Sunday, March 31, 2013

Aquaculture view: On the usefulness of bioenergetics and the need for more rational approaches

Aquaculture view

Aquaculture view is a column in each edition of International Aquafeed magazine (IAF), written by Dominique P Bureau.

Part of the IAF editorial panel, Dom has a PhD in Nutritional Sciences from the University of Guelph, Canada.

Today he teaches various undergraduate and graduate courses on animal nutrition and agriculture at the University of Guelph. Between 2007 and 2009, he coordinated the “Paris Semester”, a study abroad program for undergraduate students at the University of Guelph.

He serves on a number of international committees, including the US National Research Council Committee on Nutrient Requirements of Fish and Shrimp.

See all of the Aquaculture view columns here.

March - April 2013

On the usefulness of bioenergetics and the need for more rational approaches 

Bioenergetics, the study of energy transactions in biological systems, has found wide application in animal nutrition, including that of aquaculture species. A century ago, Ege and Krogh (1914) first applied the principles of bioenergetics to fishes. Today, we formulate feeds to a certain digestible energy (DE) basis and ensure that the feeds have a proper digestible protein (DP) to DE ratio (DP:DE). It is also increasingly common for feed manufacturers to alter the essential nutrient concentrations of the diet, and aquaculturists to adjust the ration to be delivered to the fish, on the basis of the DE of the feed used. Bioenergetics-driven models, such as those proposed by my mentor, Dr C Young Cho, have proven very useful and practical for estimation of feed requirement and waste outputs of fish populations held in captivity. The suitability of comparing feeds on the basis of their DE content has been demonstrated on a number of occasions in the scientific literature.

Despite its increasing acceptance and popularity in aquaculture nutrition, it must never be forgotten that bioenergetics is a ‘system’ aimed at simplifying interpretation of highly complex of biochemical processes. Hundreds of widely different compounds contain energy (Gibb's free energy). Animals do not simply metabolize this energy per se, instead, they metabolize specific nutrients, each with their specific roles and metabolic fates. Consequently, the widely held belief that ‘animals eat to meet their energy requirement’ is overly simplistic.

While it is true that animals need to consume nutrients that will be catabolized to harness their chemical energy, which will then be used in life sustaining processes, it must be recognised that a very large proportion (well over 50% under most conditions) of the feed intake of an animal is to acquire nutrients that are precursors for the biosynthesis of molecules that are structural or catalytic components (structural proteins, enzymes, phospholipids), storage forms (triglycerides, glycogen) or biologically active molecules (hormones, cytokines, lipid mediators, etc.). The amount of ‘energy’ that needs to be consumed is, thus, largely driven by 1) what the animal seeks to achieve (its growth potential, desired body composition, etc.), 2) the nutritional composition of the feed, and 3) the specific metabolic rules that govern the utilization of the individual nutrients consumed. In this context, to boil down such complex processes to a single term or factor, i.e. the ‘energy’ content of the diet or requirement of the animal, is not sensible.

Evidence suggests that significant differences exist between different aquaculture species in terms of the efficiency of different energy-yielding nutrients (amino acids, lipids, digestible starch) to support protein deposition and growth. Arguably the most significant limitation of bioenergetics models is that they are based on ‘hierarchy of energy allocation’, a concept according to which ‘growth is the surplus of energy after all other components of the energy budget have been covered or satisfied’ (Kitchell et al., 1977). This concept has proven to be a relatively flawed since young fish fed a maintenance ration (ration supporting zero body energy deposition) can still deposit protein and grow.

To quantitatively look at the requirement and utilization of all dietary components in a detailed and integrative fashion is highly desirable but it is also extremely complex. Consequently, bioenergetics offers today a relatively simple and practical way of looking at the global nutrient needs of the animal and the partitioning of these nutrients between catabolism as fuels and anabolism as storage in tissues. However, we should be unsatisfied with this situation and should strive to develop more rational approaches and models based on more or less explicit representation of biochemical reactions and metabolic roles and fates of nutrients.

