Seaweeds from the genus Caulerpa offer promise for bioremediation in integrated tropical aquaculture in northern Australia, as they are common on shallow reefs adjacent to where aquaculture is developing and their propagation is readily manipulated through fragmentation. Fragments of five varieties of Caulerpa had high growth rates (between 3 and 7% day−1 ) and high nitrogen content (up to 3% dry weight/0.2% fresh weight for Caulerpa taxifolia) in tank-based culture. These attributes combined confirm the promise for Caulerpa in integrated aquaculture, especially as certain species (Caulerpa lentillifera and Caulerpa racemosa) are valuable products. However, this potential was not realised when Caulerpa spp. were cultured in an in situ aquaculture context. Only a limited proportion of fragments (13%, predominantly C. taxifolia) persisted during a 6 week in situ experiment in a flow-through settlement (treatment) pond from an 800 tonne year−1 fish production facility. Mean growth of persisting pond fragments (less than 0.3% day−1 ) wasmuch less than concurrent tank cultures (3– 7% day−1 ). The factor most strongly influencing pond culture was the negative (smothering) impact of blooming filamentous algae (Cladophora and Chaetomorpha spp.). Poor pond growth of Caulerpa was further substantiated in an additional test, determining that persistence and growth (or lack thereof) was independent of initial seeding size of fragments. These results suggest that Caulerpa culture will not be easily integrated into settlement ponds in tropical aquaculture. However, because some species of Caulerpa grew well in tank-based systems (C. racemosa grew at N7% day−1 ) and others are capable of luxury uptake (Caulerpa serrulata and C. taxifolia almost doubled internal nitrogen in nutrient-rich water), Caulerpa species have application in bioremediation of intensive tankbased aquaculture and perhaps treated pond aquaculture effluent
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With the world’s rapidly expanding population, it is necessary to provide sustainable and nutritious food. Aquaculture is the world’s fastest growing food production sector and carries with it some major tradeoffs and constraints. It is facing a major sustainability challenge as it is heavily dependent upon marine-derived feedstocks such as fishmeal. With the inevitable increase in the price of fishmeal, declining supply and rising demand, more emphasis has been given to alternative feed sources. The partial replacement of fishmeal with plant based protein sources in the aquaculture has been steadily increasing, however, many of these ingredients can be used as human food directly. Furthermore, the anti-nutritional factors in many plant ingredients can have negative effects in carnivorous fish such as salmonids. Large efforts have been made to develop the technology to produce alternative protein sources by using unicellular microorganisms such as microalgae, yeasts, fungi or bacteria. In this thesis, we have produced microbial protein from Norwegian bioresources such as brown seaweed and Norway spruce that could partially replace fishmeal in the Atlantic salmon diets. The work included characterization of the feedstocks, enzymatic saccharification of seaweed, fermentation for microbial protein production and fish feed trials. This study is based on five research papers: A detailed characterization of Saccharina latissima biomass is presented in the Paper I. The paper describes the biomass production and chemical composition of S. latissima cultivated at different depths and harvested at different time points. The enzymatic saccharification process of S. latissima by using a blend of cellulases and an alginate lyase are described in Paper II. It was shown that the inclusion of alginate lyases improved the saccharification yield of the seaweed, particularly at high solid loading. The carbohydrate content and the enzymatic saccharification of the brown seaweeds Macrocystis pyrifera from Chile and Saccharina latissima from Norway was compared in Paper III. For both seaweeds, recombinant alginate lyases and oligoalginate lyases in combination with cellulases gave higher sugar release than using cellulases only. However, for saccharification of pretreated seaweed only cellulases were needed to achieve high sugar release, indicating that the pretreatment partially hydrolysed the alginate. Moreover, it was shown that seaweed hydrolysate could be used as a growth medium for the yeast Candida utilis.
