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为了阐明营养盐水平下对东海原甲藻(Prorocentrum donghaiense)和米氏凯伦藻(Karenia mikimotoi)的生长特性,研究了不同营养盐总体浓度和磷限制对两种藻类生长的影响。结果表明,不同营养盐水平对东海原甲藻和米氏凯伦藻的生长影响显著,培养中期添加营养盐(二次添加)可以显著提高两种藻类的细胞浓度,同步测定氮磷营养盐水平发现,一次性添加营养盐培养时东海原甲藻对硝酸盐和磷酸盐吸收利用率分别为31.6%和76.9%,米氏凯伦藻对硝酸盐和磷酸盐的吸收利用率分别为92.5%和99.9%,二次添加营养盐培养时则稍低,同时两种藻类在实验后期较低磷酸盐水平的情况下仍然能维持较高细胞浓度,说明藻细胞内存在明显的营养盐库。在磷限制情况下,东海原甲藻和米氏凯伦藻的生长均受到明显的抑制,东海原甲藻细胞体积在磷限制培养下变化不大,而且米氏凯伦藻细胞体积在磷限制培养一段时间后明显增大,当磷酸盐恢复正常水平,细胞体积又快速恢复。该结果对于阐释不同营养盐水平下东海原甲藻和米氏凯伦藻的生长竞争机制具有一定的启示作用。 相似文献
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初始密度对微小亚历山大藻生长及产麻痹性贝类毒素的影响 总被引：1，自引：1，他引：0
为研究微小亚历山大藻生长和产麻痹性贝类毒素(PSP)的规律,采用不同初始密度对微小亚历山大藻进行培养,综合采用显微镜计数、小鼠生物检测(MBA)、高效液相色谱—柱后衍生(HPLC-FLD)等方法分析微小亚历山大藻在不同接种密度条件下的生长和产毒特性.结果表明,随着初始密度增加微小亚历山大藻通过静止期的时间缩短,到达最大生长密度的时间提前,但是生长的最大细胞密度和平均比生长率却呈下降趋势,增值模型反应的情况与观测结果相一致,随着初始密度的增加,依赖于初始种群密度的参数(a)减少,环境容量(K)减少,种群瞬时增殖速度(r)下降.4种不同初始密度(0.05×104、0.10×104、0.15×104、0.30×104cells/mL)条件下,微小亚历山大藻细胞的毒性呈现先增大后减小趋势,在初始密度为0.1×104 cells/mL条件下,同一生长期内细胞毒性比其他3个密度条件下高.HPLC检测微小亚历山大藻含有的毒素为GTX1-4,含量分别为2.14、2.08、4.97、5.04 fmol/cell.综合考虑微小亚历山大藻在生长过程中的细胞最大密度、达到最大密度所用时间以及细胞毒性大小等因数,采用(0.10～0.15)×104 cells/mL接种密度培养微小亚历山大藻,能够达到较好的产毒效果. 相似文献
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营养元素对海州湾藻类生长的影响 总被引：2，自引：0，他引：2
为了探讨营养元素对浮游植物尤其是赤潮藻类生长的影响,在海州湾近海海域采用5个圆柱形小网箱,分别一次性添加不同浓度的KH2PO4和NaNO3,诱发藻类生长的围隔实验。通过对藻类鉴定、水温、盐度、pH值和溶解氧、藻类密度、叶绿素a和营养盐（P和N）浓度的测定。结果显示：海州湾赤潮高发区浮游藻类12属19种,以弯角藻属（Eucampia）的短角弯角藻（Eucampia zoodiacus Ehrenberg）为优势种,约占整个藻类组成的80%。各实验组pH值和DO值,均有不同提高。随着KH2PO4和NaNO3浓度的增加,各实验组藻类密度和叶绿素a含量呈升高趋势,而P和N浓度逐渐降低。营养元素P和N是影响海洲湾近海岸藻类大规模增值的关键因子之一。 相似文献
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微藻生物柴油是新能源开发的热点之一.为了提高微藻作为生物柴油原料的性能,研究了接种密度对两种产油微藻(微绿球藻Nannochloropsis oculata和三角褐指藻Phaeodactylum tricornutum)生长性能及细胞油脂特性的影响.结果表明,两种微藻细胞采收密度或采收生物量与接种密度正相关,而细胞增殖效率与接种密度负相关(P＜0.05).微绿球藻和三角褐指藻细胞油脂含量随接神密度升高而降低,微绿球藻和三角褐指藻分别在接种密度为6.0×106 cell/mL和3.0×106 cell/mL时,其细胞内中性脂比例最高.微绿球藻、三角褐指藻的饱和脂肪酸(SFA)和单不饱和脂肪酸(MUFA)比例随着接种密度的提高先升高后显著下降(P＜0.05).从生产生物柴油的效率及其品质等因素综合考虑,室验条件下,培养微绿球藻适宜接种密度为6.0×106 cell/mL;三角褐指藻适宜接神密度为2.0×106 cell/mL. 相似文献
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微藻高密度培养中的生长指标和适应机制 总被引：3，自引：0，他引：3
以雨生红球藻为材料，利用5cm光径平板式光生物反应器，在室内人工光照、通气条件下，建立高密度培养体系，探讨了微藻高密度培养中的生长指标问题。结果发现，表述微藻生长的传统指标出现失真现象。如在高密度培养生物量增加时，叶绿素含量或细胞数目指标都在一定程度上与干重指标反映的生长信息相背离，甚至出现相反的变化趋势。这主要是由于随着密度增高，细胞间的互相遮蔽作用加剧，单个藻细胞所能获得的光能逐渐减少。细胞在适应光能减弱的过程中，无论藻细胞体积大小还是单个藻细胞叶绿素含量都发生了明显变化。因此，建议评估高密度体系中微藻细胞的生长状况时，应当充分地考虑高密度效应对藻细胞生物学特性的影响，从对多种生长指标的综合分析中获得正确、客观的生长信息。同时，作者还发现微藻细胞群体和个体之间存在两种完全不同的高密度适应机制，协同适应机制和争夺机制。 相似文献
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选用底栖硅藻菱形藻(Nitzschiasp.)为实验对象,分别研究了CaCl2浓度、胶珠直径、接种密度及胶珠密度对其生长的影响及后两因素对其主要营养成分含量变化的影响。结果表明:(1)随培养时间的延长,CaCl2浓度对菱形藻生长有极显著影响,在2%CaCl2溶液中形成的胶珠里菱形藻比生长速率最高;(2)胶珠直径对菱形藻在初期和指数期的生长影响显著,且较小直径(2.5～3.0mm)的胶珠较适宜菱形藻生长;(3)随接种密度和胶珠密度的提高,菱形藻的比生长速率都有先增高后下降的变化趋势,接种密度较高(2.50×104～5.50×104mL-1)时,固定化组的比生长速率是对照组的2倍左右。胶珠密度为220粒/(100mL培养液)左右较适宜(胶珠直径3.0mm);(4)初始接种密度和胶珠密度试验中,蛋白质、总糖及粗脂肪的含量固定化组低于或相当于对照组,而叶绿素的含量固定化组高于对照组。 相似文献
