No. 25 - Summer 2016/2017 - The magazine of Skretting Australia

NUTERRA

OILS FOR FISH AND HUMAN HEALTH

Our global sustainability programme

SKRETTING

www.skrett ing.com.au

Nexus

™ Skretting Australia is holding its second AquaScience forum this July. Our ambition is to share with you the latest global knowledge available from our researchers at Skretting Aquaculture Research Centre, guest scientists and industry professionals to help you to continue to grow an economic and sustainable aquaculture business.AquaScience will be held in Hobart on Tuesday 25th July, and Christchurch on Thursday 27th July.

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SUMMER DIET DEVELOPMENT

page 3

NUTERRA - GLOBAL SUSTAINABILITY PROGRAMME

page 5

FISH OIL AND AQUACULTURE GROWTH

page 8

WHAT ARE YOU GROWING?

page 10

CONTENTS

Email: jenna.bowyer@skretting.com

Nexus is published by Skretting and is distributed free to all our customers involved in the Australian and New Zealand Fish Farming Industry.

© All rights reserved. No part of this publication may be reproduced without the prior written permission of the publishers.

This publication is not intended to remove the need to take advice when dealing with specific situations and readers should contact the editor before taking any action in reliance on the articles in Nexus.

Contact Information:26 Maxwells Road Cambridge Tasmania Australia 7170PO Box 117 Rosny Park Tasmania Australia 7018Telephone: +61 3 6216 1201

Welcome to the first Nexus edition of 2017.

Our last Nexus focussed closely on the details of our R&D portfolio. We announced that our long

wait to run controlled experiments using large salmon at high temperature was over and we were

gearing up to run our first experiment at the new Experimental Aquaculture Facility (EAF) at Taroona.

We are following this up in the current issue and have some really exciting results to share from

the first trial. While we are currently experiencing a cooler summer in the salmon farming regions of

Australasia, we are working hard to bring new innovations to the table for next summer.

With such a focus on R&D in the last edition, we thought it appropriate that this edition takes a step

back and we look at some of our bigger picture issues and activities.

We have been closely following the future supplies of fish oil and we feature the need and future

sources of the nutrients that we currently get from fish oil. We are discussing the science behind

growing fish for optimal growth and that a better understanding of what happens to feed nutrients

after they are eaten can give a better understanding of the nutrient balance in the feed.

Lastly, this edition is introducing Skretting’s new global sustainability programme, Nuterra. Skretting

will be re-branding the existing SEA program to Nuterra, but the core principals remain the same.

The Nuterra programme provides the tools required to implement our sustainability strategy

throughout the company. Sustainability - It’s not just what we aspire to do, it’s what we do. n

Skretting Australia will be releasing some new publications in the coming months, including our 2016 Sustainability Report and the 2016 Residue Report. Keep an eye on our website for more information.

While we are currently experiencing a cooler summer in the salmon farming regions of Australasia, we are working hard to bring new innovations to the table for next summerLeo Nankervis Marketing ManagerSkretting Australia

DR LEO NANKERVIS MARKETING MANAGER

About this issue

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TRIAL RESULTS

At the conclusion of the trial late in 2016, salmon

performance was assessed. Fish size over the

experimental period increased by an average of ~1.2

kg. Over the trial period, fish fed Diets C and D had

a significantly better feed rate compared to fish fed

the control Diet A. For Diet C, this translated into

significantly improved growth compared to the control

feed, whilst all feeds resulted in similar feed conversion

ratios (Figure 2, over page).

“The outcome of our first trial in the EAF is very

pleasing” says Nicole Ruff, Product Manager for

Skretting Australia. “The fish performed well and

both growth and feed conversion exceeded typical

commercial expectations for fish of similar size under

prolonged high temperature exposure.”

This would partly be a reflection of the experimental

system wherein fish are slightly overfed and all

uneaten food is captured, which means performance

parameters can be calculated very accurately.

However, it may also be an indication of the true

potential of these fish at higher temperatures.

AN EXCELLENT START

In our last edition of Nexus we proudly showcased the

newly built Experimental Aquaculture Facility (EAF) at

the Institute of Marine and Antarctic Studies (IMAS),

Taroona. Since then we have run our first trial, which

investigated several new feed concepts designed to

improve the growth of large Atlantic salmon at high

temperature. We have been eagerly awaiting the

opportunity to test new diet concepts, so we spread

the net wide to get a broad feel for what feed can do

to improve salmon production during summer.

