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A 60-day feeding experiment was conducted to investigate the influence of dietary omega-3 long-chain polyunsaturated fatty acids(n-3 LC-PUFA) on growth, nutritional composition and immune function of marine fish Sebastiscus marmoratus. Five diets containing 3.6, 10.2, 18.2, 26.5, or 37.0 g/kg n-3 LC-PUFA were prepared. The results reveal significant influences of dietary n-3 LC-PUFA on the final weight, weight gain, specific growth rate, feed conversion ratio, and condition factor. As dietary n-3 LCPUFA increased, weight gain and specific growth rate increased and were significantly higher in groups fed 18.2, 26.5 and 37.0 g/kg than in groups fed 3.6 and 10.2 g/kg( P 0.05); there was no significant difference between groups fed 18.2, 26.5, or 37.0 g/kg( P 0.05). With increasing dietary n-3 LC-PUFA, eicosapentaenoic acid and docosahexenoic acid content in muscle and liver increased significantly, immunoglobulin class M content gradually increased from 9.1 to 14.8 μg/L, and lysozyme activity content increased from 1355 to 2268 U/mL. Broken line model analysis according to weight gain indicated that a dietary n-3 LC-PUFA level of 18.2 g/kg is essential for normal growth at a fat level of 125 g/kg. Therefore, appropriate dietary n-3 LC-PUFA not only promote growth and improve the n-3 LC-PUFA content, but also enhance immune function in S. marmoratus. 相似文献
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中子法测量土壤含水量具有测量不用取样、测速快、精确度高、测深不限的优点 ,在非饱和水的测量及动态观测方面 ,有着独特的作用。烘干法是最基本最常用测量方法 ,也是其它测量方法的参照标准。本实验分析比较了两种测量方法的精度 ,其结论对中子土壤水分仪使用者有一定的参考作用。 相似文献
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利用线粒体细胞色素 c 氧化酶Ⅰ亚基(COI)部分序列研究了南海区鲳属鱼类(Pampus)银鲳(P. ar-genteus)、珍鲳(P. minor)和中国鲳(P. chinensis)的系统进化与种群遗传结构.通过 PCR 扩增与序列测定获得了长度为643 bp 的 COI 基因片段,其 A、T、G、C 碱基的平均含量分别为25.4%、33.6%、18.9%和22.1%, A+T 含量高于 G+C 含量.64条序列共定义了20种单倍型,包含152个变异位点,简约信息位点148个,单变异位点4个,产生169个点突变.结果表明,银鲳与中国鲳的遗传差异最小,银鲳与珍鲳的其次,而珍鲳与中国鲳的遗传差异最大,3种鲳属鱼类的遗传多样性均呈现较低的水平,应采取有效的保护措施,以避免其遗传多样性水平的进一步丧失.本研究结果为鲳属鱼类资源保护和合理开发利用提供必要的参考 相似文献
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为揭示不同抗流能力的大黄鱼(Larimichthyscrocea)肌肉基因表达水平的变化,筛选抗流相关基因,解析大黄鱼抗流性状形成的分子基础,收集福建福鼎沙埕湾主养区1 000尾大黄鱼,在设计制作的抗流实验水槽中,以流速1.0m/s为筛选条件,将抗流时间>30 min的大黄鱼归为抗流组(HM组),抗流时间<5 min的大黄鱼归为非抗流组(SM组),对其肌肉进行转录组分析,并统计抗流分组后48 h内大黄鱼的累计死亡率。转录组结果显示, HM组与SM组文库共富集到1806个差异表达基因(DEGs),其中1090个上调,716个下调。GO功能注释发现显著富集的条目主要集中在肌肉收缩相关功能, KEGG富集分析发现上调的DEGs主要富集在心肌收缩、氧化磷酸化、黏着斑、ECM-受体相互作用、AGE-RAGE、MAPK、心肌细胞中的肾上腺素能等相关通路;下调的DEGs主要富集在真核生物核糖体的发生、蛋白酶体、内质网中的蛋白加工、RNA转运、泛素介导的蛋白水解信号通路等。此外,RT-qPCR结果表明,随机选取的DEGs与RNA-seq结果的表达趋势一致。48h的累计死亡率结果显示,SM组... 相似文献
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盐度对银鲳(Pampus argenteus)Na /K -ATP酶活力及血清渗透压调节激素浓度的影响 总被引：1，自引：0，他引：1
