微绿球藻的培养及保存技术

本文论述了在海水苗种生产中被大家称为海水小球藻的微绿球藻,在细胞大小、形态、色素组成上等与小球藻的差异,阐述了有关微绿球藻的培养方法、藻种分离及保存方法以及微绿球藻的营养、饵料生物价值。文末,对微绿球藻今后的应用前景进行了展望。     

氮浓度对海绿球藻生长及总脂含量的影响

用叶绿素荧光分析技术和生物化学方法,研究了不同氮浓度[0.22、0.44、0.66、0.88mmol/L(对照组)]对海绿球藻叶绿素荧光特性、细胞密度、叶绿素含量、相对生长率、干质量、总脂含量及总脂产率的影响。试验结果表明,第4～7d,0.22mmol/L处理组的主要荧光参数(光系统Ⅱ的最大光能转换效率Fv/Fm,光系统Ⅱ的潜在活性Fv/Fo,相对电子传递效率rETR,光系统Ⅱ的实际光能转化效率ΦPSⅡ)显著低于其他处理组。该藻的细胞密度、叶绿素a、b含量、相对生长率及干质量随起始氮浓度的增加而增加,0.22mmol/L处理组上述各项值最低,0.88mmol/L对照组上述各项值最高,其细胞密度、相对生长率和干质量分别为16.37×106个/ml,0.56、0.48g/L。0.22mmol/L处理组总脂含量(占干质量的41.84%)显著高于其他处理组,而对照组总脂含量仅为35.16%。总脂产率与起始氮浓度成正相关,0.22mmol/L处理组最低,仅为0.0095g/(L.d),而0.88mmol/L对照组总脂产率最高,为0.0189g/(L.d)。研究结果表明,氮浓度为0.22mmol/L最适合海绿球藻油脂的积累;氮浓度为0.88mmol/L最适合海绿球藻的生长。     

光照、温度、碳源及接种密度对微绿球藻生长的影响

运用正交设计法开展了碳源和接种密度,光照、温度和接种密度对微绿球藻生长影响的试验。结果表明,在碳源和接种密度的试验中,NaHCO_3浓度、接种密度及其交互作用存在显著性差异,最优水平为NaHCO_32.5g/L、接种密度300×10~4个/mL。在光照、温度和接种密度试验中,各因子以及其一级交互作用均存在着显著性差异,最优水平是培养温度30±1℃、光强7000LX、接种密度100×10~～150×10~4个/mL。     

新月菱形藻的光生物反应器半连续培养

利用平板式光生物反应器对新月菱形藻进行半连续培养,探讨更新率、更新周期对新月菱形藻生长、细胞采收量、生化成分及细胞生物量产率的影响.结果显示,随更新率的增大,新月菱形藻的生长速率增大,藻液中氮磷的平均含量上升,而平均细胞密度及产率呈下降趋势;总采收量与更新率呈抛物线关系,细胞生物量、胞内多糖和蛋白的最大采收量分别收获于33%、25.2% 和34.7%的更新率下,其最大值分别为2.11×1012 cell、3623 mg 和2347 mg.更新周期的延长导致新月菱形藻平均生长速率减小,藻液中氮磷的平均含量下降,而采收的平均细胞密度与产率增大,胞内代谢物蛋白质和多糖的含量增加;总细胞采收量随着更新周期的延长减小,当更新周期为1 d时采收量最大,为3.12×1012 cell.综合考虑,更新率为33%、更新周期为1 d,是收获生物量的最佳条件.     

不同生长阶段微绿球藻的营养价值

微绿球藻(Nannochloropsis oculata)是一种重要的海产经济微藻,易培养,是海产苗种生产中广泛应用的一种饵料微藻。在澳大利亚及以色列等国家,微绿球藻被规模化培养来用于生产高纯度的EPA。微藻的营养价值取决于藻种的遗传因素、生长阶段和培养条件。有关培养条件对微藻营养、脂肪酸组成的影响报道较多,而关于生     