The fish for the experiment were received from

SALTAS in October 2015 and had been on-grown

successfully in the EAF stock tanks from smolt size

to approximately 1.4 kg. In April 2016, the fish were

stocked into the 7,000 L tanks. Following stocking

and acclimation, the groups of salmon were fed 3 test

diets (Diet B, C and D), which were compared against

a control feed (Diet A). Initially the fish were held at

15°C for four weeks, followed by a temperature

increase to 19°C, which was maintained for a further

10 weeks.

Figure 1. Schematic of trial design. 7000L triplicate tanks were stocked with 50 fish per tank. Fish were fed 4 different diets

1380 - 2620 g

4 weeks 10 days 10 weeks

15 - 19˚C15˚C 19˚C

DR RHYS HAULER COMMERCIAL MANAGER

Summer diet development at the EAF

Continued over page

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A NEW SUMMER DIET ON THE HORIZON

Apart from this overall positive outcome it is even

more pleasing to see that diet can further improve

the performance of fish held under these challenging

conditions. The improved growth of salmon fed two

of the experimental feeds, particularly Diet C, is very

promising.

“We are very excited by the result and are looking

forward to offering a new feed solution for our

customers’ summer feeding strategies going forward”,

says Nicole. “Final diet validation and further refinement

will be tested in our next high temperature trial at the

EAF which will commence in a couple of months. Solid

documentation will put us in an excellent position to

launch a new summer feed in the last quarter of 2017.”

SYSTEM PERFORMANCE

“As the manager of the EAF, I am very happy with how

the first full scale trial in the large experimental system

went”, explains Polly Hilder. “Fish behaviour was

excellent and apart from some minor teething problems,

the system performed very well”.

The system has the ability to tightly control environmental

parameters, particularly temperture and oxygen. This,

combined with strict feed management protocols and

accurate feed intake data, allows for great confidence in

the experimental outcomes.

“Research, as displayed in Skretting’s first trial, provides

important information to the Atlantic salmon industry

tackling climate change and culture of fish in warmer

summer waters”, says Polly. “We look forward to ongoing

trials and the continued expansion of knowledge that will

assist the production of Atlantic salmon in Tasmania.” n

5 SKRETTING

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0.50

0.54

0.58

0.62

A B C D

1.00

1.20

1.40

1.60

1.80

A B C D

0.70

0.80

0.90

1.00

A B C D

SGR

(%bw

/day

)FC

R (g

/g)

SFR

(%)

a

*

* *

b

c

Figure 2. (a) specific growth rate (SGR, %bw/day), (b) feed conversion ratio (FCR, g/g) and (c) specific feed rate (SFR, %) of 2.6 kg Atlantic salmon at the end of the high temperature feed trial. * Denotes a significant difference compared to the control Diet A (t-test, p<0.05)

Solid documentation will put us in an

excellent position to launch a new summer feed in the last quarter

of 2017Dr Nicole Ruff

Product ManagerSkretting Australia

Facilities at the EAF

6 SKRETTING NEXUS

Through our insight as a global leader in the animal nutrition and aquaculture feed sectors, Nutreco has long held the opinion that using resources in increasingly efficient and innovative ways is the most sustainable approach to feeding the growing population. It is also apparent to us that integration of the latest technological developments into pioneering, practical nutritional solutions can have a significant impact on closing the gap between the current productivity of livestock and aquaculture species and their actual genetic potential. Equally, we support new farming practices that seek to optimise production rather than those methods that simply seek to maximise output to the detriment of the broader landscape. At the same time, to ensure that our innovations can reach their full potential, we believe it is essential that we maintain open communications with all stakeholders.

While these are very noble aspirations, we know they would be of no value and that we couldn’t hope to make an important contribution to solving the food production challenge without a strong company-wide focus on sustainable innovation.

Therefore, Nuterra – our new global sustainability programme – has been designed to live up to our responsibilities and considerable ambitions.

COMMON GOALS

With its crucial role in the aquaculture supply chain, Skretting has long put sustainability at the heart of its operations and has been heavily engaged in efforts designed to make the aquaculture industry as a whole become more sustainably viable. Indeed, right up to the point of launching Nuterra, this commitment to sustainability was successfully expressed through the Sustainable Economic Aquafeeds (SEA) programme, which identified the key sustainability issues facing the aquaculture industry and the actions Skretting was taking to address them.