The cultivation of microbial yeast (C. utilis) from enzymatic hydrolysates of brown seaweed and spruce at different fermentation scales was studied in Paper IV. The yeast product quality in terms of amino acids composition, and mineral content were also studied. A feeding experiment with Atlantic salmon showed that the yeast biomass could partly replace a fishmeal diet, without affecting the growth, but with sub-optimal nutrient digestibility. The nutrient digestibility of C. utilis cultivated from three different carbon and nutrient sources: 1) a blend of woody hydrolysate and molasses, 2) spend sulphite liquor, and 3) a blend of brown seaweed and woody hydrolysate, and the impact of the different yeast biomasses on faecal mineral excretion was evaluated in Paper V. Inclusion of 30 % yeast cultivated on seaweed and spruce hydrolysates resulted in reduced digestibility of protein compared to both the fishmeal-diet and the two other yeast-based diets. In conclusion, this study demonstrated a proof-of-concept for utilization of brown seaweed and wood biomass for the production of microbial protein ingredients for the aquaculture sector.
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Since the establishment of abalone farming, there has been an increase in the demand for Macrocystis as a food source. Therefore, the pressure on natural stock has also augmented and the sustainability of the actual harvesting practices has been questioned. In this article, an attempt to farm Macrocystis pyrifera by zoospores in northern Chile is described; initially under laboratory conditions and subsequently by cultivation in the sea. The experiments were executed during 1 year and two different cultivation methodologies were used: a direct and an indirect method. A maximum frond length of 175 cm was reached and 22 kg m−1 of rope was produced after 120 to 150 days of cultivation in the sea. The algae grew under both methodologies, and no differences in algal length and biomass were detected between the two cultivation systems. However, the direct culture method can be recommended for productive and practical reasons.
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The current work aimed to develop a cultivation method for macroalgae that can be applicable and economically profitable in the Atlantic Ocean. An offshore long-line macroalgal cultivation rig was designed by Ocean Rainforest Sp/f, tested in the Faroe Islands from 2010, and found suitable for cultivation in exposed and deep- water locations (water depth > 50 m). The economic risk related to lost cultivation structures was hereafter considered to be low. Saccharina latissima and Alaria esculenta were cultivated in commercial scale (5 km of growth lines). A high cost of seeding material and cost of deployment was reduced by testing multiple partial harvesting. Four non-destructive harvests were carried out in a two-year growth period without re-seeding of lines. In total, 3.2 t dry weight (dw) biomass was harvested and sold to customers within the food and cosmetic industries. The productivity was 1437.5 kg dw ha−1 yr−1 (including handling space). The 10-meter vertical growth lines had an average yield of 0.29 kg dw m−1 per harvest and four partial harvests were made over a 2- year period. An economic analysis showing the cost structure of important aspects of offshore macroalgae cultivation was conducted. The total cost per kg dw of cultivated S. latissima decreased when the number of possible harvests without re-seeding was increased (from € 36.73 to € 9.27). This work has demonstrated that large-scale kelp cultivation is possible using multiple partial harvesting in the Faroe Islands, and highlighted the need for further innovation to lower the cost per unit macroalgal produced.
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The publication describes the production, properties and main applications of the three major phyco-colloids extracted from seaweed: agar, alginate and carrageenan. There is also a supplementary chapter on the preparation and marketing of seaweeds as food. Although this is based mainly as Japanese experience it is included in order to encourage increased consumption of seaweeds as human food.
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Sea cucumbers cultured in ponds or in the sea are potentially lucrative commodities, but their export value can be gained or lost through the processing used. The gutting, water temperature, cooking times, handling and drying techniques should all be carefully controlled in order to achieve the highest grade possible for export. Farmed sea cucumbers may have thinner body walls than wild animals, but have the advantage of being of consistent size, can be processed immediately after being removed from the water, and can be processed in bulk. Processors must understand the preferences of overseas importers, as desired processing approaches may vary. The use of fuel for boiling sea cucumber to make beche-de-mer can be an ecological concern. Body organs and muscle bands may offer new products for value-adding of cultured sea cucumbers. Likewise, markets are more open to fresh and canned product. Training and providing guides in the best methodologies and new market opportunities to processors present fruitful scope for improving the cost-effectiveness of farming and sea ranching tropical sea cucumbers.