拟微绿球藻粉替代鱼粉对大菱鲆幼鱼生长性能、体组成和血清生化指标的影响

为探讨拟微绿球藻(Nannochloropsis sp.)粉替代鱼粉对大菱鲆(Scophthalmus maximusL.)幼鱼生长性能、体组成和血清生化指标的影响,用拟微绿球藻粉替代基础饲料中0%、3.88%、7.76%、11.64%和15.52%的鱼粉,配制成5种等氮等能的饲料(N_0、N_(3.88)、N_(7.76)、N_(11.64)、N_(15.52))。选取初始体重为(24.60±0.02) g的大菱鲆幼鱼600尾,随机分成5组,每组3个重复,每个重复40尾鱼,养殖周期70d。结果显示:1)各实验组大菱鲆幼鱼的增重率(WGR)、特定生长率(SGR)、蛋白质效率(PER)、饲料系数(FCR)、日摄食率(DFI)、肥满度(CF)和成活率(SR)均无显著差异(P0.05);2)随着藻粉添加量的增加,全鱼及肌肉中粗脂肪含量显著降低(P0.05),粗蛋白、粗灰分和水分含量无显著差异(P0.05);3)血清溶菌酶(LZM)、补体蛋白C3、补体蛋白C4及酸性磷酸酶(ACP)活力均呈先上升后下降的趋势,分别在N_(7.76)、N_(7.76)、N_(11.64)、N_(7.76)组达到最大值,且显著高于N_0组(P0.05),N_(15.52)组碱性磷酸酶(ALP)显著低于其他组(P0.05),其他组之间无显著差异(P0.05);4)藻粉组血清总超氧化物歧化酶(T-SOD)、总抗氧化能力(T-AOC)和谷胱甘肽过氧化物酶(GSH-PX)活力,均呈先上升后下降的趋势,在N_(7.76)组达到最大值,且显著高于N_0组(P0.05);5) N_(7.76)组血清甘油三酯(TG)含量显著低于其他组(P0.05),其他组之间无显著差异(P0.05),藻粉组血清总胆固醇(TCHO)显著低于N0组(P0.05),各藻粉组之间差异不显著(P0.05);6)藻粉组血清谷草转氨酶(AST)活力呈先下降后上升的趋势,N_(11.64)组达到最小值,显著低于N_0组(P0.05),藻粉组谷丙转氨酶(ALT)活力显著低于N_0组(P0.05)。研究表明,本实验条件下,拟微绿球藻粉替代大菱鲆幼鱼饲料中15.52%的鱼粉对其生长无显著影响,替代7.76%可显著提高其非特异性免疫力,降低血脂水平。     

不同浓度的Cd~(2+)、氮及其交互作用对小球藻和微绿球藻生长及叶绿素荧光特性的影响

研究了不同的Cd2+浓度与氮浓度交互作用对小球藻和微绿球藻生长及叶绿素荧光特性的影响。结果表明,Cd2+浓度、氮浓度、胁迫时间及三者的交互作用对小球藻和微绿球藻的生长及光合作用均具有显著影响(P<0.05),其中Cd2+浓度对2株微藻的Fv/Fm(光系统Ⅱ的最大光化学量子产量)和Yield(光系统Ⅱ的实际光能转化效率)影响最显著,氮浓度对2株微藻的NPQ(非光化学淬灭)和微绿球藻的qP(光化学淬灭)影响最显著。相关性分析结果表明,2株微藻的细胞密度、叶绿素相对含量及部分荧光参数(Fv/Fm和Yield)均与Cd2+浓度呈显著的负相关关系。在低氮(55μmol/L)条件下,小球藻和微绿球藻的荧光参数Fv/Fm、Yield和NPQ均有明显下降,细胞密度和叶绿素相对含量也均有不同程度的降低。小球藻的Fv/Fm和Yield在高氮(7040μmol/L)和低浓度Cd2+条件下,下降幅度小,表现为拮抗作用。试验还发现,在低氮和高氮条件下,高浓度Cd2+对小球藻的胁迫作用加强,表现为协同作用。微绿球藻在高氮条件下,其处理组间荧光参数差别不明显,表现为拮抗作用。     

小新月菱形藻生长条件及半连续培养条件研究

为研究温度、光照和营养盐对小新月菱形藻生长的影响,设计了5个温度,3个光照度,各种营养盐各4个浓度以及6个更新率,进行了小新月菱形藻的培养试验。结果表明:小新月菱形藻的最佳生长温度为15～20℃,最佳光照度为5000 lx,氮、磷、硅、铁的最佳浓度依次为300、15、120、1.575 mg/L;当温度高于30℃或者光照度大于10000 lx时,小新月菱形藻均不能生长。对小新月菱形藻进行半连续培养条件的研究发现,小新月菱形藻在6个不同的更新率(25%、30%、35%、40%、45%和50%)条件下均能完成半连续培养。根据不同更新率下的细胞密度和实际生产中的培养密度,建议采收率在40%～45%。     

