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41.
采用花生四烯酸即廿碳四烯酸(AA, 20∶4n-6)含量梯度法,制备了四种n-3HUFA含量相等、DHA/EPA比例相同、AA含量分别为0.06%、1.00%、1.5%、2.0%的实验微粒饲料,进行了AA的不同含量对牙鲆仔稚鱼生长、存活、体内相关成分以及对外部压力耐受性的影响研究.26天的养殖试验结果表明,当牙鲆仔稚鱼实验微粒饲料中AA的含量为1.5%时,牙鲆仔稚鱼的生长、存活以及对不同压力的耐受性都达到最佳.养殖试验结束后,对稚鱼体内相关成分的分析结果表明,稚鱼体内AA的含量随着实验微粒饲料中AA含量的增加而增加.  相似文献   
42.
不同放养密度和混养石莼对牙Ping鱼种生长的影响   总被引:1,自引:0,他引:1       下载免费PDF全文
牙鲆的放养密度以所放养鱼腹面表面积之和占养殖池底面积的百分数 ( % )表示。在直径为27cm、容积为40L的塑料桶中放置网箱 ,按网箱底面积48 % ,74 %或100 %的密度放养牙鲆 (Paralichthysolivaceus)幼鱼 (体质量1.86g±0.18g,全长6.3cm±0.27cm)。同时另在放养密度100%组中混养石莼40.00g。经45d饲养 ,混养石莼组中的牙鲆生长最快 ,水质好 ,饲养系数最低。在单养组中 ,牙鲆生长速度由快至慢依次为48 %组>74%组>100%组。牙鲆体长增长和体质量增长速度最快的密度分别为80 %~100%和100%~110 % ,低于或高于此密度鱼的增长均减慢。  相似文献   
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The in vitro acute cytotoxicity of the neonicotinoid insecticide acetamiprid to FG cell line, derived from the gill of flounder Paralichthys olizaceus, was tested by the three widely used endpoint bioassays-neutral red (NR) assay, tetrazolium (MTT) assay and cell protein assay. It was found that acetamiprid was increasingly toxic to FG cells at concentrations of 1 μg/cm^3 or above, and the inhibitory concentration 50% values for NR, MTF, and cell protein assays were 38.38, 36.27 and 32.03 μg/cm^3, respectively. This appeared to be the first report on the in vitro cytotoxicity of acetamiprid to non-mammalian vertebrate cells. Ultrastructural examination revealed that for the cells exposed to 60 μg/cm^3 acetamiprid for 48 h, their mitochondria were severely damaged with the cristae swelled up or disrupted, while their nuclei and rough endoplasmic reticlum (RER) appeared to be still normal. This suggests that mitochondria are possibly the primary target of acetamiprid.  相似文献   
44.
Prey availability is one of the most important factors affecting the quality of nursery grounds. Estuaries play an important role as nursery grounds for juvenile stone flounder, but the mechanism behind the consistently high availability of prey has never been examined. This study investigates which prey is mainly selected by juvenile stone flounder (15–55 mm standard length) in the estuary of the Natori River, northern Japan. In a cage experiment, juveniles showed positive selection for the palps of the spionid polychaete Pseudopolydora kempi in March, and for the siphons of the bivalve Nuttallia olivacea in April, May and June in both sandy and muddy-sand habitats. This selective predation showed that sublethal predation on regenerable parts of invertebrates is important for stone flounder. Nuttallia olivacea, the dominant bivalve in the estuary, was more abundant and in better somatic condition in the sandy area in spite of the stronger siphon-cropping pressure by juvenile stone flounder. These results confirm that sublethal predation on highly abundant benthos plays an important role in forming estuarine habitats into areas of high prey availability for juvenile stone flounder, which leads to their high growth rate.  相似文献   
45.
The FG-9307 cell line derived from the gill of flounder Paralichthys olivaceus was used in the present study to determine the acute cytotoxic effects of the organophosphorous pesticide, profenofos. It was found that the cell growth rate was markedly reduced by profenofos at the concentrations of 2.5, 5 and 7.5 mg/L tested; and that the fine structures of the cells were also altered by profenofos, as evidenced by dilation of nuclear membranes and mitochondria cristae, and presence of enlarged lysoscrneswith engulfed organelles and numerous vacuoles in the cytoplama. Probably, mitochondria, the cell ener-gy-generating sites, are the most prcrninent sites of profenofos cytotoxity in the cells. This seems to be the first report of the use of marine fish cell line for evaluation of the acute in vitro cytotoxicity of organophos-phorus pesticide.  相似文献   
46.
INTRODUCTIONPollutionofmarineecosystemposesaseriousthreattomarineorganismsandultimatelytheentireecosystem.Inrecentyears,organophosphorous(OP)pesticideshavelargelyreplacedorganochlorinepesticidesbecauseoftheirrapidbreakdowninwaterandtheirlowenvironmenta…  相似文献   
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在实验室塑料水槽中,观察了不同盐度条件下星斑川鲽(Platichthys stellatus)幼鱼(10.6±0.27g)的存活率,摄食和生长状况。结果表明:将星斑川鲽幼鱼从盐度为32的海水中直接移入低盐水中,在各个盐度下96h后存活率均为100%;经盐度驯化后42d的各组鱼成活率也为100%。盐度0,8,16组的增重率和特定生长率高于24和32组;摄食率32时最高,16时最低;饵料转化效率16时最高24时最低,各组间差异不显著(P>0.05)。另外实验表明低盐度有利于星斑川鲽白化病的康复。  相似文献   
50.
针对我国鲍与牙鲆工厂化养殖普遍存在的设施配套标准差、养殖容量低、生产成本高、病害日趋严重等问题,提出了工厂化养殖设施适应性技术改造的主要技术措施要点。  相似文献   
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