“What Nuterra does is progress the sustainability agenda further still – not only within Skretting, but across the entire Nutreco business. Sustainability has been a common pillar for both the animal nutrition and aquaculture sides of the company for a long time, but most of the actual sustainability efforts in these fields have been independent actions. Even though some challenges are specific to animal nutrition and some to aquaculture, the core issues of food and feed production are the same. Essentially, Nuterra brings all our knowledge and expertise together and aligns our activities into a common, coordinated programme to move forward more efficiently and effectively,” says Trygve Berg-Lea, Sustainability Manager at Skretting.

DR JENNA BOWYER SUSTAINABILITY & COMMUNICATIONS OFFICER

The sustainability of food production is one of the greatest global challenges of our time. In the coming decades, the world will need to produce as much as 70% more food than at present to feed a population that is forecast to exceed 9 billion people by 2050, while we – as a population – are currently using the equivalent of 1.5 planets to support our way of life.

Nuterra: a united approach to sustainability

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THREE-PRONGED STRATEGY

The Nuterra Programme sets out Nutreco’s sustainability strategy and provides the tools required to implement this throughout the company. Made up of three distinct components: the Nuterra Roadmap, the Nuterra Standard and the Nuterra Product Assessment, the programme provides a more holistic approach to sustainability than Nutreco has had previously, explains Berg-Lea.

“It is designed to show us collectively where we need to put more emphasis in terms of common sustainability challenges such as climate change, and protecting life on land and in the water. It also indicates where we need to get stronger commitments both in the wider value chain and from our own teams,” he says. “Whereas historically, one of our main focuses was on the responsible use of finite marine resources, Nuterra is a more balanced programme requiring that we fully evaluate the bigger picture of such a challenge.”

The Nuterra Roadmap sets clear ambitions regarding people, planet and profit. It is an aspirational tool designed to align the company’s actions and initiatives over a period of several years. These objectives are allied with the long-term strategy goals and are built on the

programme’s four pillars: Nutritional Solutions, Ingredients, Operations and Commitment.

The Nuterra Standard is an internal tool that clearly outlines the actions needed to realise the Nuterra Roadmap, as well as to measure and score progress over time. Nutreco companies are to undertake this assessment biannually to ensure accountability in sustainability aspirations and targets.

“Having a system where you can clearly express your policies and your goals makes it much more tangible for all our teams. It encourages engagement, which leads to the identification of any ‘sustainability gaps’ and then to efforts to close those gaps. The Nuterra Standard enables our organisation to work with sustainability in much more structured and efficient ways. It also makes a major contribution to governance in this area,” says Berg-Lea.

Last but not least, the Nuterra Product Assessment is a tool that helps measure the environmental impacts and attributes of Nutreco’s nutritional solutions. It uses Life Cycle Assessment methodology to systematically evaluate the environmental aspects of using these products and services. The process of identifying what the most important sustainability attributes will be for aquaculture feeds is underway.

™

Nuterra brings all our knowledge and expertise together

and aligns our activities into a

common, coordinated programme to

move forward more efficiently and

effectively Trygve Berg-LeaSustainability Manager

Skretting

8 SKRETTING NEXUS

UNITED NATIONS ALIGNMENT

Nutreco’s Nuterra Programme is also a good fit with many of the 17 Sustainable Development Goals (SDGs) to be achieved by 2030 that were adopted by 193 United Nations (UN) member states in September 2015, highlights Berg-Lea.

“The second SDG – ‘End hunger, achieve food security and improved nutrition and promote sustainable agriculture’ – is very much aligned with our mission of ‘Feeding the Future’. Looking ahead, we will continue with our commitments to develop nutritional solutions and contribute to feeding a growing global population, while also reducing our environmental impact.”

Within the Nuterra Roadmap, Nutritional Solutions focuses on helping animal and farmer to perform better. Through the development of nutritional solutions, Nutreco expects to make a significant contribution to making aquaculture production more sustainable. In this regard, the focus is on four innovation areas: LifeStart, Feed Efficiency, Animal Health & Welfare, and Models & Services.

LifeStart covers specific hatchery and nursery nutrition, nutritional solutions for challenging first life stages, transition diets and broodstock nutrition.

Feed Efficiency focuses on having the knowledge and competence to meet all of the nutritional requirements of aquaculture species in order to fully utilise its growth potential. This will enable us to maximise the output of body mass (food) for a given input of feed.

Animal Health & Welfare concentrates on supporting fish and shrimp stocks against stresses such as extreme temperatures, handling and a range of parasites and diseases that can lead to negative health impacts.

Models & Services support our customers to choose feeds that best suit their unique situations and to provide advice to deliver optimum on-farm performance and maximise return on investment.