反应器培养眼点拟微绿球藻时摆向、光程对产量的影响

在内蒙古达拉特旗地区(N 40°,E 110°)户外自然条件下利用板式反应器培养眼点拟微绿球藻并进行产量研究。通过对9、11、13、17cm光程反应器对比,确定13cm光程反应器养殖产量最高,并在存在反应器间距的情况下,得到13cm光程反应器南北摆放时单位占地面积产量要高于反应器东西摆放时单位占地面积产量,从6月到8月分别高16.3%、8.7%和3.0%。同时本研究给出可根据养殖当地的地理位置,预测反应器的摆放方向以及反应器间距等参数设置的方法,以获得养殖产量的最大值。     

接种密度对产油微绿球藻和三角褐指藻生长及油脂性能的影响

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.     

The effect of light intensity on the growth of Brachymystax lenok (Pallas, 1773)

A 35‐day experiment was carried out to investigate the effect of light intensity on growth of Brachymystax lenok under different light intensities: 10, 70, 240 and 1000 lx. Fish(5.5 ± 0.24 g)used in the experiment were fed to satiation twice a day (08:00 hours, 14:00 hours).The photoperiod was 12L:12D (08:00–20:00 hours). The specific growth rate(SGR) of B. lenok under lower intensities(10 lx,70 lx)was significantly higher than the other groups(P < 0.05).No significant difference in feed intake was observed at different light intensities, but feed efficiency (FE) in wet weight at lower intensities (1070 lx) was higher than that at higher intensities(240,1000 lx) (P < 0.05).The final survival rate of juveniles varied from 86.33% to 93.66%,and there was no significant difference between experimental groups. The tested fish under higher light intensities (240 and 1000 lx) spent much more energy in respiration and excretion while depositing less energy for growth than those fish under lower light intensities. It is concluded that light intensity significantly affected growth and optimal light intensity for B. lenok juveniles was about 10–70 lx.     

温度、盐度和光照强度对鼠尾藻氮、磷吸收的影响

在实验室条件下,研究了不同的温度和盐度组合,温度和光照强度组合对鼠尾藻(Sargassum thunbergii)氮、磷吸收速率的影响.结果表明,上述3个环境因子对鼠尾藻氮、磷吸收速率均有显著影响.其中,温度和盐度对鼠尾藻氮、磷吸收速率有极显著影响(P<0.01),二者交互作用也极显著(P<0.01).在盐度20、温度25℃条件下和盐度30、温度30℃条件下,鼠尾藻对氮有较高吸收速率,分别为11.26μmol/[g(dw)·h]和11.01 μmol/[g(dw)·h];在盐度40、温度15～30℃范围内对磷的吸收速率较大,达到1.5μmol/[g(dw)·h]以上.温度和光照对鼠尾藻氮、磷吸收速率均有极显著影响(P<0.01),二者交互作用极显著(P<0.01).在温度15℃和光照强度140～180μE/(m2·s)以及温度20～25℃和光照强度60～100 μE/(m2·s)条件下,鼠尾藻对氮有较高吸收速率,均在9.60 μmol/[g(dw)·h]以上;在温度25℃和光照强度60μE(m2·s)条件下,鼠尾藻对磷的吸收速率达到最大,为1.30 μmol/[g(dw)·h].本研究结果表明,鼠尾藻总体上对水体中的氮、磷均具有较高的吸收速率,且能较好地同时吸收NH4+-N和NO3--N,显示了它对海水环境中营养盐具有较强的吸收能力.     

Effects of light intensity on larval development and juvenile growth of sea cucumber Apostichopus japonicus

The growth rate, survival rate, development and setting rate of larval sea cucumber Apostichopus japonicus were measured under four light intensities (0, 50, 500 and 2,000 lx), and the growth rate and metabolism of the juvenile sea cucumbers were investigated under four light intensity treatments (0, 100, 1,000 and 2,500 lx). The light requirements (i.e. intensity) of the sea cucumber changed as they grew. Better growth performance, development and survival rate were observed in embryos and larvae under 500 lx treatment. However, reduced light intensity (50 lx) increased the settlement rate of the larvae. The highest specific growth rate occurred in juvenile sea cucumbers under 1,000 lx. The sea cucumbers in this group also had the lowest oxygen consumption rate and ammonia excretion rate, but the highest O:N ratio, indicating that the optimal light intensity for the juvenile sea cucumber culture was 1,000 lx. Therefore, appropriate light intensities were suggested to provide larval and juvenile sea cucumbers with better growth and development conditions.     