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Eucheuma seaweed culture was initiated and developed in the Philippines in the late 1960's by Dr.Maxwell Doty's team. Today, Eucheuma industry has become one of the most important fishery export industries of the Philippines. Contrary to the Philippines where seaweed farming is widespread and well developed, the Pacific island countries have experienced great difficulties, both of social and economic nature in establishing the cultivation of carrageenophytes. However, the great potential of seaweed farming in rural development has motivated Pacific countries to look at the seaweed industry very seriously.
The first trial of Eucheuma culture in the South Pacific was carried out in Fiji in the mid 1970's with imported seedstock from the Philippines though this trial was not successful. In 1977 another trial of Eucheuma culture was carried out by Dr. M. Doty at Christmas Island, Kiribati. The seedstock of Eucheuma was brought from Hawaii, originally having come from the Philippines. The seed was afterward introduced to Tarawa from Christmas Island in 1981. Then, to Tonga from Tarawa in 1982, to Fiji from Tonga in 1984 and to Solomon Islands from Fiji in 1987. The first commercial shipment of 2 mt dried Eucheuma from the region was made in 1984 from Tarawa. In the region Eucheuma is currently exported from Fiji, Kiribati and Federated States of Micronesia. Culture trials are being or have been undertaken in Solomon Islands, Tonga, Tuvalu and French Polynesia.
In 1986, Fiji became the major Eucheuma growing country in the region, with 200 mt of dried Eucheuma exported in 1986 and 277 mt in 1987. However, in 1988, Eucheuma culture was totally deteriorated because of the political change that happened in the country and the sudden withdrawal of the sole Eucheuma buyer from New Zealand.
In order to overcome the marketing crisis in Fiji, most of Eucheuma buyers were contacted world-wide through the FAO network. As a result, the FMC Corporation Marine Colloids Division visited Fiji in the late 1988 and showed interest in trading the Fiji Eucheuma.
In the Pacific island context, the culture of seaweed could be beneficial for rural development. Owing to the low technology involved in farming and the small initial capital investment required, seaweed culture holds considerable promise for developing exports, providing employment, as an alternative source of income for rural fisherman and for exploiting extensive reef and lagoon areas suitable for mariculture purposes. Fiji started an arrangement of restoration programme of Eucheuma culture in 1989.
During the Second Technical Sub-committee Meeting of the Forum Fisheries Committee 16th Meeting held at Majuro in April 1989, a special meeting on seaweed culture development was organized among the Eucheuma growing and interested countries. In this meeting the countries emphasized the need for studies on marketing of dried Eucheuma, production economics and development of other potential seaweeds culture.
In response to this regional need together with aiming at promotion of Eucheuma culture in Fiji, the SPADP organized a workshop on seaweed culture and marketing for both the region and the country of Fiji, in association with the Marine Colloids Division and the Fiji Fisheries Division. The main objectives of this workshop were to:
Encourage Eucheuma seaweed culture in the Pacific region by describing and practically demonstrating appropriate culture techniques including introduction of a newly developed culture practice;
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Demonstrate baling processes and explain product quality control for the export market;
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Provide opportunities for the exchange of up-dated information, and discussion on the present situation, trends and constraints of international seaweed culture and marketing with international experts and marketing authorities.
We wish to thank the regional participants who prepared country reports, all the people of Kiuva village who accepted our field tour, for the warm-hearted and unforgettable hospitality shown to the participants, the staff of the Fiji Fisheries Division who arranged for the installation of the baling machine, the University of the South Pacific who kindly hosted the workshop, and the Marine Colloids Division's staff and the invited experts for their invaluable contribution.
It is the workshop organizer and the editor's hope that the proceedings of this workshop will be a valuable resource for both those interested in setting up seaweed farms and government officials who need to assess the prospects for seaweed farming in their countries.
