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1.
Cu2+对大型蚤生长和繁殖的影响 总被引：1，自引：0，他引：1
研究了不同浓度Cu2+对大型溞生长和繁殖的毒性影响.试验观察了大型溞的繁殖指标(产第1胎时间、每只溞所产总幼溞数、每只溞所产总胎数和内禀增长率),同时还观察了存活和生长(体长)2个指标.试验结果显示,随着Cu2+浓度的增加,内禀增长率显著F降,但是生长和存活仅在9.6μg/L Cu2+浓度下显著下降.产第1胎时间随Cu2+浓度增加而延长;表明Cu2+低浓度下对水生生物的长期慢性影响不容忽视.大型溞繁殖指标可作为水环境Cu2+污染预警生物标志. 相似文献
2.
应用生命表统计学方法,在0.5×10~6、1.0×10~6和2.0×10~6 cells/mL的斜生栅藻(Scenedesmus obliquus)密度下研究了Zn~(2+)浓度(20.0、50.0、80.0、110.0和140.0μg/L)对多刺裸腹溞(Moina macrocopa)生命表统计学参数的影响。结果表明,Zn~(2+)浓度对多刺裸腹溞的种群内禀增长率有显著影响(P0.05),藻密度对多刺裸腹溞的世代时间、净生殖率和种群内禀增长率均有显著影响(P0.05),藻密度和Zn~(2+)浓度间的交相互作作用对多刺裸腹溞各主要生命表统计学参数都没有显著的影响(P0.05)。三食物密度间,多刺裸腹溞的世代时间在1.0×10~6 cells/mL食物密度下显著短于0.5×10~6和2.0×10~6 cells/mL食物密度下;净生殖率和种群内禀增长率均在1.0×10~6 cells/mL食物密度下最高,2.0×106 cells/mL食物密度下最低。50.0和80.0μg/L的Zn~(2+)使多刺裸腹溞的种群内禀增长率显著高于对照组和其它各Zn~(2+)浓度组。Zn~(2+)浓度与多刺裸腹溞的生命表统计学参数中的生命期望和平均寿命在0.5×10~6 cells/mL食物密度下存在着显著的剂量-效应关系,可分别描述为:e0=-0.004x~2+0.063x+348.604(R~2=0.434, P0.05)和t=-0.025x~2-0.507x+84.468(R~2=0.434, P0.05)。 相似文献
3.
为了解无鱼条件下贫营养水体中大型枝角类盔形溞(Daphnia galeata)的种群动态及其对浮游动物群落结构的影响,于2010年3月5日至4月18日在流溪河水库进行围隔试验,设置1个对照组和3个处理组,每个处理有3个重复。对照组(C)为用孔径约2 mm的网过滤后的水库水抽入围隔,试验组抽入过滤后的水库水后添加高、中、低密度(H,M,L)的盔形溞,对照组和试验组添加的盔形溞密度梯度分别为0、0.3、0.6、1.0个/L。无鱼条件下盔形溞种群快速形成高峰,但随后由于食物限制又快速下降。盔形溞高密度种群的建立对轮虫种群产生了显著影响,试验开始后轮虫受到盔形溞抑制而密度下降。在试验后期,食物数量下降,盔形溞密度下降并维持在较低的密度,而大型桡足类中的舌状叶镖水蚤(Pyllodiaptomus tunguidus)密度增加,显示了竞争优势。由于大型围隔试验对浮游动物操作的可重复性较差,个别围隔中出现了透明薄皮溞(Leptodora kindti),也对盔形溞种群及浮游动物群落结构产生了影响。 相似文献
4.
