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1.
Jorge Hernández Iker Uriarte María Teresa Viana Renato Westermeier & Ana Farías 《Aquaculture Research》2009,40(15):1694-1702
A feeding experiment was carried out to evaluate two natural diets versus a formulated feed on the performance of weaning red abalone Haliotis rufescens . Four treatment diets were then investigated: a formulated diet; plantlets from culture Macrocystis pyrifera, Porphyra columbina from natural beds; and a mixed diet consisting of a blend of fresh P. columbina together with the formulated diet. This study was performed in a shallow aquaculture system with a horizontal water flow. After 90 days, significant differences were observed between treatments. The highest growth was obtained with Porphyra (3.3 mm month−1 ), followed by the mixed diet (2.6 mm month−1 ), then Macrocystis (2.1 mm month−1 ) and lastly the formulated diet (1.4 mm month−1 ). Moreover, after the diets were tested for stability and remnant nutrients after a 12-h water immersion, a positive trend appeared to be related to the protein/energy (P:E). It is concluded that fronds of P. columbina resulted in the best diet for weaning H. rufescens under horizontal water flow systems, even if apparently the water stability of the formulated diet had a negative impact on abalone performance, particularly due to a poor nutrient retention capacity. Therefore, formulated diets should be improved before being recommended for weaning red abalone. 相似文献
2.
南京幕府山矿区废弃地自然恢复植被的构树种群及其伴生树种生态位研究 总被引：2，自引：0，他引：2
以南京幕府山矿区废弃地自然恢复的植被优势种群为对象，对构树及其伴生树种的生态位宽度和生态位重叠进行了研究。结果表明：研究的9个树种的生态位总体比较接近，都有比较宽的生态位，从群落形成的时间分析，这些树种是在矿区废弃地上的先锋树种，对废弃地有较强的适应能力。因此，在人工恢复这一地区矿区废弃地植被时，可以选用这些树种。构树的生态位较宽。而其与其他树种的生态位重叠却不是很大，构树在一定时期内，还是矿区废弃地上植物群落的最主要的优势树种，是矿区废弃地最适应的树种之一，可以作为本地区矿区废弃地植被恢复的首选树种。 相似文献
3.
Renato Westermeier David Patiño Maria Ines Piel Ingo Maier & Dieter G Mueller 《Aquaculture Research》2006,37(2):164-171
Substantial amounts of Macrocystis and Lessonia are traditionally harvested and exported from Chile as raw material for alginate. Because of intense mariculture of abalone (Haliotis ssp.), herbivorous molluscs that feed on brown kelps, pressure on local populations of Macrocystis and Lessonia has increased to critical levels within the past 5 years, strongly supporting efforts to produce algae maricultured biomass. Here, we present our results on the development of new techniques for large‐scale kelp mariculture in Chile. We have abandoned the traditional technique of direct spore seeding onto inoculation lines. Instead, we used gametophyte cultures that were manipulated to enter gametogenesis and to produce synchronous batches of 104–105 embryos. Juvenile sporophytes were cultured under permanent aeration and agitation, floating unattached in contamination‐free glass bottles up to 10 L, plexiglass cylinders and 800 L greenhouse tanks. When holdfast initials were formed at a size of 8 cm, the sporophytes were spliced into Nylon rope fragments and transferred to the sea. Twelve months after initiation of gametogenesis in the laboratory, Macrocystis pyrifera attained 14 m length and 80 kg fresh weight m?1 line in the sea. For Lessonia trabeculata 6 months after gametogenesis initiation, 0.25 kg fresh weight m?1 was attained in the sea. 相似文献
4.
