During consultations related to the European Aquaculture Technology Platform (EATP) Mr Frank van Ooijen of Nutreco Holding NV drew together the major challenges facing aquaculture in the optimisation of feed for fish farming. The challenges he highlighted were:

• ensure access to raw materials in a dynamic world
• source fish meal and oil from sustainable sources
• look for independent certification
• further improve feed conversion ratios
• step up the substitution of fish meal and oil
• ensure health and safety: limit undesirable substances
• increase knowledge of fish nutritional requirements
• increase knowledge of the link between fish nutrition and fish health

The slides used by Mr van Ooijen to support his presentation may be viewed here.

Meeting the challenge of filling the fish production gap will require that aquaculture adopt ‘intensive’ production methodologies. Several industries have managed to successfully achieve this transition - one of these is the chicken meat industry. Although many of the issues that will need to be faced by the aquaculture industry will be different from chicken meat industry, there will also many that are a similar.

What is certain is that if we are to fill the fish production gap, the aquaculture industry will need to make the transition to chicken meat industry productivity and quality benchmarks in 10% of the time that the chicken industry took to achieve them. This means that aquaculture will need to have achieved the chicken meat industry metrics inside five years.

On a global scale the annual production of broiler meat is 40.5 million metric tonnes derived from approximately 48 billion birds. This volume of production is close to the projected 2030 fish production gap.

Australia’s chicken meat industry has grown from a scattered and informal adjunct to egg production into a major industry with assets in excess of $6 billion, and a turnover of $3.6 billion over the past fifty years. The industry generates 120,000 jobs through the economy, this figure including nearly 40,000 people in direct employment by the industry. Chicken meat consumption per capita in 2002/03 was 33.8kg rising to 36.5kg in 2005/06. It is poised to replace beef as the most popular meat of Australian consumers. Consumption has increased 27% over the past decade, and is expected to continue increasing at between 1-5% pa for at least the next five years. Production in 2002/03 was around 650,000 tonnes of chicken meat from 420 million birds processed. Approximately 98% of the total output goes to the domestic market. The relative price of chicken meat has fallen consistently over the past few decades, due largely to automation of processing, genetic improvements in the birds used and enlightened on-farm feeding and management practices.

Information on the current development priorities for the chicken meat industry plan can be reviewed here.

NORWEGIAN researchers in Bergen are investigating how climate change affects feed utilisation and growth in farmed salmon. Sea temperature is also said to be rising in other countries that farm Atlantic salmon in sea cages: Chile, USA, Tasmania and Ireland, meaning this is an international issue.

Salmon prefer temperatures below approximately 17C. Fish farmers have experienced that feed intake among salmon drops in such periods, the growth is reduced and the feed conversion ratio rises. In other words, they say the fish do not utilise feed as efficiently.

“In the research project, Salmon farming in warmer seawater, funded by the Research Council of Norway, we are aiming to identify how much fat and protein salmon use for growth and how much they use to maintain bodily functions when the sea is 19C. We also want to find out how higher sea temperatures affect feed conversion and feed factor,” says Ernst Morten Hevrøy, a researcher at the National Institute of Nutrition and Seafood Research (NIFES). The project is a collaboration between the Institute of Marine Research, Marine Harvest Norway, Nofima Akvaforsk/Fiskeriforskning AS, Skretting and NIFES.

“The goal is to come up with a feed whose combination of nutrients ensures the growth and wellbeing of salmon and efficient feed utilisation in warmer water. This is also important in order to ensure good fish health.”

One of the key factors that has driven the long term trend of increasing per capita fish intake across the globe is that fish consumption is promoted by nutritionists as a very important component of a healthy diet. Current thinking has targeted the Omega-3 fatty acid content of fish oils as a major contributor to the healthy diet aspects of fish eating.

Farmed fish require feed with specific protein and oil components in order to grow. Traditionally, the lion’s share of this has been derived from wild stocks of ‘feed fish’. However, even a cursory appreciation of the numbers and what we know about today’s feed conversion ratios make it apparent that it will not be sustainable to overcome the fish production gap using wild caught fish to feed farmed fish. Does the pressure on feed fish stocks mean that there is a prospect that Omega-3 fatty acids will disappear from farmed fish? Does this mean that a fundamental limiter exists that will prevent us from ever bridging the fish production gap?

Significant efforts are being made now to overcome this limiter with efforts being put into developing high protein grain-based replacements for feed fish (soy, lupins, etc). Genetically engineered plants which produce essential omega-3 fish oils could offer a new way of improving people’s diets, scientists working on an EU project said at a conference on ‘Incorporating Omega 3 in the food chain’. Long-chain fatty acids called eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA), found mainly in oily fish such as salmon, mackerel and herring, provide protection against cardiovascular diseases, slow down mental decline in the elderly and are essential for the healthy development of a baby’s brain in the womb.

Whilst experts recommend a daily intake of 450mg of omega-3 fatty acids, most adults barely manage half that amount. Among teenagers, the figure drops to just 100mg a day, and intake in low-income families is around 50mg per day less than in other families.

There are no naturally occurring plant species that have the capacity to synthesise long-chain omega-3 fatty acids. EPA and DHA are normally made by microscopic marine algae which are then eaten by small fish, passing the fatty acids into the food chain. Research conducted as part of the Lipgene project took key genes from algae and inserted them into oil seed. The results show that the plants were able to synthesise omega-3 fatty acids in their seed oils.

These outcomes show promise that GM-enhanced plant sources may be suitable suppliers of both protein and Omega-3 oils in manufactured aquaculture feed and that a sustainable route to overcoming the fish gap is potentially feasible.

More information about the Lipgene Project is available here.

We provide more resources for identifying innovation components for significant aquaculture innovation. Some examples of relevant innovation components found from these sources may be reviewed here.