为了探究培养隆线溞(Daphnia carinata)的适宜饵料,选用玉米粉、酵母、小球藻粉(Chlorella sp.)、裂壶藻粉(Schizochytrium sp.)、绿球藻(Chlorococcum sp.)和微绿球藻(Nannochloropsis oculata)6种饵料分别喂养隆线溞,并测定隆线溞的生长繁殖参数、饵料营养组成及养殖水体水质和细菌含量等参数。结果显示,投喂绿球藻组隆线溞在培养各阶段均具有最高的成活率;投喂小球藻粉、绿球藻和微绿球藻组隆线溞首次产子代时间(4.0 d)显著快于其他各组;投喂绿球藻组隆线溞具有最大的繁殖量(375.2 ind);投喂玉米粉组子代存活率显著低于其他其他组。投喂绿球藻组隆线溞具有最大的净繁殖率R0 (293.3),且显著高于其他组;投喂小球藻粉组隆线溞具有最短的平均世代时间T (5.0 d),且显著低于其他组;投喂小球藻粉、绿球藻和微绿球藻组隆线溞的内禀增长率rm和周限增长率λ无显著差异(P>0.05), 3组均显著高于其他组(P<0.05)。对饵料营养组成与隆线溞生长繁殖参数进行相关性热图分析显示,饵料蛋白含量与隆线溞首... 相似文献
5.
采用试验生态学方法,在恒温(20±1)℃条件下,研究盐度变化对透明溞存活、生长和繁殖的影响。试验结果显示,透明溞的24 h和48 h半致死盐度分别为4.16和2.67,安全盐度为0.36。透明溞的产前发育期和有效积温随盐度上升而增加;体长增长率随盐度的升高先升后降,存活时间和内禀增长率随盐度的升高而下降。盐度对透明溞生存、生长及繁殖的影响显著(P<0.05),0.5盐度组的透明溞壳刺长显著大于对照组。研究结果表明,透明溞为嫌盐种,对盐度耐受性低。透明溞可作为水产经济动物开口饵料、水体盐碱变化的指示生物,对水环境监测具有重要意义。 相似文献
6.
在静置换水30±0.5℃条件下,对微型裸腹溞、隆线溞生物学进行了研究,结果表明:微型裸腹溞有2个幼龄和9个成龄期,寿命为10.6天,累计产卵48个,产卵率(b)为1.0542,种群的内禀增长能力(r_m)、净增率(R_o)、世代平均周期(T)和周限增长率(λ)分别为0.7863、26.33、4.1596日和2.1952/日。其日龄(t)与体长(l_t)之间呈双曲线回归关系:l_t=(t/0.9317t+1.2265)(r=0.9724,在α=0.001水平上显著)。隆线溞3个幼龄和14个成龄,寿命为18.7天,累计产卵366个,产卵率(b)为1.4127,种群的内禀增长能力(r_m)、净增率(R_o)、世代平均周期(T)和周限增长率(λ)分别为0.7247、125.3994、6.6666日和2.0642/日,体长(l_t)增长模型为:l_t=(t/0.2204t+1.5730)(r=0.9976,r 在α=0.001水平上显著)。 相似文献
7.
为研究用冷冻糠虾替代鲜活糠虾作灰海马亲鱼饵料的可行性,通过饲喂试验,比较了鲜活糠虾(A组)和冷冻糠虾(B组)对灰海马产仔数量、胚胎发育时间、初孵仔鱼的体长、体质量及其在15日龄时的生长和成活率的影响.结果表明,水温28℃,盐度33时,两个处理组在产仔数量、胚胎发育时间、初孵仔鱼的湿重、体长、肥满度、15日龄时的湿重增量、湿重的绝对增长率均无显著差异,而A组15日龄仔鱼体长的增量为1.464 cm,显著高于B组的0.699 cm(P=0.039),A组的体长绝对增长率为0.100,极显著高于B组的0.050(P =0.0039).A组仔鱼的成活率为97.65％,极显著高于B组的66.72％(P =0.007).相对于冷冻糠虾,鲜活糠虾能够更好地满足灰海马亲鱼的营养需求,提高子代的生长性能和成活率. 相似文献
8.