A number of this type of models has been developed by various research groups for various fish species. Given the complexity of the task, all these ‘mechanistic’ models have been developed with some degree of simplification of metabolic pathways, included numerous assumptions, and been generally driven by more or less transparent and rational partitioning rules. These highly detailed models can work well within the narrow range of conditions for which they are developed. However, they generally fail to accurately describe nutrient utilization by fish under a wide range of conditions (differences in feed composition, environmental conditions, husbandry practices, life stages, genetic background of animals, etc.) encountered in fish culture.

A major bottleneck has been the lack of critical mass in terms of R&D effort invested on this topic. Efforts in the past have largely been idiosyncratic, piece-meal, and short-term in nature. There is a need for more concerted, long-term systematic R&D efforts. More comprehensive and rational approaches and models allowing more accurate description and prediction of the conversion of dietary inputs into biomass would make possible the elaboration of effective strategies aimed at improving the economical and environmental sustainability of aquaculture operations worldwide.
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Thursday, March 28, 2013

Canberrans join rush for Easter seafood

Some Easter news for you...

Canberrans are joining the annual rush for Easter seafood ahead of traditional Good Friday meals.

Retailers around Canberra are reporting high sales of fillet fish, including salmon, flathead and orange roughie as well as traditional seafood favourites of oysters and prawns.

John Fragopoulos, FishCo Downunder store owner said Easter was starting to rival Christmas for seafood sales. ''Sales on the Wednesday and Thursday before Easter will bring in as much as a normal trading week, so we have gross takings of a fortnight at Easter,'' he said.

Fragopoulos said snapper and John Dory were both selling well in recent days, but the extended prawn season was the breakout trend for Easter.

The family business has been operating in Canberra since 1997, with the Fragopoulos family involved in fishing in Australia for more than 40 years.

Bob Kearney, University of Canberra fisheries expert said the Australian industry was in excellent shape by world standards.

''Australians can eat fish this Easter with great confidence that species are well and truly sustainable and Australia's fisheries are in extraordinarily good shape,'' he said.

Anthony Fragopoulos manager of the FishCo downunder in Fyshwick holds a 30kg sampson kingfish amongst some of the other fish on offer for Easter. Photo: Colleen Petch

28/03/2013: New technology to track fish in Kenyan lakes; South Africa and Russia to cooperate on fisheries

A new technology has been launched in Kenya to track fish and help fishermen identify fish-rich areas in Lakes Turkana, Baringo, Victoria and Naivasha.
According to researchers from the Kenya Marine and Fisheries Research Institute (KeMFRI), fishermen will now be able to track fish shoals using geographical information System Maps (GISM) in the four lakes. 
Dr. Oweke Ojwang, assistant director of Kenya Artificialists Research Institute says the satellite generated maps will enable stakeholders, policymakers and fishermen to accurately identify critical fish habitats and reduce resource use conflicts.
Mr. Jones Mul, Coordinator of Lake Baringo research expedition fisheries water assessment project (LABRE) noted that the new system maps will make it easier for both fish managers and conservationists to track fish.
Speaking to Africa science news in Busia, Muli further observed that research is done to suitably manage fisheries, enhance fish production, improve livelihood and mitigate against poverty within Kenyan communities. 
South Africa’s Department of Agriculture, Forestry and Fisheries has just signed a statement of intent to cooperate on fisheries with Russia during the 5th BRICS (Brazil, Russia, India, China and South Africa) summit in Durban. Overall, nine agreements were signed by ministers from both countries to work together.

South Africa does not currently export fisheries products to Russia.

The statement signed by both parties acknowledges the importance of technical and economic collaboration among developing countries through the exchange of fisheries information, knowhow and research and its advantages for both countries, the South African Government said in a statement.

"We have to gear our energy towards ensuring that the agreements that we sign among our partners will be converted into action,” said 
Tina Joemat-Pettersson, minister of Agriculture, Forestry and Fisheries. “This agreement will be beneficial to South Africa for a number of reasons, including capacitating human capital through training opportunities and combating unregulated fishing.”
The purpose of the statement of intent is to conclude on a future agreement on cooperation in the field of fisheries based on conservation and the 'rational' use of living marine resources.