Increased gonad growth of the purple sea urchin (Strongylocentrotus purpuratus) fed the giant kelp (Macrocystis pyrifera) and the sea lettuce (Ulva lactuca) enriched with nutrients 
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下载免费PDF全文 Adult (Strongylocentrotus purpuratus) purple sea urchins were fed giant kelp (Macrocystis pyrifera) and sea lettuce (Ulva lactuca) macroalgae that were unenriched and enriched with nutrients. Urchins were fed over 10 weeks (5% body weight per day) under laboratory conditions to determine the effect of macroalgae species and treatment (enriched and unenriched) on growth, gonad index and gonad quality. Significant differences were observed when urchins were fed enriched Macrocystis pyrifera (MPE). Gonad weight increased from 0.7 ± 0.1 g (mean ± SD) to 5.9 ± 1 g, and gonad index increase from 3.5 ± 1.5% to 14.9 ± 2.3% over 10 weeks. Significant differences were also noted in gonad quality, and gonad colour and firmness were better in urchins that were fed unenriched M. pyrifera (MPUE) and MPE – whereas texture did not differ between M. pyrifera treatments and unenriched U. lactuca (ULUE). With regard to taste, gonads were sweeter in MPE‐fed individuals. Enriched U. lactuca (ULE) failed to grow gonads significantly; as a result, their quality was unacceptable for the market. These results suggest that S. purpuratus experience increased gonad production and quality in short periods when fed nutrient‐enriched M. pyrifera. 相似文献
5.
Production and economic assessment of giant kelp Macrocystis pyrifera cultivation for abalone feed in the south of Chile 下载免费PDF全文
下载免费PDF全文 Tomás Correa Alfonso Gutiérrez Roberto Flores Alejandro H Buschmann Patricio Cornejo Cristian Bucarey 《Aquaculture Research》2016,47(3):698-707
Kelp biomass availability for mass abalone cultivation remains a critical issue in Chile. The technical and economic feasibility of a commercial scale kelp farming activity has not been established. This study describes the production and economic results of a pilot scale unit installed in southern Chile. Our results show 25 kg m?1 of production over a 9‐month spring‐summer period, and 16.2 kg m?1 during the autumn‐winter period. These values indicate that a total biomass production of 41.3 kg (wet) ma?1 year?1 can be obtained by placing the culture lines at 4 m intervals. High quality animal food‐grade plants with a 9% protein content, over 5 m in length were harvested. Sensitivity analysis showed that by cultivating 30–50 ha with a market value of US$ 78 ton?1, a return on investment can be made after the first year. 相似文献
6.
Variation in morphology and PSII photosynthetic characteristics of Macrocystis pyrifera during development from gametophyte to juvenile sporophyte 下载免费PDF全文
下载免费PDF全文 Dong Xu Naihao Ye Shaona Cao Yitao Wang Dongsheng Wang Xiao Fan Xiaowen Zhang Meiling An Shanli Mou Yuze Mao 《Aquaculture Research》2015,46(7):1699-1706
Currently, there is increasing demand for brown kelp, especially Macrocystis spp., to support the development of the abalone industry and for use as raw material for the production of alginate. Thus, there is a need to supplement the naturally available kelp biomass with the development of mariculture techniques. In this study, we investigated whether it was possible to cultivate Macrocystis pyrifera sporophytes in the laboratory using gametophyte clones. We propagated gametophytes by periodic fragmentation and then mixed aseptically an equal number of male and female gametophytes to induce fertilization. Approximately 60 days after fertilization, numerous embryonic sporophytes emerged on the seed fibre. By using chlorophyll fluorescence technology, we investigated variation in the photosystem II (PSII) characteristics of M. pyrifera during development from the gametophyte to juvenile sporophyte stage. During this growth period, both the optimal (Fv/Fm) and effective (YII) PSII quantum yields increased significantly from the haploid gametophyte to diploid sporophyte stages. In addition, by comparing female gametophytes with male gametophytes, we found that female gametophytes were not only larger and more pigmented than the males, but also recorded higher values of Fv/Fm and YII. Our results supplemented information on the life cycle and PSII photosynthetic performance during the early development and confirmed the possibility of artificial seeding technology, both of which may contribute to mariculture of M. pyrifera in China in the near future. 相似文献
7.