采用检测银鲳(Pampus argenteus)幼鱼鳃Na+/K+-ATP(NKA)酶活力、血清生长激素(GH)、胰岛素样生长因子Ⅰ(IGF-Ⅰ)和催乳素(PRL)浓度的方法, 研究了不同盐度下银鲳渗透压调节机制。结果表明, 鳃NKA酶活力在三种盐度下总体呈先上升后恢复的变化, 其最高点为14盐度48h时, 且显著高于其它值(P<0.05)。36盐度组的血清GH浓度显著高于其它组(P<0.05)。盐度变化均使血清IGF-Ⅰ浓度呈现先上升后恢复的变化。14盐度组血清催乳素浓度始终高于其它各盐度组。在低盐度适应(14和25)时, 血清GH浓度与NKA酶活力呈极显著正相关(P<0.01); 高盐度适应(36和25)时, 血清催乳素浓度与NKA酶活力呈显著负相关(P<0.01)。另外, 血清催乳素与IGF-Ⅰ浓度间有极显著正相关(P<0.01)。研究证明银鲳幼鱼在适应不同盐度时, 鳃NKA酶、生长激素、IGF-Ⅰ和催乳素在渗透压调节中起着重要作用, 并且相互之间存在一定关联。 相似文献
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将点带石斑鱼的受精卵置于不同盐度的水体中,观察受盐度胁迫下点带石斑鱼胚胎的沉浮 情况、卵径、油球径、孵化率、畸形率,以及卵黄囊仔鱼的形态变化和营养物质的消耗状况.结果 表明,点带石斑鱼受精卵在盐度25(含25)以下的水体中为沉性,在盐度35(含35)以上的海水中全部 漂浮于水表层,在盐度30和对照组31的水体中大部分胚胎浮在水上层.受精卵卵径随孵化盐度降低而减小.在水温26-28℃的条件下,点带石斑鱼受精卵经21-26h可孵化成仔鱼,盐度对孵化时间影响不显著(P>0.05).盐度在15-50范围内都能孵出仔鱼,但孵化率和畸形率因盐度不同而有显著差异.综合分析表明点带石斑鱼受精卵孵化的适合盐度范围为26.7-41.1.最适孵化盐度范围在30.5-32.5之间.盐度对卵黄囊仔鱼可量性状的影响主要表现在卵黄囊容积和全长的变化,高盐度(≥45)下胚后仔鱼卵黄囊容积、全长和体高显著减小(P<0.05),油球径不因盐度不同而改变. 相似文献
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Juvenile silver pomfret, Pampus argenteus, was grown in culture tanks for 9 weeks on four different diets, and their effects on fish growth, digestive enzyme activity, and body composition were assessed. The feeding regime was as follows: Diet 1: fish meat; Diet 2: fish meat+artificial feed; Diet 3: fish meat+artificial feed+Agamaki clam meat; Diet 4: fish meat+artificial feed+Agamaki clam+copepods. The greatest weight gain was associated with Diet 4, while the lowest weight gain was associated with Diet 1. No significant difference was observed in weight gain between fish receiving Diet 2 and Diet 3. Specific growth rate followed similar trends as weight gain. The feed conversion ratio (FCR) of fish fed Diet 1 was significantly higher than the other fish groups, but no significant differences were observed in FCRs of fish fed Diet 2, Diet 3 or Diet 4. There was also no significant difference in the hepatosomatic index (HSI) between the four diets. For fish that received Diets 2-4, containing artificial feed, higher protease activities were detected. A higher lipid content of the experimental diets also significantly increased lipase activities and body lipid content. No significant differences in amylase activity or body protein content were found between Diets 1-4. In conclusion, a variety of food components, including copepods and artificial feed, in the diet of silver pomfret significantly increased digestive enzyme activity and could improve growth performance. 相似文献
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根据mtDNA D-loop 序列分析东海银鲳群体遗传多样性 总被引：3，自引：1，他引：2
根据线粒体D-loop序列对舟山群岛附近海域的银鲳(Pampus argenteus)群体(n=24)的遗传多样性进行了研究。通过PCR技术对线粒体D-loop序列进行扩增,获得大小约为500bp的扩增产物。PCR产物经纯化并进行序列测定后,得到了357bp的核苷酸片段。在24个个体中,共检测到14个变异位点,其中8个转换位点,5个颠换位点,1个转换与颠换同时存在的位点。运用MEGA软件计算出不同个体间的遗传距离,并根据其遗传距离构建了UPGMA和NJ系统树。DNASP软件计算出的单倍型多样性(h)、核苷酸多样性(π)及平均核苷酸差异数(k)分别为0.89、0.007与2.57。此外,岐点分布及中性检验显示,东海银鲳群体在历史上可能经历过种群扩张。研究结果表明,线粒体D-loop基因可用于银鲳群体内及群体间遗传多样性的分析。 相似文献
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