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在水温(22±1)℃和连续光照强度为50μmol·m~(-1)·s~(-2)下,取主要由乳酸菌、硝化菌、芽孢杆菌、光合菌,及酵母菌等组成的培藻肥水型EM菌0.5m L、2.5m L或5.0m L,分别加入到200m L密度相同的小新月菱形藻Nitzschia closterium f.、球等鞭金藻3011 Isochrysis galbana parke和小球藻Chlorella sp.中培养15d,以f培养基为对照,研究不同浓度培藻肥水型EM菌对这3种藻类生长的影响。结果表明:EM菌对金藻、硅藻、绿藻的生长都有一定的促进作用,其中对金藻及硅藻生长的促进作用更加显著,生长率提高20%~50%,最终细胞密度有所提高,添加5m L促生长作用更持久。 相似文献
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鱼类生长的幂指数生长方程 总被引：12，自引：0，他引：12
研究鱼类生长往往需要选择适当的数学模型来处理实际数据以表征生长的某些特点 ,或用于比较生长速度 ,或用于消除随机因素的影响 ,使生长曲线圆润化 ,以显示生长的趋势。其中受到高度重视并被广泛应用的是贝特朗菲方程 (ｖｏｎＢｅｒｔａｌａｎｆｆｙｅｑｕａｔｉｏｎ)。然而该模型在理论上有不足之处 ,适用范围也不够理想。为此 ,取陆文杰[1] 对林木生长研究中提出并命名的数学模型———幂指数生长方程 ,用大量的鱼类生长数据[2 -6] 验证结果 ,证实该方程比贝氏方程更适于研究鱼类生长规律。1 材料与方法1 .1 数据及其来源共 12 4份 ,75… 相似文献
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基于68个日本囊对虾(Marsupenaeus japonicus)全同胞家系,采用混合线性模型和约束极大似然法对日本囊对虾生长性状进行遗传参数的估计。结果表明:1)45日龄、75日龄体长性状的遗传力估计值分别为0.1545±0.0505、0.1933±0.0475,腹节长性状的遗传力估计值分别为0.1672±0.0473、0.1937±0.0468,体重性状的遗传力估计值分别为0.1934±0.0439、0.1992±0.037,均为中等遗传力;2)不同日龄下日本囊对虾生长性状间的表型相关与遗传相关均为高度正相关,45日龄体长–腹节长、体长–体重、腹节长–体重的表型相关为0.7121±0.0188、0.5147±0.0277、0.5052±0.0280,遗传相关为0.9896±0.00340、0.9304±0.0321、0.9429±0.0301,75日龄体长–腹节长、体长–体重、腹节长–体重的表型相关为0.6710±0.0236、0.6555±0.0181、0.6534±0.0160,遗传相关为0.7637±0.0161,0.7479±0.0148,0.7177±0.0131。本研究表明对日本囊对虾生长性状进行选择是有效的,以体长、腹节长、体重任一性状作为指标进行选育均可达到生长改良的目的,本研究结果可为日本囊对虾的早期选择育种和多性状选择提供数据参考。 相似文献
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Three approaches for multivariate analysis of fish growth in aquaculture experiments with Nile tilapia (Oreochromis niloticus niloticus L.) based on the von Bertalanffy growth curve are presented and compared. The approaches are: an extended Gulland‐and‐Holt (GH) plot, a forced extended GH plot and a multilinear regression analysis for the growth parameter K. All three models provide valuable insight into the major environmental factors influencing the daily growth rate and explain 28–46% of the variance of the observed daily growth rate of the used data set. For all three methods, the modelled parameter is significantly related to the net yield of Nile tilapia and can, therefore, be used for the predictive modelling of management scenarios. The extended GH plot loads the influence of environmental parameters upon L∞, while the forced extended GH plot and Direct fitting of K load the influence on the growth parameter K. The latter is more in the tradition of aquaculture research. But the forced extended GH plot and Direct fitting of K can only be applied if L∞ of the cultured species is known, as the selected L∞ influences the variance in the regression variables. 相似文献
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采用原位光密度法探讨三十烷醇（TA）、吲哚乙酸（IAA）和赤霉素（GA3）对咖啡形双眉藻（Amphora coffeaeformis)和灰状舟形藻（Navichla corymbosa)生长速率的影响。单因子试验结果表明，3种植物生长激素对2种底栖硅藻生长速率均有显著的促进作用（P＜0．05）。其中IAA和GA3对2种底栖硅藻的最佳质量浓度均为0．5mg/L，TA对咖啡形双眉藻的最佳质量浓度为1．0mg/L，对灰状舟形藻的最佳质量浓度为0．1mg/L，正交多因子试验结果表明，培养2种底栖硅藻的TA、IAA和GA3最佳质量浓度（mg/L），配比分别为：咖啡形双眉藻0．5：0．5：0．5；盔状舟形藻0．1：0．05：1．0。 相似文献
