no.14 - summer 2013 - skretting · in recent times. there is constant debate about whether the...

Nexus Skretting

no.14 - Summer 2013

Sanford Limited

Spirit Supreme: for local conditions

Alternative protein and energy resources

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Developing a greater knowledge of fish nutrition and applying it in feeds has contributed significantly to rais-ing the sustainability of aquaculture in Australia and New Zealand. Today the improved efficiency in the use of ma-rine resources enables the salmon farmers of our region to produce more fish protein than that used in the feed. I am pleased to add that Skretting has played an important part in this story of progress.

At the start of 2013, we are faced with the challenge of a limited fishmeal and fish oil supply, which leads to higher diet prices. These are strong incentives for further substi-tution of these raw materials. Skretting’s MicroBalance™ concept allows the production of grower feeds with much lower fishmeal contents. That means sustainably available fishmeal can be shared across the expanding aquaculture industry and fishmeal proportions can be minimised when prices peak. Our LipoBalance™ concept applies Skret-ting’s knowledge of the nutritional value of fish oils and other oils to ensure that the feeds contain optimum energy levels without depriving the fish and the consumers of adequate omega-3 content, which is an essential nutrient for both the fish and the end consumer.

In this edition of Nexus, we not only set the scene for a chal-lenging future fish oil market, but we update the direction for Skretting ARC’s fishmeal and fish oil research and we feature Sanford Ltd’s achievements with local Chinook pro-duction. Our Product Manager, Nicole Ruff, explains some exciting developments with our local Supreme salmon transfer diet range and reports on our internal research ap-plying ProtecTM to the winter production of barramundi. We are also proud to announce the appointment of Mr José Vil-lalón as the Corporate Sustainability Director for Nutreco as of April 2013.

With our corporate commitment to sustainability and feed science from Skretting ARC, I look forward to the new de-velopments Skretting will bring to the local market this year and into the future. ■

Contents

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

© All rights reserved. No part of this pub-lication 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

Cover image:Raw materials

About this issueDr Rhys Hauler Marketing Manager, Skretting Australia

Nutreco appoints a new corporate sustainability director

Fish oil market

Alternative protein and energy resources for fish feeds

Supreme confirmed as the leading transfer feed solution

Protec™ - winter specialist for barramundi

Sanford Limited

Local R&D update

Snippets

2 • Skretting Nexus Summer 2013

3

4

6

9

11

14

15

16

Nutreco is pleased to announce that effective April 7, 2013, Mr José Villalón will be appointed Cor-porate Sustainability Director.

José Villalón will be responsible for the implemen-tation of our global Sustainability Vision towards 2020 that is based on clear ambitions in the areas of people, planet and profit. This vision and the re-lated goals are an integral part of our corporate strategy for driving sustainable growth. Making sustainability an integral part of everyday business will ensure Nutreco can contribute to the Feeding the Future challenge: feeding nine billion people sustainably in 2050.

José has more than 25 years of experience in the aquaculture industry. During his career he has operated a Mexico-based consulting firm that worked with private industry on technical shrimp production protocols and farm account-ing systems, managed shrimp farms in Mexico

and he has overseen new product development and market penetration in Europe and Japan for AquaNova.

Currently, José is the Vice President and Managing Director of the World Wildlife Fund (WWF) Aqua-culture Programme. His primary role is overseeing eight multi-stakeholder roundtables, collectively called the Aquaculture Dialogues, which have created global standards that will help address the environmental and social impacts associated with aquaculture. Additionally, he manages global Aquaculture Improvement Projects which assist fish farmers to comply with those standards. He is the current Chairman of the Board of the indepen-dent Aquaculture Stewardship Council (ASC).

Knut Nesse, CEO Nutreco: “We very much wel-come José in our team and wish him every suc-cess in this position”. ■

Nutreco appoints a new corporate sustainability director

Global News

Skretting Nexus Summer 2013 • 3

Mr José Villalón Nutreco Corporate

Sustainability Director effective April 2013

Nutreco’s global sustainability Vision 2020.