As Skretting’s aquaculture diets comprise a wide variety of ingredients sourced from all over the world, the Ingredients component of the Nuterra Roadmap creates a sustainable base for feeds and includes responsible sourcing as well as the progression of sustainable partnerships between value chain partners, says Berg-Lea.

The Nutreco Supplier Code of Conduct enables engagement with suppliers on material issues relating to their operations and to set minimum criteria relating to environmental, social and legal aspects. Based on spend, over 90% of suppliers have signed-off on their agreement to comply with the code, and it is mandatory for all new suppliers to sign. Supplier sustainability audits are performed, with an extra focus on countries and ingredients that have been identified as ‘high-risk’.

At the same time, because cooperation between value chain partners (business, government, science and NGOs) is a prerequisite to successfully addressing the sustainability challenges of the industry, Nutreco participates in various sustainable partnerships such as the Round Table on Responsible Soy, the ProTerra Network, the Roundtable on Sustainable Palm Oil, the Aquaculture Stewardship Council and the International Fishmeal and Fish Oil Responsible Supply Standard.

Meanwhile, the three goals: SDG 13 ‘Take urgent action to combat climate change and its impacts’; SDG 14 ‘Conserve and sustainably use the oceans, seas and marine resources for sustainable development’; and SDG 15 ‘Protect, restore and promote sustainable use of terrestrial ecosystems, sustainably manage forests, combat desertification, and halt and reverse land degradation and halt biodiversity loss’ are comparable with Nuterra’s ambition to protect life on land and in the water, he says.

“The higher ambitions in the Nuterra Roadmap aim to ensure that responsible ingredients can be sourced without damaging life in the water or on the land, while still enabling Nutreco to

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The Operations area ensures Nutreco has its own house in order by focusing on reducing the environmental impact of operations as well as improvements within the working environment. Under the Nuterra Programme, the focus is on the monitoring and recording of five sustainability KPIs. Targets are set for each of these and results are discussed as efforts progress.

Energy – Make smarter decisions about using newer, more energy efficient equipment and processes in our factories.

CO2 Emissions – Continuously investigate options to change our energy sources to more sustainable options.

Waste – Aim to reduce the amount of waste going to landfill by recycling and reusing as much as possible. Also focus on reducing the amount of products we purchase that cannot be reused or recycled.

Water – Lower withdrawals from local water sources by increasing productivity per water input, reducing wastewater discharges and their pollutant load, and reducing thermal energy consumption.

Health & Safety – Monitor our health and safety performance by registering work accidents and by continuously improving the safety of our work environment.

While innovations and operational best practice are hugely important elements in the progress of sustainability, Nutreco believes the agenda can only be meaningfully progressed through communication and dialogue with stakeholders.

As well as hosting the two biennial conferences, AgriVision and AquaVision, that bring together key stakeholders from the international feed-to-food chain to discuss global feed, food and business related topics, Nutreco is also heavily involved in community development. This is through the recognition that many farmers in developing markets are smallholders, using basic agriculture and aquaculture methods.

The company has also identified that an important component in the global challenge of sustainably feeding a growing population is to improve the productivity and sustainability of these farms’ farming methods. Therefore, through local community development programmes and partnerships with local governments, NGOs, universities and other companies, Nutreco is sharing its knowledge and expertise. Current programmes include a project in Nigeria helping to raise the livelihoods of as many as 1,000 small catfish farmers.

continue to play a key role in the expansion of sustainable food production for many years to come.”

Over the coming months, the team at Skretting Australia will be communicating more about our Nuterra programme, including the pending publication of our 2016 Skretting Australia

Sustainability Report. n

For more information now, please visit our website

www.skretting.com/en-AU/sustainability

10 SKRETTING NEXUS

Fish oil: is this the

limit to industry growth?

For many people the compelling argument to eat fish is its health benefits. From brain and eye development to anti-inflammatory and cardiovascular health, the benefits of the oils ingested through eating fish are many. One of the greatest ironies is that this could also be one of the limits to the growth of the aquaculture industry.DR LEO NANKERVIS MARKETING MANAGER

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CURRENT STATUS

Global fish oil production has not increased for the last 15

years, while farmed fish volumes have increased by more

than 25% over the same period (IFFO/FAO). This growth

has been possible by firstly taking up a larger proportion of

global fish oil supply and secondly by reducing the amount

of fish oil in aquaculture feeds.

Skretting is proud to have been at the forefront of oil

nutrition research for more than 20 years, without which fish

oil would have already imposed a ceiling on aquaculture

growth. Alternative oils have production benefits for fish,

many of them providing valuable energy in a more digestible

form than fish oil, which increases growth and improves the

conversion of feed into fish.