随着水体富营养化和全球变暖,微囊藻水华在低盐度封闭海域也时常发生。为探讨低盐度封闭海域中的铜绿微囊藻的毒性对盐水枝角类动物生殖、抗氧化酶的重要影响,在室内条件下培养耐盐为8的有毒铜绿微囊藻,分别开展不同藻密度的有毒铜绿微囊藻[4个有毒铜绿微囊藻处理组、1个对照组(小球藻)、1个禁食组]、不同组合的混合饵料(设置4个处理组和1个对照组,藻密度为1×105个/mL)对蒙古裸腹溞生长繁殖的影响,以及不同食物条件对蒙古裸腹溞体内超氧化物歧化酶和过氧化氢酶活性的影响。结果显示：在不同的藻密度条件下,随着有毒铜绿微囊藻藻密度增大,蒙古裸腹溞寿命显著减短,并且在有毒铜绿微囊藻处理组中均无繁殖现象;在混合饵料(小球藻+有毒铜绿微囊藻)条件下,有毒铜绿微囊藻占比越大,蒙古裸腹溞的净生殖率越低,世代时间越短;在96 h的酶活性测试中,与小球藻组相比,暴露在有毒铜绿微囊藻条件下的蒙古裸腹溞的超氧化物歧化酶和过氧化氢酶活性随时间显著下降。研究表明,有毒铜绿微囊藻显著抑制蒙古裸腹溞的种群生长。在2种食物条件下,添加小球藻可以缓解铜绿微囊藻对蒙古裸腹溞的毒害作用,同时铜绿微囊藻的毒性也显著影... 相似文献
9.
氟他胺对萼花臂尾轮虫的毒性影响 总被引：2，自引：0，他引：2
采用两天种群增长和生命表,研究了不同浓度氟他胺对萼花臂尾轮虫(Brachionus calyciflorus)的毒性影响。结果显示:轮虫种群增长率与氟他胺浓度对数负相关。氟他胺对萼花臂尾轮虫种群增长率的半效应浓度(EC50)、最低可见效应浓度(LOEC)和无可见效应浓度(NOEC)分别为4.31、3.17和1.59 mg/L。氟他胺对萼花臂尾轮虫的内禀增长率和世代时间有显著的影响(P<0.05);内禀增长率随氟他胺浓度升高而下降,其中1.59 mg/L和3.17 mg/L氟他胺浓度组内禀增长率分别比对照组降低了8.98%和17.95%(P<0.05),其无效应浓度为0.8 mg/L;而3.17 mg/L浓度组的世代时间显著延长(P<0.05)。实验结果表明内禀增长率是检测氟他胺对萼花臂尾轮虫毒性最敏感的指标。 相似文献
10.
水体营养水平及附着藻类对苦草生长的影响 总被引：3，自引：0，他引：3
为研究不同水体营养水平及附着藻类对沉水植物生长的影响,选择苦草(Vallisneria natans)作为研究对象,在4种水体营养水平下进行42 d的室内试验。结果表明:试验结束时,中营养及富营养处理组苦草的相对生长率、超氧化物歧化酶(SOD)活性、丙二醛(MDA)含量和附着藻类生物量与贫营养及重富营养处理组具有显著性差异(P<0.05);贫营养处理组苦草的可溶性糖含量显著高于其它处理组(P<0.05);苦草氮磷含量及可溶性蛋白含量与水体营养水平呈明显正相关,且贫营养及中营养处理组与富营养及重富营养处理组之间差异显著(P<0.05);各处理组水体叶绿素a含量差异不明显。表明在中营养(TN=0.8 mg/L,TP=0.08 mg/L)条件下,苦草的生长情况最佳。 相似文献
11.
以南亚热带地区2010年3座不同养殖密度的和龙水库、百花林水库、芙蓉嶂水库为对象,研究了浮游动物群落的结构特征,分析和探讨滤食性鱼类捕食对浮游动物群落结构的影响.3座水库浮游动物生物量均较低,不超过1.0 mg/L.高养殖密度、富营养水平的和龙水库浮游动物生物量显著低于其它2座水库,中等养殖密度、富营养水平的百花林水库则高于低养殖密度、贫-中营养水平的芙蓉嶂水库.和龙水库浮游动物全年以轮虫为主要优势类群,优势种为前节晶囊轮虫(Asplanchna priodonta);芙蓉嶂水库和百花林水库3月和12月浮游动物以枝角类为优势类群,优势种为长额象鼻溞(Bosmina longirostris)、颈沟基合溞(Bosminopsis deitersi)、模糊秀体潘(Di-aphanosoma dubium),8月为桡足类,优势种为舌状叶镖水蚤(Phyllodiaptomus tunguidus).3座水库年均浮游动物与浮游植物生物量比值均小于0.1,与年渔获量呈显著负相关关系.高强度的滤食性鱼类捕食使得下行效应比上行效应更强烈,浮游动物表现出低生物量和小个体种类占优势的特征. 相似文献
12.