光照强度、温度和盐度对鹿角沙菜生长及生化组分的影响

以鹿角沙菜（Hypneacervicornis）为材料,分别研究了其在不同光照强度（2000lx、4000lx、7500lx、10000lx和15000lx）、不同温度（15℃、20℃、25℃、30℃和35℃）、不同盐度（5、10、15、20、25、30和35）下生长及生化组分的变化。结果显示,适合鹿角沙菜生长的光照强度为2000—4000lx,温度为20～30℃,盐度为20—35;最适合生长的光照强度为4000lx,温度为25℃,盐度为30,在此条件下藻体具有最高的相对生长速率（RGR）,SOD活性最低。在光照强度4000～5000lx范围内随着光照强度的升高,可溶性蛋白（SP）、叶绿素a（Chl—a）和类胡萝卜素（Car）的质量分数降低,而藻红蛋白（PE）和藻蓝蛋白（Pc）的质量分数上升;在温度25～35℃、盐度30～35范围内随着温度、盐度的升高,可溶性蛋白、叶绿素a、类胡萝卜素、藻红蛋白和藻蓝蛋白的质量分数降低,说明适宜的温度和盐度有利于其生化组分积累。     

光照强度、温度和盐度条件对鹿角沙菜生长及生化组分的影响

以鹿角沙菜（Hypnea cervicornis）为材料,分别研究了其在不同光照强度（2 000 lx和4 000 lx和7 500 lx、10 000 lx和15 000 lx）、不同温度（15 ℃、20 ℃、25 ℃、30 ℃和35℃）、不同盐度（5、10、15、20、25、30和35）下生长及生化组分的变化。结果显示,适合鹿角沙菜生长的光照强度为2 000~4 000 lx,温度为20~30 ℃,盐度为20~35;最适合生长的光照强度为4 000 lx,温度为25 ℃,盐度为30,在此条件下藻体具有最高的相对生长速率（RGR）,SOD活性最低。在光照强度4 000~5 000 lx范围内随着光照强度的升高,可溶性蛋白（SP）、叶绿素a（Chl-a）和类胡萝卜素（Car）的质量分数降低,而藻红蛋白（PE）和藻蓝蛋白（PC）的质量分数上升;在温度25~35 ℃、盐度30~35范围内随着温度、盐度的升高,可溶性蛋白、叶绿素a、类胡萝卜素、藻红蛋白和藻蓝蛋白的质量分数降低,说明适宜的温度和盐度有利于其生化组分积累。

     

The Effects of light intensity on growth and survival of cuttlefish (sepia officinalis) hatchlings and Juveniles

The effects of three light intensities (100, 350 and 1200 lux) on cuttlefish hatchling rearing performance was studied in black tanks. A total of 270 cuttlefish with a mean wet weight (MWW) of 0.089 ± 0.012 g were used in the experiment, which was undertaken during the first 50 days after hatching (hatchling stage plus the transition to the juvenile stage). According to results of the present study, light intensity is an important factor for growth and survival consistency in cuttlefish rearing. All three light intensity groups displayed exponential growth. The effect of days, light intensity and their interaction only displayed differences (P < 0.05) between light groups in terms of mean wet weight. The 100 lux light intensity promoted the best absolute values of total biomass and total mortality. We believe that the higher mortality observed in 1200 lux reared cuttlefish during the first 10 days after hatching (DAH) was due to light intensity and individual adaptation to light conditions. Therefore, the 100 lux light intensity, obtained with daylight spectrum bulbs, is recommended for cuttlefish rearing during the first 50 DAH. This light setup promotes higher growth and survival rates and lower energetic costs, which are key aspects to consider in a cuttlefish hatchery.     

Effects of light spectrum and intensity on growth,survival and physiology of leech (Whitmania pigra) larvae under the rearing conditions