Better feed conversion means a more sustainable use of

feed resources, which combines with improved measures

such as fish in to fish out ratio (FIFO) to further support the

environmental credentials of aquaculture. Despite a more

rational use of fish oil, strong industry growth dictates that

fish feeds are currently the direct destination for the majority

of the world’s fish oil supply. With little prospect of increasing

fish oil volumes into the future we must ask ourselves how

we expect our industry to continue to grow while maintaining

current levels of the health promoting fatty acids EPA and

DHA in fish flesh. The answer may be found by looking

further down the food chain.

ALGAE OILS

We could be forgiven for thinking that fish oil is the source of

omega-3 fatty acids in the marine food chain, but the reality

is that fish and other vertebrates are incapable of producing

large amounts of these fatty acids. The actual source is from

marine microalgae, and it is the tendency of fish to mimic

the fatty acid profile of its diet that leads to fish oil being

such a rich source of the marine omega-3 fatty acids EPA

and DHA. Fish oil is really a reflection of the microalgae oil

content at the base of the food web.

The technology to grow microalgae to produce omega-3

fatty acids has been available for some time, but it has

not been until recently that the continued expansion of

the aquaculture industry and concurrent demands on

fish oil have prompted increased interest in its large-scale

production. While this technology may never produce

the fatty acids that we need at today’s fish oil prices, our

increasing demand on fish oil as a limited commodity is likely

to force its price upwards.

If we are to remove fish oil supply as a limitation to

aquaculture growth, while still maintaining the human health

benefits of eating fish, marine algae present an appealing

opportunity. This opportunity is fast becoming a reality, with

our aquaculture customers having the opportunity to invest

in the future of fish feeds and incorporating algae oil in fish

feed formulations in 2017.

Very low

Low

Moderate

High

Figure 1: Blood EPA and DHA levels were compiled from published literature and used to map status by country (Stark et al. (2016) Progress in Lipid Research, 63: 132-152).

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ALTERNATIVE SOURCES OF EPA AND DHA

While algae oils are closing on commercial reality, the

future may hold further choices in marine omega-3 fatty

acid supply. The alternative approach to growing algae

directly comes through identifying the genes responsible

for production of EPA and DHA from non-marine oils and

their translocation into existing oil crops. This approach

was pioneered by the CSIRO and is being commercialised

through their collaboration with NuSeed and the Grains

Research and Development Corporation (GRDC).

When commercialised, the resultant canola crop has the

potential to produce high quality oil, rich in the essential

omega-3 fatty acid DHA, and at a large scale. While

genetically modified (GM) products continue to polarise

consumer populations, published consumer surveys

indicate that the consumer health benefits of additional

marine omega-3 in fish could positively influence the

discussion against the negative implications of GM.

HEALTH BENEFITS OF EATING FISH

The health benefits of eating fish are broader than its fatty

acid composition alone. The FAO consider that vitamins A

and D, selenium, iodine, phosphorous, magnesium are all

additional benefits of fish consumption, in addition to being

an easily digestible source of protein.

Despite this, it is the fatty acid profile that receives the

most attention and is best documented in terms of human

health benefits. Despite conjecture about relative merits of

total omega-3 fatty acids or omega-3:omega-6 ratios, the

fact remains that it is EPA and DHA that have been well

documented to deliver health benefits and suboptimal intake

of these fatty acids is linked to decreased cardiovascular

health and cognitive decline.

Consumption of fish or fish oil supplements provides

humans with the majority of EPA and DHA in our diets, yet

we still do not get enough. A large proportion of the world’s

population, including Australia and New Zealand, tend to

consume low levels of EPA and DHA, as highlighted by

a recent review of blood analysis data (Stark et al. 2016;

Figure 1). This is a compelling argument to eat more fish,

but possibly also to supply the market with fish containing

higher levels of EPA and DHA.

THE FUTURE

Last year, Skretting announced the world’s first commercial

salmon feeds that were completely free of fish meal or other

marine proteins. Now, with the addition of algae oil, we

take one step closer to total independence from fish raw

materials. Fish meal and oil are likely to remain important

ingredients into the future, but the ability to make feeds

independent of their use gives us the freedom to grow. n

Sources ofEPA +DHA

Algae

Fish oil

GM crops

Alternative oils have production benefits for fish, many of them providing valuable energy in a more digestible form than fish oil, which increases growth and improves the conversion of feed into fishDr Leo NankervisMarketing ManagerSkretting Australia

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From its very first mouthful of food, it is critical that fish receive an optimal balance

of nutrients in order to meet their growth potential and

maintain optimal health. We deliver these nutrients in the

form of extruded fish feed pellets. The path from feed

to growth is not direct, and a better understanding of what

happens to feed nutrients after they are eaten can give a better understanding of the nutrient balance in the feed.