Patricio Dantagnan Adrián Hernández Aliro Borquez Andrés Mansilla 《Aquaculture Research》2009,41(1):87-94
The use of macroalgae as an additional component in animal feeding has been studied. However, information on how it could influence muscle composition of fish body is scarce. This study evaluates four diets with different macroalgae inclusion levels (0%, 1.5%, 3% and 6%) to test the effect on body fatty acid composition of rainbow trout. Tanks with a volume of 600 L were stocked with 60.6 ± 7.9 g fish at a density of 45 individuals tank?1 and fed for 124 days. At the end of the experiment there were not significant differences (P<0.05) in muscle proximate composition among fish fed the different treatments. However, it was determined that inclusion of 3% and 6% of macroalgae meal resulted in a significant increase (P<0.05) of polyunsaturated fatty acids (PUFAs) in muscle. In summary, macroalgae meal in rainbow trout diets do not enhance the quantity of protein and lipid contents at muscle level but an addition of 3–6% might contribute to increase the level of PUFAs, specially EPA, DHA and LIN. Thus, use of macroalgae meal might help to increase lipid quality content in the final product due the beneficial effects of PUFAs for human health. 相似文献
8.
发展新养殖对象及异地栽培需首先掌握物种的生态适应性。有关巨藻(Macrocystis pyrifera)在我国海区适应性的研究甚少,海区养殖效果不理想,我国巨藻养殖业发展欠佳。本研究采用MaxEnt构建了巨藻的物种分布模型,当特征组合为乘积型特征(product features)、二次型特征(quadratic features)和片段化特征(hinge features),正则化参数为0.8时,模型预测性能最佳;综合考虑环境因子的相关性及对模型的贡献率,筛选出6项环境因子用于模型构建,其中,光强与温度对巨藻自然分布的影响最大,在光强不低于2 μmol/(m2·s)、年均温度范围10.5~17.0℃条件下,巨藻的适生概率较高。采用所构模型结合ArcGIS预测巨藻在我国的适生区：主要分布于黄渤海,约占该海域面积的13.17%,其中,边缘适生区为5.46%,低适生区为2.85%,中适生区为1.20%,高适生区为3.66%,表明辽东湾、渤海湾是巨藻引种养殖和藻场建设的适宜海域。 相似文献
9.
谷胱甘肽S转移酶(glutathione S-transferase, GST)是一个较大的基因家族,在生物体生长发育和对环境变化响应中发挥重要的调控作用。本研究从巨藻(Macrocystis pyrifera)配子体中克隆了6个完整的GST基因(mpgst1、mpgst2、mpgst3、mpgst4、mpgst5和mpgst6)。随后将6个巨藻GST基因分别转化至细长聚球藻(Synechococcus elongatus PCC7942)中,提取细长聚球藻转化株基因组DNA作为模板进行PCR验证及测定转化株GST酶活进行基因功能验证,结果显示,6个mpgst基因都分别成功整合到细长聚球藻的基因组中,但只有含mpgst1、mpgst4和mpgst6基因的细长聚球藻转化株(MG1、MG4和MG6)具有耐镉性。在镉离子胁迫下,细长聚球藻转化株MG1、MG4和MG6的生长、光合色素含量和叶绿素荧光参数Fv/Fm值均显著高于野生株(P<0.05)。本研究结果为进一步研究巨藻GST基因的抗重金属胁迫功能奠定了基础。 相似文献
10.
巨藻潜筏式养殖技术的研究 总被引：1，自引：0，他引：1
根据巨藻生长特点及大规模养殖生产需要而进行了潜筏式平差和潜筏式垂养比较;不同养殖密度与产量的关系;不同分苗时间对产量的影响及不同流速下的内外海区对巨藻生长的影响等多项研究。 相似文献