The leaders of the BRICS countries, from left: Prime Minister Manmohan Singh of India, President Xi Jinping of China, President Jacob Zuma of South Africa, President Dilma Rousseff of Brazil and President Vladimir Putin of Russia, in Durban, South Africa.

Wednesday, March 27, 2013

Reed Mariculture

Reed Mariculture is the world's largest producer of marine micro-algae concentrates. They supply algal feeds and zooplankton to universities, marine ornamental growers and over 500 fish, shrimp and shellfish hatcheries in 80+ countries worldwide. Click on image to visit website.

27/03/2013: Changes to Aquaculture Act introduced in legislation; Acoustic monitoring of Atlantic cod reveals clues to spawning behavior; Farmers face fines if ponds not registered

New amendments to the Aquaculture Act were introduced in the House of Assembly with the goal of modernising regulations. The proposed changes will strengthen regulatory and enforcement opportunities, according to a provincial government news release.

The amendments include new rules for abandoned site reclamation; enhanced industry compliance and enforcement regulations; more comprehensive definitions; new ability for ministerial refusal of aquaculture licenses if in the public interest; and introduction of mandatory licensee compliance to aquatic animal health policies.

The amendments will enable the
Minister of Fisheries and Aquaculture to require financial or other security to cover the operation and require the licensee to restore the aquaculture site to satisfaction. As well, the act will now give the minister the authority to give aquaculture inspectors the powers of peace officers when deemed necessary. 

The revised amendment will also enable ticketing and administrative penalties and provide associated regulation-making powers.

For decades researchers have recorded sounds from whales and other marine mammals, using a variety of methods including passive acoustic monitoring (PAM) to better understand how these animals use sound to interact with each other and with the environment.

Now, for the first time, researchers report using this technology to record spawning cod in the wild.

Acoustic behavior in cod has been of interest for several decades, but few studies have observed their use of sound as part of reproductive behavior. Although both sexes produce low frequency "grunts", only male Atlantic cod make this sound during spawning season. 

The findings have implications for conservation and management of this iconic species and possibly for other recreational and commercial fish species. Species in more than 100 families of fish are known to produce sounds.

According to the latest government guidelines, no person shall carry on freshwater aquaculture without registration. Farmers operating, or planning to set up, freshwater aquaculture ponds or hatcheries must now by law register their ponds.

The District Level Committee (DLC) will be the competent authority to permit fresh water aquaculture by registration. District collectors will be the chairpersons of the respective district committees and officers from irrigation, environment, ground water, agriculture, fisheries and other related departments will be the members of the district committee to monitor aquaculture ponds.

Tuesday, March 26, 2013

26/03/2013: Island fish farm makes history; A marine animal to feed your eco car

Exciting news for Canada's aquaculture industry as 24,000 young Atlantic salmon were delivered to the country's first commercial pilot facility of a land-based, closed-containment aquaculture system that has been constructed near Port McNeil by the 'Namgis First Nation.

Nanaimo's PR Aqua supplies, a world leader in the manufacture of equipment for the aquaculture industry, played an integral role in the establishment of the facility by providing almost all of the state-of-the-art equipment and technical expertise for the pilot project.

Jackie Hildering, a spokeswoman for the Namgis closed containment salmon farm, said the first harvest is scheduled in about a year and the farm should be in continual production after that. 

She added that PR Aqua supplies was chosen to provide its expertise and equipment to the project because the company meets all the technical requirements and was close to Port McNeil.  

"PR Aqua are seasoned aquaculture suppliers and the success of this pilot project would see a big boom for its business as well as the fish-farm industry on Vancouver Island."

Conservation and other groups have been advocating for years for the salmon farming industry to switch to landlocked, closed-containment systems from the open-pen systems currently operating along B.C.'s coasts.