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Compensatory growth in fishes: a response to growth depression 总被引：15，自引：0，他引：15
Compensatory growth (CG) is a phase of accelerated growth when favourable conditions are restored after a period of growth depression. CG reduces variance in size by causing growth trajectories to converge and is important to fisheries management, aquaculture and life history analysis because it can offset the effects of growth arrests. Compensatory growth has been demonstrated in both individually housed and grouped fish, typically after growth depression has been induced by complete or partial food deprivation. Partial, full and over‐compensation have all been evoked in fish, although over‐compensation has only been demonstrated when cycles of deprivation and satiation feeding have been imposed. Individually housed fish have shown that CG is partly a response to hyperphagia when rates of food consumption are significantly higher than those in fish that have not experienced growth depression. The severity of the growth depression increases the duration of the hyperphagic phase rather than maximum daily feeding rate. In many studies, growth efficiencies were higher during CG. Changes in metabolic rate and swimming activity have not been demonstrated yet to play a role. Periods of food deprivation induce changes in the storage reserves, particularly lipids, of fish. Apart from the strong evidence for the restoration of somatic growth trajectories, CG is a response to restore lipid levels. Although several neuro‐peptides, including neuropeptide‐Y, are probably involved in the control of appetite, their role and the role of hormones, such as growth hormone (GH) and insulin‐like growth factor (IGF), in the hyperphagia associated with CG are still unclear. The advantages of CG probably relate to size dependencies of mortality, fecundity and diet that are characteristic of teleosts. These size dependencies favour a recovery from the effects of growth depression if environmental factors allow. High growth rates may also impose costs, including adverse effects on future development, growth, reproduction and swimming performance. Hyperphagia may lead to riskier behaviour in the presence of predators. CG's evolutionary consequences are largely unexplored. An understanding of why animals grow at rates below their physiological capacity, an evaluation of the costs of rapid growth and the identification of the constraints on growth trajectories represent major challenges for life‐history theory. 相似文献
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The effects of temperature on the survival, growth rate and growth efficiency of larval and juvenile common wolffish, Anarhichas lupus L. were studied at 0–31 days and 9–12 months post-hatching, respectively. The influence of temperature regime during egg incubation on subsequent survival and growth was also examined. The fish were reared at constant water temperatures of 5, 8, 11 and 14°C, and all groups were fed dry pellets. At age 1 month, maximum growth rates were