《Journal Of Applied Aquaculture》2013,25(1):45-55
Four 20m3 cages stocked with 120 bighead carp x silver carp hybrids per cage were placed in each of four ponds varying in trophic status from mesotrophic to hypereutophic. Fish were cultured, without feeding, from 13 March to 1 Octorber 1987. Fish in the mesotrophic pond survived but lost weight (-0.37 g/fish/d). The mesotrophic pond produced insufficient food to sustain fish growth. Maximum fish growth rate occured in the two eutotrophic ponds (6.61vand 7/04 g/fish/d). Fish growth in the hypereutrophic pond was about one-half (3.64 g/fish/d) that in the two eutrophic ponds. Guy analysis of fish in the hypereutrophic pond revealed consumption of larger quantities (P < 0.05) of colonial blue-green algae that were apparently poorly digested and less (P < 0.05) zooplankton (primarily cladocerans) than was found in fish from the eutrophic ponds. 相似文献
13.
2010年5月（春季）、7月（夏季）、10月（秋季）对乌苏里江下游浮游动物的群落结构、季节变动、多样性及在河流健康评价中的地位进行了调查与研究,旨为乌苏里江渔业资源增殖放流提供背景资料。结果表明,乌苏里江下游（海青-乌苏镇江段）以原生动物（数量占87.7%）和轮虫（生物量占68.4%）为主,趋向小型化,且浮游动物的多样性较为丰富,为乌苏里江下游大麻哈鱼等许多名优水产动物的繁殖、育肥提供丰富的饵料基础。浮游动物个体较小、数量多、代谢活动强烈、繁殖迅速、易于散布,能对水体提供快速的早期反映;是食物网的重要基础环节,在水域生态系统的物质循环与能量流动中占有重要地位,是河流水生生物资源的重要组成部分,是河流健康评价的重要指标之一。 相似文献
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15.
Effects of stocking density and natural food availability on the extensive cage culture of pejerrey (Odontesthes bonariensis) in a shallow Pampean lake in Argentina 
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下载免费PDF全文 Javier Ricardo Garcia de Souza Patricio José Solimano Tomás Maiztegui Claudio Rafael Mariano Baigún Darío César Colautti 《Aquaculture Research》2015,46(6):1332-1344
An experiment was conducted for 80 days at La Salada de Monasterio Lake (Buenos Aires, Argentina) to assess the effect of stocking density and natural food availability on the growth and production of zooplanktivorous juveniles of pejerrey (Odontesthes bonariensis) in extensive cage culture. Ten cages were installed and stocked with 33‐day‐old fish, at three density treatments: 25, 50 and 75 ind. m?3. Zooplankton was analysed in terms of abundance, biomass and diversity considering three size classes. Caged pejerrey diet was assessed regularly. The pejerrey gut contents composition was clearly different from cage zooplankton, showing a trend to contain bigger components. Reared fish exhibited a tendency to diversification of the diet and to change the mean prey size depending on fish length and stocking density. Regression models showed a positive and direct effect of the bigger zooplankton biomass on fish growth rates, which were also inversely affected by the availability of smaller zooplankton. The results demonstrate that stocking density and available zooplankton, in both quantity and quality, are key factors in regulating extensive cage culture of pejerrey. Handling stocking densities in a dynamic way it is possible to maximize fish growth, biomass harvest or fish number according to the goals of production. 相似文献
16.