Tunicates could be used as both biofuel and fish food. Tunicates are marine filter feeders that serve as bacteria eaters and as a foodstuff in Korea and Japan. Although not widely known, new research  suggests these filter feeders could soon become prevalent. 

Five researchers at the University of Bergen (UiB) and Uni Research have found that a certain type of tunicate -  ascidiacea- can be used as a renewable source of biofuel and fish food. This is particularly good news for the growing aquaculture industry, which for years has struggled to find enough quality feed for its fish.

 Usable as fuel
It is the cellulose, the protein and the omega-3 fatty acids in the ascidiacea that is the cause for its many uses.

"Its mantle consists of cellulose, which is a collection of sugars. When cellulose is cleaved, one can obtain ethanol. Ethanol can be used for biofuel in cars. The animal's body consists of large amounts of protein and Omega-3. This can be used for fish feed," said Eric Thompson, professor at UiB's department of biology.

Commercial potential
At the innovation conference GROW, arranged by business region Bergen, the researchers received a prize for innovative research and were awarded NOK 300,000 for their discoveries. The researchers plan to use the prize money to create commercially viable products based on their research. They have already acquired a patent for biofuel and have a patent application pending for the cultivation of ascidiacea as fish feed.

Future food and fuel? Tunicates are marine filter feeders that weigh between 50 and 70 grams and are found in all oceans. (Photo credit: Doskeland)

Event: Aquarama 2013 - 13th international ornamental fish and accessories exhibition

The 13th edition of the international ornamental fish and accessories exhibition takes place in Singapore this year at Aquarama 2013. The exhibition will take place at halls B and C of the Sands Expo and Convention Center, the Marina Bay sands.

Aquarama is Asia's biggest international ornamental fish, invertebrates, plants and accessories exhibition organised for the ornamental aquatic industry and its related sectors. It is befitting for Singapore to host the show as the number one ornamental fish exporting country which accounts for 20.3% of the world's total ornamental fish export value in 2008 (US $339.533 million). The exhibition will be co-located with Pet Asia 2013 and both shows will span an area of 8,310 sqm and house some 200 vendors from all over the world.

The show is open to the trade from 10am to 6pm on May 30 and 31, 2013 and from 10am to 1pm on June 1. Members of the public can visit the show from 1pm to 8pm on june 1 and from 10am to 7pm on June, 2013.

Adults will need to pay S$8 to visit both shows. It is free for children below 12 years of age.

The 13th annual international ornamental fish and accessories exhibition

Monday, March 25, 2013

25/03/2013: Candidates Sought for Aquaculture Innovation Award; Focus on research and regulation praised by salmon farmers

The Global Aquaculture Alliance is seeking candidates for a special award recognising innovative practices that overcome production challenges or mitigate negative environmental or social impacts at Best Aquaculture Practices-certified aquaculture farms. The inaugural Global Aquaculture Innovation Award is sponsored by Novus International.

Innovations can span the full range of farm activities, including wetlands conservation, feed management, water-quality management, effluent reduction, energy reduction, staff training, community relations, animal welfare, and health and nutrition.

Three finalists will be invited and paid by Novus to attend a semifinalist summit at the company’s St. Charles, Missouri, USA, headquarters in the summer.
The recipient of the award will receive a plaque, an all-expenses-paid trip (including airfare, registration, hotel and meal expenses) to GAA’s GOAL 2013 conference in Paris, France, and a U.S. $1,000 cash prize.
The recipient will also get the opportunity to present the innovation at GOAL 2013, in GAA’s Global Aquaculture Advocate magazine and online.

The application deadline is May 31 2013.