See it at www.skretting.com.au

“The use of fishmeal and fish oil (reliance on small pelagic fish) is indeed one of the main chal-lenges – and sources of criticism – in the debate over the long-term sustainability of the aqua-culture industry. Regulation of wild fish catches has been driving a steady reduction in global fishmeal and fish oil production. The global aquaculture industry continues to grow, the reli-ance on fish oil for essential omega-3 fatty acids, EPA and DHA, has hit a critical point.

The catches of wild fish used in the production of fishmeal and fish oil have remained almost un-changed since the 1970s. New technology and new possibilities to monitor and identify wild fish re-sources are essential to the fishing nations’ man-agement of their marine resources. Also aware-ness about sustainable management has seen quotas and regulations enforced more strictly in recent times. There is constant debate about whether the current catch levels are sustainable, as many environmental organisations believe that a number of species are overfished. Indeed at the end of 2012, the fishing quotas set for the Peruvian fishery were reduced significantly.

Historically, half of the fishmeal and fish oil sup-ply sold on the international market to be used in aquaculture comes from Peru and Chile (Figure 1). In 2012, Peruvian producers were restricted to approximately 5 million tonnes of fish based on government regulation. This compares to approxi-mately 8 million tonnes in 2004, while in the crisis year in 2010 caused by a major El-Niño event, the total catch was approximately 3 million tonnes. The last fishing season in Peru started at the end of November 2012, and finished at the end of Janu-ary 2013 for which the fishing quota was anticipat-ed to be 2 million tonnes. With an oil yield of around 5%, this would result in 100,000 tonnes of fish oil

production from this Peruvian fishing season. However, the Peruvian quota was set at 810,000 tonnes of fish, the smallest allowance for 25 years, and limited the production of fish oil to only 40,000 tonnes, which has now caused great uncertainty of this resource as we move further into 2013.

In 2012 around 900,000 tonnes of fish oil were produced globally, of which the major fish oil man-ufacturers accounted for approximately 500,000 tonnes (Figure 2) and the remainder was made of up salmon oil (recycled oil from salmonid produc-tion) and other minor global fish oil supply. It was only in 2004 when the major fish oil manufactures produced volumes in excess of 700,000 tonnes of fish oil with aquaculture using up most of this resource and little competition from other users. Fish oil is now in serious demand due to its essen-tial omega-3 (EPA and DHA) benefits for human health, with the greatest competitive global uses of fish oil being:

• Feed for fish and other aquaculture species• Pharmaceutical industry that produces

medicines• Capsules for human consumption

Fish oil is being used increasingly in the pharma-ceutical industry to produce medicines and in the

Dr Jenna Bowyer Sustainability & Communications Officer, Skretting Australia

Demanding raw material market – the fish oil challenge


”“ Skretting ARC have focused their

effort towards improving the efficiency of EPA

and DHA in aquaculture species and researching

alternative sources of EPA and DHA other

than fish oil

supplement industry to supply fish oil capsules to consumers. The current growth in these alterna-tive sectors is estimated at 10–15% per year. These sectors are taking a larger and larger share of the global fish oil output and we now see China as a major consumer of fish oil, with their demand pre-dicted to soon overtake Western Europe. This level of competition is reflected in the market price, which has seen fish oil rise from USD$600 per tonne to USD$1,800 per tonne in the last decade (Figure 3). And now in the first half of 2013 follow-ing the fishing restrictions in Peru, the price of fish oil has reached an all-time high, with current trade around USD$2,500 per tonne!

The aquaculture industry is facing a continual glob-al reduction in the supply of EPA and DHA from fish oil. With an ever increasing price for this limited re-source, the Skretting ARC have focused their ef-fort towards improving the efficiency of EPA and DHA in aquaculture species and researching alter-native sources of EPA and DHA other than fish oil. Locally, we are exploring with our customers, oth-er alternative oil sources and further substitution levels. We are applying R&D from Skretting ARC to maximize the retention of omega-3 fatty acids in the fish flesh to ensure aquaculture species fed Skretting Australia feeds perform optimally and re-main an excellent source of omega-3. ■

Figure 2. Fish oil manufacturers for aquaculture - leading countries.

