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Morales-Nin B Geffen AJ Cardona F Kruber C Saborido-Rey F 《Marine pollution bulletin》2007,54(11):1732-1741
Juvenile turbot (Scophthalmus maximus) were kept in captivity and were fed a prepared food contaminated with five different concentrations of seawater-accommodated fuel oil from 2.4+/-0.35 to 48.2+/-2.2 mg g(-1) food, with a control group receiving uncontaminated food. The growth and survival of individually tagged fish (N=202) were measured after a six-week treatment period. The otolith growth rate was measured and otolith composition was determined before and after the treatments using LA-ICPMS. Fish and otolith growth were negatively affected by the fuel oil treatment, and the response decreased with the level of contamination. Otolith growth and element incorporation peaked at mid level exposures and decreased at the highest level. The otolith elemental composition reflected the presence of some elements in the Prestige fuel that may have been incorporated through the diet into the otolith. 相似文献
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Ovaries of Baltic sprat (Sprattus sprattus balticus S.) were analysed histologically to identify stages of postovulatory follicles (POF) and to assess the oocyte development pattern. Samples were taken every 3 h during a 24 h trawl survey conducted in the Bornholm Basin in April 2007. Gonad histology revealed spawning of sprat throughout the day which hampered the exact ageing of POFs by the postovulatory follicle method and therefore did not allow direct estimation of spawning frequency. However, it was possible to define four stages of POFs, according to their histological features. The occurrence of these POF stages (I to IV) corresponded clearly to the development of the leading oocyte cohort. Further, the oocyte recruitment pattern revealed that the spawning batch can be identified prior to hydration. The POF stages I and II were present almost exclusively in vitellogenic ovaries, POF III were found in ovaries in the germinal vesicle stage, and the most deteriorated POF stage IV was found in actively spawning fish with hydrated oocytes. Since POF were absent only in very few ovaries (5%), and in each ovary in general only one POF stage was present, the duration of POF degeneration approximately equals the average batch interval, i.e. the time lag between subsequent spawning events. The results of the present study will serve as basis for future studies on Baltic sprat oocyte recruitment and daily spawning fraction. 相似文献
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