Federal funds earmarked for more research and better regulation will help BC’s salmon farming community and the continued protection of wild salmon stocks and habitat, said the BC Salmon Farmers Association.
“We’re glad to see the federal government focus on regulatory certainty for our farmers,” said Mary Ellen Walling, executive director. “Improvements here will not only provide more security in our sector, but will ensure that the highest standards are being set for our operations.”
The federal government released its draft 2013 budget, which included a nearly $58-million contribution to regulation, research and monitoring/reporting work for the aquaculture industry. Government also acknowledged the opportunities Canada has to be a world leader in meeting growing demands for seafood.
“It is good to see recognition from the Government of Canada of the importance of our work now and the need to maintain sustainable development into the future,” said Walling.
Since 2010, the BC salmon farming industry has been regulated under the Fisheries Act. As the act was drafted for wild fisheries, there are challenges to applying  it to aquaculture. BC’s salmon farmers have been advocating for more appropriate legislation that will provide certainty to the industry, and assurance to the general public.
“We are proud of the work our farmers are doing and the contributions they make to local communities – that can increase with the kind of attention laid out in this budget,” added Walling.

The BCSFA represents salmon farm companies and those who supply services and supplies to the industry. Salmon-farming provides for 6,000 direct and indirect jobs while contributing $800-million to the provincial economy each year.

Friday, March 22, 2013

22/03/13: Pollution threatens Chinese fish farming industry; best practices in Sri Lanka; DSM's omega-3 bottleneck

Parts of China's coastal waters are 50 percent more polluted than this time last year according to The State Oceanic Administration (SOA). The SOA found that 68,000 square kilometers had the worst official pollution rating, compared to 24,000 square kilometers on 2011. These areas are unsuitable for swimming, fish farming or port use.

A project supported by the Canadian International Food Security Research Fund (CIFSRF) is helping smallholder shrimp farmers in Sri Lanka adapt their industry’s best management practices to local needs. The resulting sustainable aquaculture practices could lead to fewer disease outbreaks, bigger and more profitable shrimp, and fewer negative environmental impacts.

Omega-3 supply crisis is not just about Peru: DSM. DSM says the supply bottleneck in fish-sourced omega-3 that recently forced its own prices up 15 percent in March, 2013, is not confined to the dominant source – Peruvian anchovies. DSM owns Ocean Nutrition Canada, which produces 70 percent of global omega-3 from its capture facility in Peru.
Northern anchovies are important prey for mari...
Northern anchovies are important prey for marine mammals and game fish Image ID: nur00009, National Undersearch Research Program (NURP) Collection Location: Pacific Ocean. Credit: OAR/National Undersea Research Program (NURP) Downloaded from: Note: Another image from this collection had fish described as northern anchovies, with the scientific name Engraulis mordax, or Californian anchovy. The species may be misidentified. (Photo credit: Wikipedia)

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Video: Ornamental aquaculture in Kenya

The Friday video this week looks at a successful ornamental operation in Kenya. Kenyans are used to eating fish, but keeping them as pets is something of a novelty. This trend is changing and there is increasing demand for species such as koi carp and goldfish.

Thursday, March 21, 2013

21/03/13: Cod and cancer; tuna aquaculture; wild salmon disease research

Researchers at the University of Maryland School of Medicine have identified a peptide, or protein, derived from Pacific cod that may inhibit prostate cancer and possibly other cancers from spreading, according to preclinical research published online in the Proceedings of the National Academy of Sciences (PNAS).
"The use of natural dietary products with anti-tumor activity is an important and emerging field of research," says senior author Hafiz Ahmed, PhD, assistant professor of biochemistry and molecular biology at the University of Maryland School of Medicine and scientist at the Institute for Marine and Environmental Technology (IMET). "Understanding how these products work could allow us to develop foods that also act as cancer therapeutics and agents for immunotherapy.
"This study is among the first to explore the therapeutic utility of a bioactive cod TFD-containing glycopeptide to inhibit prostate cancer from progressing," says Dr Ahmed.
The TFD (Thomsen-Friedenreich disaccharide) antigen in the fish protein is hidden in normal human cells but is exposed on the surface of cancer cells and is believed to play a key role in how cancer spreads. Polar fish, such as northern cod, express glycoproteins that are rich in the TFD antigen, which protect them from freezing.