Figure 3. Price developments.

Figure 1. Landings of wild fish - leading countries.

Raw Materials


Alternative protein and energy resources for fish feedsDr Alex Obach Managing Director, Skretting Aquaculture Research Centre, Stavanger, Norway

”“land animal

proteins provide extremely good quality and safe

nutrition

Year Total production of fed species

Total of feeds used Total fishmeal used Total fish oil used

1995 4,028 7,612 1,870 463

2000 7,684 14,150 2,823 608

2010 21,201 35,371 3,670 764

Source: Tacon et al. FAO Fisheries and Aquaculture Paper 564

Table 1. Total production of fed species in 2000, 2005 and 2010, with total feed used, total fishmeal and total fish oil.

Fish feed needs high levels of protein and energy. Traditionally for carnivorous or omnivorous fish these are mainly as fishmeal and fish oil, which also contributes to the health promoting aspects of fish in the human diet.

Aquaculture today takes 60–80% of the fishmeal and 80% of the fish oil produced, mainly from the industrial pelagic fisheries and from the trim-mings produced during processing for human consumption. The industry is, therefore, heavily dependent on marine resources but production from these resources cannot be increased sus-tainably. At best, sustainably managed fisheries will continue to yield around the current harvest of 5 million tonnes of fishmeal and 1 million tonnes of fish oil. Therefore, to meet a growing demand for fish, aquaculture must identify alternatives.

RESEARCH PROGRESS

1. AminoBalance™Researchers at Skretting Aquaculture Research Centre (ARC) are looking for alternatives that will provide low feed conversion ratios, maintain high fish welfare and produce fish that are good to eat, both in terms of eating experience and nutrition. To date we have determined the nutritional value of more than 400 raw materials. These investiga-tions already led to AminoBalance™, where bal-ancing of amino acids increases the contribution such proteins make to muscle growth.

2. MicroBalance™In 2010 researchers at ARC finalised MicroBal-ance™ technology. This is based on ensuring a correct balance of several recently identified es-sential micro-nutrients in feeds. A key advantage of MicroBalance™ is the flexibility to adapt the raw material combination in response to prices, less-ening for farmers the impacts of price volatility. MicroBalance™ is now applied in the diets of sev-eral commercial species, including sea bass, sea bream, rainbow trout, turbot, and salmon.

The use of land animal proteins (LAPs) is widely used for fish feeds in countries outside of the EU, in particular Australia, Chile and Canada. LAPs provide extremely good quality and safe nutrition to supplement the other raw materials in formu-lations. Typical LAP examples in these countries include poultry meal, feather meal, mammalian meat meal and blood meal.

LAPs were banned from animal feed and fish feed in the EU following the BSE (bovine spongiform encephalopathy) cri-sis in the 1990s. In the following years, some proteins such as blood products and feather meal were re-allowed, follow-ing safety assessments. Most recently, a proposal for the full reintroduction of non-ruminant LAPs to be included in fish feeds was approved by a qualified ma-jority of EU member states and will be authorised for use in fish feed from 1 June 2013.


FISH OIL

Research to date enables Skretting to supple-ment fish oil with vegetable oils in the diets of car-nivorous species by a substantial amount, which is proven not to result in any negative effect. Much of the progress results from the EU RAFOA project — Researching Alternatives to Fish Oil in Aquacul-ture, led by the Institute of Aquaculture at the Uni-versity of Stirling, with four international partners including Skretting ARC. The project focused on four species: rainbow trout, sea bass, sea bream and Atlantic salmon. The main challenge was to maintain adequate levels of the long chain (LC) poly-unsaturated fatty acids (PUFAs), EPA and DHA, for the fish and for the health benefits of fish as food.