Konrad Dabrowski 《Aquaculture (Amsterdam, Netherlands)》1984,40(1):27-40
In a series of trials, larvae of common carp (Cyprinus carpio L.), silver carp (Hypophthalmichthys molitrix Rich.), grass carp (Ctenopharyngodon idella Val.) and bighead carp (Aristichthys nobilis Rich.) were transferred directly from a diet of zooplankton to a dry, compound feed. The dry diet was based on a previously described diet of yeast and freeze-dried animal tissues. Common carp larvae showed the best growth on live zooplankton (46.3 mg individual weight after 14 days) compared to fish fed solely on dry feed (13.8 mg). Transfer of common carp larvae to dry diet when they reached 4.27 mg significantly improved growth, but no dependence was observed on two diets tested. Grass carp larvae grew equally well on live food and on the best compound diet (8.7 mg after 15 days), but fish transferred to dry diet at 4.3 mg showed significantly improved growth. The growth rate, however, depended on the diet (12.9–23.5 mg). Silver carp grew better when fed solely on dry diet (23.5 mg), compared to live zooplankton (15.8 mg after 15 days), but this was due to an insufficient supply of suitable live food. Transfer of fish at 6.8 mg to dry diet improved the growth only slightly, and dependence on the kind of dry diet was observed. Bighead carp larvae showed better growth on live zooplankton (42.2 mg after 15 days) than on the best compound diet (18.6 mg). Fish transferred at 5.6 mg to dry diets showed good growth, but high mortality was observed. It was concluded that common carp larvae are the most “difficult” to raise solely on dry diet, whereas silver carp larvae are the “easiest”. The present study has shown that the transfer of four cyprinids to dry diet improved their growth rate and that the transfer is possible at the individual wet weight of 5–6 mg. 相似文献
17.
In the field of live food science, newly inbred strains resulting from cross-mating are of interest, especially if these strains have valuable characteristics, such as high fecundity or suitable size for the mouth of larvae. We conducted cross-mating trials using Japanese and German strains of Brachionus plicatilis and reproductive parameters were characterized and compared among their progenies. Two hybrid strains A and B were obtained from the cross-mating between a Japanese female and German male, and between a German female and Japanese male, respectively. Percent mictic female production and fertilization in both hybrid strains were lower (0%), compared with the parental strains (16.7-78.4%). Strain A did not reproduce sexually, but was capable of asexual reproduction. Higher population growth was observed in the hybrid strains within crosses relative to parents. The population growth rates of parental strains were 0.31, while those of hybrid strains ranged from 0.35 to 0.37. Lorica length of hybrid strains was intermediate between the two parental strains. Using the cross-mating technique, it may be possible to produce new rotifer strains with phenotypes useful to aquaculturists. 相似文献
18.
The effect of dietary protein source on growth and carcass composition in juvenile Australian freshwater crayfish 总被引：1，自引：0，他引：1
A feed trial was conducted for 12 weeks on juvenile Australian freshwater crayfish (Cherax destructor) (mean weight (SE) 0.82 (0.02)g) maintained on five isoenergetic diets with a protein content of 30%. Diets differed in the primary source of protein used, with meat, snail, soybean, yabby, and zooplankton meals comprising the major protein ingredient, varying from 56–60% of total protein. Mean percentage weight gain per day ranged from 7.57% (yabby meal diet), to 9.42% (snail meal diet). No significant difference occurred in mean weight, percentage weight gain, specific growth rate (%), or survival among diets. A maximum size of 16.44g was attained on the yabby meal diet. Largest mean weight was 8.27g on the snail-based diet. Food conversion ratios were all good, with a minimum value of 0.95 recorded for the snail-based diet. Initial food consumption per day was approximately 5% of mean animal weight, decreasing to around 2.4%, and is collectively described by a power curve. Protein retention ranged from 29.57% in the zooplankton meal diet to 41.15% in the snail-based diet. Carcass composition was influenced by feed type, with the most marked difference occurring in carapace colour. Animals fed the zooplankton-based pellets developed the strongest pigmentation. Recommendations are made for including certain protein-based ingredients in manufactured yabby diets. 相似文献
19.
Fish raised in ponds and fed formulated feed also have access to naturally occurring food items. The contribution of these food items to growth of Bidyanus bidyanus was investigated by assigning fish to four treatments: in diet 1, caged fish were fed a high protein feed (52% CP); in diet 2, caged fish were fed a medium protein feed (30% CP); in diet 3, caged fish received no feed; and in diet 4, uncaged fish received no feed. Survival between caged treatments was similar (88%–96%), and fish performed best when fed a high-protein feed. Modelling of C and N stable isotope ratios showed formulated pellets provided 12% to 84% of the growth of fish fed diet 1 or 2, while invertebrates provided between 4% and 74%. The majority of growth of fish in diet 3 was from zooplankton (54%–76%) and invertebrates for fish in diet 4 (6%–94%). Implications for low intensity production of B. bidyanus are discussed. 相似文献