Aquaculture business, Clean Seas Tuna, Australia is moving to raise $3.6 million to drive its Southern Australian yellowtail kingfish operations. The company has struggled, reporting a $34 million first half net loss but hopes for a first-ever profit in 2015.

Scientists in British Columbia, Canada are using the DNA of farmed salmon to help study the prevalence of disease in wild Pacific salmon. More than 90 percent of wild juvenile salmon die before they return to spawn. Although disease is believed to be responsible for excessive mortality, little is known about it as it is rare to see a diseased wild fish.
This is where farmed fish can help. Researchers at a joint project between Genome BC, the PSF and Fisheries and Oceans Canada are collecting tissue samples from salmon (wild and farmed, diseased and healthy) to analyse the genomes of the diseases the fish carry.

Large open water fish, like this Northern blue...
Large open water fish, like this Northern bluefin tuna, are oily fish. (Photo credit: Wikipedia)

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Stirling researchers support new entrepreneurial approach to developing sustainable aquaculture in Malawi

Aquaculture researchers from the University of Stirling are part of a major project which has received £337,000 to develop small-scale commercial aquaculture in Malawi.

Aquaculture Enterprise Malawi (AEM) is one of 15 projects just announced by the First Minister Alex Salmond to receive support from the Scottish Government’s International Development Fund through the Malawi 2013 funding round.

The three-year project brings together the Scotland Malawi Business Group with researchers from the University’s Institute of Aquaculture and the Microloan Foundation.

Together, they will work with private sector partners and existing fish farmers to develop the technical aspects of fish production, market chain communication and networking, focusing on fish farmers located in close proximity to Blantyre, Malawi’s business capital.

George Finlayson of the Scotland Malawi Business Group, a former British High Commissioner to Malawi, said, “This funding has the potential to make a significant contribution to improving nutrition and food security in and around major urban areas of Malawi.

“The demand for fish in both rural and urban areas is booming, but largely unmet. We look forward to bringing a business, microfinance and markets-based approach to producing more fish, whilst also developing the communication and networking skills of key entrepreneurial fish farmers.”

AEM aims to create and foster a supportive business environment through which a network of smaller scale fish farmers can operate as commercial stand-alone businesses, increasing the supply of farmed fish to markets and other outlets in and around urban areas in Malawi.

This project builds on the highly successful Sustainable Aquaculture Research Networks in Sub Saharan Africa (SARNISSA) project, initiated by Stirling’s Institute of Aquaculture. It established an online network of more than 2,300 people involved in African aquaculture, from fish farmers, commercial suppliers and researchers to policy makers.

William Leschen, a researcher at the Institute of Aquaculture, said, “This is an exciting opportunity to bringing a more joined-up commercial, business and markets chain approach for small-scale entrepreneurial fish farmers in Malawi.

“The Institute of Aquaculture is looking forward to playing its part in this project, offering our expertise and knowledge in aquaculture, which is now the fastest growing food production sector globally.”

The project funding announcement marks the bicentenary of Scottish missionary and explorer Dr David Livingstone, during the visit to Scotland by Her Excellency, Dr Joyce Banda, the President of the Republic of Malawi.

Fish farmer Ishamel Amadu harvests fish in Chingale, Malawi from August 2012. Photo courtesy of the WorldFish Center.

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Wednesday, March 20, 2013

20/03/13: Canada and France cooperate on macroalgae research; mapping the salmon genome

The Canadian and French governments have announced a joint study into the ability of algae to help cut greenhouse gas emissions. The two-year research project aims to determine how fast macroalgae can grow and how effectively it can absorb greenhouse gases found in typical smokestacks.

Aqua Gen and Center for Integrative Genomics (CIGENE) will collaborate with Affymetrix on a salmon genotyping data. Aqua Gen has gathered more than 900,000 markers per sample from the Atlantic salmon (Salmo salar) which can be used to make the world’s first high-density view of the marker patterns in the Atlantic salmon

English: Atlantic salmon eggs
English: Atlantic salmon eggs (Photo credit: Wikipedia)

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