3. LipoBalance™ The EU AquaMax project, co-ordinated by the Norwegian National Institute of Nutrition and Sea-food Research, involving 32 international part-ners around the world including Skretting ARC, addressed this issue directly by developing diets with low levels of both fishmeal and fish oil. This complements work at Skretting ARC to develop the LipoBalance™ concept, which allows combi-nations of oils to be prepared that will provide the correct balance of energy and nutrients, including LC PUFAs, at lowest cost.

HEALTH BENEFITS

Maintaining health benefits is a key objective that is being addressed in several ways. Fish are flex-ible in that they require fatty acids for membrane structure and energy and they retain the fatty ac-ids that they need. Feeds with high levels of ma-rine ingredients provide an excess of PUFAs and a proportion is metabolised for energy, which is a waste. It is better to reduce the PUFAs and add more monounsaturated fats for energy.

At lower inclusion levels the use of these limited nutrients can be optimised, since a higher propor-tion will be retained in the muscle. At even lower levels (close to nutritional requirement) the fish can maximise its capacity to elongate and desaturate and could become a net producer of LC PUFAs.

Research at Skretting ARC into the functions of micro-ingredients led recently to a new salmon feed that significantly improves the feed conver-sion ratio and fillet yield. Fillet analysis then revealed a higher proportion of EPA and DHA than with conventional feed. The same approach is under investigation for application to rainbow trout and European sea bass.

The next step is to identify alterna-tive resources. There are two major contenders, genetic modifications to crop plants and micro-algae. Prog-ress in both is being monitored. Some plants produce PUFAs but the carbon chains are too short. The EPA carbon chain has 20 carbon atoms and DHA 22. The aim is to introduce genes to extend 18-carbon chains already present. Limited progress has been achieved with EPA. DHA is a greater challenge.”

land animal proteins provide extremely good quality and safe

nutrition

1965

0

200

400

600

800

1000

1200

1400

1600

1980 20001970 1985 20051975 19951990 2010

Aquaculture

Edible, hardening, technical use

Omega-3 industry

Figure 2. Supply and use of fish oil. Source: IFFO and Skretting Continued on page 8

Figure 1. Raw material options for fish feed. Source: Skretting

Raw Materials


Some micro-algae species are natural synthesisers of the longer chain fatty acids. The challenge here is economic; to grow them in bulk, either by sea farm-ing or in vats on land, in sufficient volumes to make them competitive as a feed ingredient. There are also reports of extracting LC PUFAs from yeast cul-tures and these would face the same economic challenge.

The task for the industry is to ensure marine ingredi-ents from the wild catch are used in a manner that spreads the benefits through a combination of sup-plementation, feed formulation and feed manage-ment on farm. This way the growing demand for fish can be met and the benefits shared sustainably for generations to come.

FEEDS IN FUTURE

Over the next ten years our focus will be very much pushing through with sustainable aquafeeds and that means increasing our knowledge of nutrition and expanding the palate of raw materials available for use in fish feeds so we are not reliant on any in-dividual raw material. Skretting will also be develop-ing a whole spectrum of diets that are very much tailored to the specific growth phase of the fish, in-cluding health promoting diets, anti-stress diets, and specialist diets for summers and winters. It is all about helping the industry to be as productive and as efficient as it can. ■

AminoBalance™Skretting’s AminoBalance™

concept is based on balancing the essential amino acids to increase the contribution of feed proteins to

make fish muscle growth.

MicroBalanceTM

Skretting’s MicroBalance™ uses knowledge of the function of micronutrients that allows flexibility to adapt raw material combinations in response to market prices, lessening feed price volatility.

LipoBalance™Skretting’s LipoBalance™ uses knowledge of oil sources to provide the correct balance of energy and nutrients levels in feeds to achieve the optimal level of omega-3 in fully grown fish.

”“

Raw Materials

fillet analysis

revealed a higher proportion

of EPA and DHA than with conventional

feed

continued from page 7

Dr Alex Obach Managing Director,

Skretting Aquaculture Research Centre


New Zealand based seafood company Sanford Limited was established in 1881 and listed as a public company in 1904. The company has sev-eral branches across New Zealand involved in the capture, culture, processing and exporting of high-quality fish and aquaculture products.