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From August 18-21, 2015 Tual State Fisheries Polytechnic was pleased to host The First biannual “International Conference On Applied Marine Science and Fisheries Technology (MSFT) 2015” with main theme “Enforcing Sustainable Development of Marine Resources of Small Island”. MSFT 2015 was held in Langgur, Kei Islands, Southeast Maluku Regency, Indonesia. The Organizing Committee was pleased to note that the event gained significant interest, With over 40 National and International speakers from, Australia, United States of America, Sweden, Denmark, Malaysia, German and France and Indonesia from 22 institutions around te world as well as 31 oral presenters 18 poster presentations during 4 panel sessions. The conference hosted six keynote presentations. Dr. Zainal Arifin (Indoneisia) “Potential of Marine Pollution from Oil and Gas Industries in Eastern Indonesia and Its Prevention Efforts”, Prof. Les Christidis (Australia) presented “Incorporating diversity in aquaculture approaches as a way of future proofing the sustainable development of marine resources of small islands”, Prof. Laszlo Szekely, MD, PhD (Sweden) presented “Do we need thousand new anti-cancer drugs and can we find them in the sea?”, Assoc.Prof. Fil.Dr Tomas Cedhagen (Denmark) presented “Environmental Monitoring Through next-generation sequence Metabarcoding: Assessing The Impact of Fish Farming on bentchic macro and meiofauna communities”, Prof. Hans Glise, MD, PhD (Sweden) presented “Monetizing Marine Biodiversity for Economic Development in a Sustainable way” and Dr. Andreas Kunzmann (Germany) presented “Improving Seaweed Farmers Livelihoods Through Integrated Multitrophic Aquaculture (IMTA) and High Quality Seaweed Processing” We wish to express our gratutide to sponsors that generously assisted the work of MSFT 2015, Bank Mandiri, Bank Modern and Bank BRI. The organizing committee was delighted with the success of the conference, and wishes to note that the conference would not have occurred without the efforts of the many members of the committee, who gave generously of their time. Finally, editors have worked hard to review and edited all papers of MSFT Proceeding and we apologize if there are still any shortcoming and it will be our valuable evaluation for better work in coming years. We thank all authors and participants for their contributions.
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Net primary production (NPP) of 10 commonly available seaweeds varied from 2 to 10 g C/m3/day. The NPP of Enteromorpha compressa and Hypnea valentiae were the highest and that of Caulerpapeltata was the lowest. The mean of NPP of these 10 seaweeds when measured individually was 5.68 g C/m3/d and that of all seaweeds incubated collectively registered 5.32 g C/m3/d. Hence it is presumed that the probable rate of NPP of seaweed community contributing to Minicoy lagoon is approximately 5g/C/m3/d. Except for C.peltata E.compressa and Gelidiella acerosa. The NPP of other species was higher at bottom than at the surface of the lagoon. The results obtained are discussed in the light of distribution of seaweed in Minicoy Lagoon.
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The study analyzed the characteristics, chemical composition, and in vitro gas production kinetics of Porphyra umbilicalis and Saccharina latissima silages. Each seaweed was ensiled in vacuum bags (three bags/silage) following a 2 × 3 factorial design, with two pre-treatments (unwilted or pre-wilted) and three silage types: unwashed seaweed ensiled without additive; seaweed washed and ensiled without additive; and seaweed washed and ensiled with 4 g of formic acid (FAC) per kg seaweed. Silages were kept for 3 months in darkness at 20 °C. Pre-wilting prevented (p < 0.001) effluent formation and reduced (p ≤ 0.038) the production of NH3-N and volatile fatty acids for both seaweeds. Both pre-wilting and washing increased (p < 0.05) the ruminal degradability of P. umbilicalis silages but not of S. latissima silages. The pH of the FAC-treated silages was below 4.0, but ranged from 4.54 to 6.23 in non FAC-treated silages. DL-lactate concentrations were low (≤23.0 g/kg dry matter) and acetate was the predominant fermentation product, indicating a non-lactic fermentation. The estimated ruminal degradability of the P. umbilicalis and S. latissima silages was as average, 59.9 and 86.1% of that for high-quality rye-grass silages, respectively, indicating a medium-low nutritional value of these seaweed silages for ruminants.
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