Used as a traditional Chinese medicine, the high mortality rate and slow growth of Whitmania pigra larvae are the most serious bottlenecks for the scale development of artificial breeding. Firstly, five light colour treatments (white, blue, green, red and yellow) were tested to determine effects of light spectrum on the growth of larval W. pigra at the same intensity of 70.00 μmol m^?2 s^?1. The experiment lasted for 45 days. Under our experimental conditions, the weight gain (WG) and the specific growth rate (SGR) under blue light condition were significantly higher compared with the other treatments (P ≤ 0.05). It is reasonable to conclude that blue light can promote the leech growth. In addition, reared at five blue light intensity treatments (20.00 ± 3.84, 40.78 ± 4.18, 53.67 ± 5.98, 70.00 ± 7.26 and 87.33 ± 5.77 μmol m^?2 s^?1), the WG and SGR increased with increasing intensity. Meanwhile, they were significantly higher in the 70.00 and 87.33 μmol m^?2 s^?1 treatments (P ≤ 0.05). In the higher intensity light treatments, the digestive enzymes were higher and antioxidant enzymes were lower. These results suggest that the optimal light spectrum for the culture of W. pigra during the early life stage was blue and the optimal light intensity was higher light intensity (70.00–87.33 μmol m^?2 s^?1).     

光照强度对黄颡鱼生长和生理性能的影响

使用光强控制法,探究了光照强度1-8W/m2范围内黄颡鱼（Pelteobagrus fulvidraco）生长、生理性能影响。结果表明,光强3-6W/m2黄颡鱼的增重率（8.33-11.78%）、特定增长率（0.53-0.74%）最高,饵料系数最低（6.42-9.17）,黄颡鱼体内的胃蛋白酶、脂肪酶活性和丙二醛含量升高（P＜0.01）,而超氧化物歧化酶、过氧化氢酶、谷胱甘肽过氧化物酶、碱性磷酸酶和酸性磷酸酶活性降低（P＜0.01）,抗氧化、免疫性能受到抑制,因光照影响黄颡鱼的生长和消化性能,不同光强条件下养殖水体中的氨氮、溶氧等水质指标出现差异。本研究为黄颡鱼高效养殖提供了理论依据。     

静止和充气培养条件下光强对龙须菜光合生理效应的影响

为研究充气和光强变化对大型海藻生长的影响,选择了常见的经济海藻龙须菜（Gracilaria lemaneiformis）为实验材料,将静止和充气培养的藻体暴露在 50 μmol/(m2 s)（低光）、100 μmol/(m2 s)（中光）和200 μmol/(m2 s)（高光）下,测定其生长、光合作用以及光合色素含量。结果表明,中光处理的龙须菜相对生长速率最大,光强过低或者过高均会抑制其生长。充气促进低光、中光和高光处理藻体的生长,相对生长速率分别提高26.85%、31.82%和40.56%。充气可使低光处理的藻体光合作用速率和光合效率分别提高8.14%和4.26%,可使高光处理的藻体呼吸作用速率降低20.70%、有效光化学效率（Yield）升高44.16%。这些结果说明,低光对生长的影响主要是由于藻体光合作用受到光限制,而高光对生长的影响是因为藻体呼吸作用增强。充气可以缓解因为光线不足或者高光损伤而对龙须菜生长造成的负面影响。     

Effects of dietary substitution of fishmeal with the combined dry microalgae,Nannochloropsis oceanica (NO) biomass residue and casein on growth and body composition of juvenile abalone (Haliotis discus)

The effects of dietary substitution of fishmeal with the combined dry Nannochloropsis oceanica (NO) biomass residue and casein on growth performance and carcass composition of juvenile abalone was determined. One thousand two hundred and sixty juvenile abalone were randomly distributed into the 18 L plastic rectangular containers. Five experimental diets in triplicate were prepared. The 28% fishmeal was included into the control (Con) diet. The 25%, 50%, 75% and 100% fishmeal were substituted with the combination of graded levels of dry NO biomass residue and casein, referred to as the NO25, NO50, NO75 and NO100 diets respectively. Finally, the salted sea tangle (ST), Laminaria japonica was prepared to compare the effect of the experimental diets on performance of abalone. The essential amino acids, such as isoleucine, leucine, phenylalanine, threonine and valine tended to increase with dietary substitution of fishmeal with NO biomass residue in the experimental diets. Arginine tended to decrease with dietary substitution of fishmeal with NO biomass residue. Survival of abalone fed the experimental diets was higher than that of abalone fed the ST diet for 16 weeks. Weight gain and specific growth rate (SGR) of abalone fed the NO100 diet were higher than those of abalone fed the all other diets. Weight gain and SGR of abalone linearly increased with dietary substation of fishmeal with NO. Shell length of abalone tended to increase with dietary substitution of fishmeal with the combined dry NO biomass residue and casein. The chemical composition of the soft body of abalone was different among treatments except for moisture content. In conclusion, fishmeal in the diets for abalone could be completely replaced with the combined dry NO biomass residue and casein when the 28% fishmeal was included.