Feed to fish: the path to optimal growth

First, let’s start at the end product. The composition of the whole fish

at harvest size is the growth target in aquaculture. It may be the fillet

or flesh that the end consumer is interested in, but when we grow

fish we need to take into account the whole body and what each

component of the fish requires for optimal growth. All of the fish organ

systems are critical for growth and require nutrient input for optimal

growth, health and quality.

The frame for growth comes in the form of a skeleton, which sets

the potential for fish length (Figure 1). Healthy bones require the

correct balance of minerals, which has been a focus of our research

for decades, optimising the scope for growth, but also minimising

rates of malformation. The skeleton also forms a structure for muscle

attachment, and is therefore literally the architecture upon which the

fillet forms.

It is easy to assume that we are growing protein, since fish are

considered to be a meat product. In actual fact fatty fish such as

salmon have considerably more whole body fat than protein (Figure

2). Even relatively lean fish such as yellowtail contain a similar

proportion of fat and protein. Given these figures, it may come as

a surprise that fish feeds generally contain much more protein than

fat. After all, the body composition should represent the nutrients

used for growth. The simple fact is that protein growth is an inefficient

process and utilisation of proteins for energy even more so.

DR LEO NANKERVIS MARKETING MANAGER

14 SKRETTING NEXUS

Proteins are complex molecules and require several digestive steps

to release the amino acids that are absorbed from the gut into fish

blood. These are referred to as absorbed nutrients, while those that

are not absorbed are lost as faecal nutrients (Figure 3).

Absorbed amino acids are reconstructed according to the genetic

code of the proteins that the fish needs to grow, contributing to

growth or retained nutrients. Those that are not retained are broken

down for energy and result in dissolved losses of ammonia. Both of

these processes consume significant energy, in fact protein growth

is estimated to consume 15% of the energy contained within those

proteins (Blaxter 1989).

Deriving energy from protein is even less efficient, resulting in 35%

losses when converted into body fat. In contrast, the fat component

of feeds is not only very digestible, but the conversion of dietary fat

to body fat is approximately 96% energy efficient. This means that

dietary fat is a much more efficient means of delivering the energy

that is so important in optimising growth and feed conversion, while

excess protein results in elevated energy losses and less efficient

production.

If fish are consuming more energy they also consume more oxygen.

We tested this theory recently with our feed and showed that fish

consume considerably more oxygen when given a high protein feed

when compared to fish given an optimally balanced protein diet,

despite being fed the same amount and growing at a similar rate

(Figure 4).

It is important to provide fish with enough digestible protein to

support optimal growth, but above this level, energy is more

efficiently provided by dietary fat. Skretting feeds are optimised

according to extensive research into nutrient requirements at various

stages of fish growth, providing an optimal balance of protein, fat

and energy in order to grow fish most efficiently at the least cost of

production. n

Figure 1. X-ray image of a fish skeleton. Image courtesy Professor Eckhard Witten

Blaxter, K., 1989. Energy metabolism in animals and man. Cambridge University Press, Cambridge, UK

Dietary fat is a much more efficient means of delivering the energy that is so important in optimising growth and feed conversion, while excess protein results in elevated energy losses and less efficient productionLeo NankervisMarketing ManagerSkretting Australia

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Figure 2. Harvest size Atlantic salmon (left) and yellowtail kingfish (right) whole body composition

Figure 3. Nutrient balance in fish nutrition

Ash

Protein

Fat

Moisture

Figure 4. Oxygen demand of trout fed iso-energetic feeds with different protein content

(mg/

h)

Our sustainability programmeIt’s not just what we aspire to do, it’s what we do

The sustainability challenges of food production are both significant and intensifying. In the coming decades, the world will need to produce as much as 70% more food to feed a growing world population. At the same time, farmers face ever-greater consumer demands. Through our focus on sustainable innovation we aspire to be part of the solution. As an aqua feed company with a global presence, we are ideally positioned to contribute towards the development of more sustainable food production. Nuterra, our global sustainability programme, is designed to live up to our responsibilities

and ambitions. Read more at www.skretting.com.au-en/sustainability

™