared Penaeus merguiensis 总被引:2,自引:0,他引:2
This 12‐month preliminary study investigated the development of sexual characters, primary sexual maturity, ovarian maturity and spawning performance of pond‐reared Penaeus merguiensis in relation to culture conditions in south‐east Queensland, Australia. Post‐larvae of P. merguiensis were produced and cultured in two 60‐m3 tanks during the first 14 weeks. Before winter, they were harvested and stocked in three different overwintering facilities: a 200‐m2 covered pond, two 60‐m3 outdoor tanks and a 15‐m3 indoor, recirculated tank at a stocking density of 10 individuals m?2. The development of sexual characters was found to be similar to that reported previously in wild P. merguiensis. Males matured at younger ages and smaller sizes than females. Overall, the average size at primary sexual maturity of pond‐reared P. merguiensis was 23.1 mm carapace length for males (possessed spermatophores) and 29.3 mm for females (being impregnated). Water temperature and the availability of natural food strongly influenced prawn growth, maturity rate and their subsequent spawning performance. Growth, maturity rate and spawning performance of prawns in the covered pond were significantly higher than in the other overwintering facilities. Prawns started mating at 6–7 months, reached full ovarian maturation and spawned as early as about 8 (peaked at 9–11) months from hatching, producing high fecundity and viable larvae. There was a strong relationship (P < 0.001) between prawn size and fecundity. The results of this study suggest a potential for using pond‐reared broodstock P. merguiensis for hatchery production and for domestication or selective breeding programmes. 相似文献
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Snyder Marcía N. Schumaker Nathan H. Ebersole Joseph L. Dunham Jason B. Comeleo Randy L. Keefer Matthew L. Leinenbach Peter Brookes Allen Cope Ben Wu Jennifer Palmer John Keenan Druscilla 《Landscape Ecology》2019,34(5):1197-1197
Landscape Ecology - In the original publication of the article, the third author name has been misspelt. The correct name is given in this Correction. The original version of this article was revised. 相似文献
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Relationship of vulvar swelling to estrus in mink 总被引:1,自引:0,他引:1
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Mink with Aleutian disease developed severe anemia within a few months after infection. Evaluation of erythropoiesis and erythrocyte survival demonstrated that the anemia was caused by increased erythrocyte destruction, complicated in some cases by decreased or inadequate erythropoiesis. An inverse relationship existed between the amount of IgG on affected mink erythrocytes and the erythrocyte half-life. However, the number of IgG molecules/erythrocyte were not high enough to be detected by direct Coombs' test, with the exception of one case. Inadequate erythropoiesis was reflected by lower plasma iron turnover levels and reticulocyte numbers than expected considering the severity of the anemia involved. 相似文献