observed at 11 and 14°C. Growth rates and survival of early juveniles were dependent upon incubation history, high growth being obtained only if rearing temperature exceeded the temperature of egg incubation. In juveniles at age 9–12 months, the relationships between temperature and growth, and temperature and growth efficiency were parabolic: the optimum water temperatures for growth (Topt.G) and growth efficiency (Topt.GE) were 11°C and 9.7°C respectively. The growth rate and growth efficiency at these water temperatures were 0.9% day–1 and 0.45 g weight gain per g food offered, respectively. © Rapid Science Ltd. 1998 相似文献
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Shunsuke Moriyama Katsuo Tashiro Suehiro Furukawa Hiroshi Kawauchi 《Fisheries Science》2008,74(4):860-866
ABSTRACT: The ability of salmon growth hormone (sGH) to accelerate the somatic growth of juvenile abalone Haliotis discus hannai by immersion was examined. After immersion for one hour into a sGH-rich solution at a concentration of 30 mg/L, the sGH immunoreactivity in the body fluid of abalone was maximal after one day, and levels were still detectable at two days. No immunoreactivity was observed in the control group. Following immersion for one hour at one or two-week intervals for 120 weeks into the sGH-rich solution at 30 mg/L, the sGH-immersed abalone exhibited a significant increase in shell length and body weight. On the other hand, abalone immersed into a salmon prolactin (sPRL)-rich solution at 30 mg/L for one hour showed a lower increase in both shell length and body weight than the sGH-immersed abalone. No increases in shell length and body weight were observed in either the bovine serum albumin-immersed abalone or untreated controls. These results provide evidence that sGH can be transported from ambient water into the circulatory system of abalone, and can subsequently improve the somatic growth of juveniles. 相似文献
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为深入了解生长轴(GH/IGF axis)对半滑舌鳎(Cynoglossus semilaevis)生长发育的调控作用,采用定量PCR方法研究了GH/IGF轴5个关键生长因子(GH、GHR1、GHR2、IGF-I、IGF-II)在配子、胚胎发育和仔稚幼鱼生长过程中的差异表达调控特性。结果显示,这5个生长因子都具有亲本遗传的特性,除GH外,精子中其他4个生长因子转录表达水平均显著高于卵子。在胚胎发育阶段, GH mRNA在胚胎发育各时期均有表达,且在细胞分裂初期和孵化期表达水平较高。GHR1和GHR2mRNA在胚胎发育各时期呈现相似的表达水平变化趋势,除囊胚期和原肠胚期外, GHR1 mRNA的表达量均高于GHR2。IGF-I和IGF-II mRNA在胚胎发育各时期均表达, IGF-I在孵化期表达水平最高, IGF-II在胚体下包2/3期和孵化期表达水平最高。除64细胞期和128细胞期外, IGF-II mRNA的表达量均显著高于IGF-I (P0.05)。在仔稚幼鱼生长阶段, GH mRNA表达水平从孵化后3 d开始显著升高,到6 d时达峰值。GHR1 mRNA表达水平自6 d开始显著升高(P0.05),到30 d达峰值。GHR2 mRNA在3 d、20 d、25 d、30 d和60 d均处于显著高表达水平(P0.05)。IGF-I mRNA在3 d表达水平最高, IGF-II mRNA从6 d开始显著上调表达,并保持较高表达水平至45 d, IGF-II mRNA表达量均显著高于IGF-I (P0.05)。偏相关分析发现:这5个生长因子通过正向协同或负向拮抗作用在半滑舌鳎胚胎发育和仔稚幼鱼生长过程中共同起调控作用。研究结果为深入了解GH/IGF轴对鱼类生长调控机制积累了新的素材。 相似文献
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采用黑鲷生长激素(seabream growth
hormone,brGH)放射免疫测定法(brGHRIA)及黑鲷生长激素放射受体测定法(brGHRRA)，研究了不同季节(3月、6月、9月及12月)黑鲷血清GH水平及肝脏和性腺中生长激素
受体(growth hormone receptor,GHR)水平的变化，同时测定了黑鲷白肌及肝脏RNA-DNA比率及黑鲷肥满度
(condition factor,K)和性腺指数(gonadosomatic 相似文献