Sanford has been farming Chinook salmon in New Zealand for 31 years. The salmon grow-out sites are situated in Big Glory Bay, Stewart Island, New Zealand’s southernmost inhabited island. With a population of only 400 people, 85% of Stewart Is-land’s 1680 km2 is a national park. Sanford has five licences for salmon grow-out, of which two are used at any one time. Operating the salmon farm are 18 farm staff including shift workers, harvesting crew, divers, an engineer and management staff. The majority of the staff live on the mainland in In-vercargill, while seven of the staff live on Stewart Island.

Sanford produces salmon all year round and this is achieved with three smolt inputs per year. Around 1.5 million eggs are produced and fry are reared across three hatcheries, Kaitangata, Waitaki (both Sanford owned), or Salmon Smolt NZ (a coopera-tive hatchery). Once the fry reach 20-25g they are transported to Big Glory Bay and on-grown for ap-proximately 2 years until they reach a harvest size of around 4kg. In 2012, Sanford produced 3500 tonnes of Chinook salmon, all of which were pro-cessed at Sanford’s Bluff factory and the majority was then exported to markets all around the world.

Stewart Island is an isolated location, with chal-lenging weather and the often wild waters of Fo-veaux Strait standing between it and the mainland. Fortunately this doesn’t bother the Salmon Farm Manager at Sanford, Alan MacDonald, who origi-nates from the equally remote and maritime Isle of Tiree in the Inner Hebrides of Scotland. Alan has been salmon farming for 15 years and has been working for Sanford since 2007.

Farm Profile

Continued on page 10

Ben Wybourne New Zealand Technical Account Manager, Skretting Australia

Sanford Limited - Sustainable Seafood with MicroBalanceTM

A panoramic view of the site at

Stewart Island


During his career, Alan has witnessed the prog-ress of the salmon industry in reducing its reli-ance on volatile marine raw materials derived from a finite resource. Since the introduction of Skretting’s MicroBalanceTM in diets for Chinook salmon in 2011, Sanford has reduced the level of fishmeal in their diets from 25% to 8%. This has allowed them to become net fish protein and fish oil producers (Figure 1).

Skretting invests heavily in sustainable busi-ness practices for both economic and envi-ronmental reasons. Ben Wybourne, Technical Account Manager for Skretting Australia, com-mented that “the introduction and continuing success of the MicroBalanceTM concept in di-ets for Chinook salmon is very satisfying. Ad-ditionally, we have proven that we are able to use alternative sources to reduce the level of fishmeal in diets without detrimentally affecting fish growth, health or quality.”

Over the past five years Sanford has started in-vesting in a selective breeding program. Alan MacDonald says “The first selected smolt will be introduced this year and one of the traits we are selecting for is faster growth”. This next step in combination with the success of the MicroBalanceTM concept will ensure the con-tinued growth and sustainability of the Chinook salmon industry in New Zealand. ■

”“we are able

to use alternative sources to reduce

the level of fishmeal in diets without detri-mentally affecting fish

growth, health or quality

Farm Profile

Continued from page 9

0

0.3

0.6

0.9

1.2

1.5

NZ Chinook 1990 pressed pelletsNZ Chinook Early extruded diets (1998-2002)Sanford 25% FM 9mmSanford 15% FM 9mmSanford MicroBalance 8% FM 9mm0

0.3

0.6

0.9

1.2

1.5

Pressed pellets(1990)

25% fishmeal

9mm

Early extruded

diets (1998-2002)

15% fishmeal

9mm

MicroBalance™ 8% fishmeal

9mm

Fis

h p

rote

in p

rod

uc

tion

(kg

ou

t pe

r kg

in)

Figure 1. Historical and current trends in the net marine (fish) protein production in diets fed to Sanford’s chinook salmon.

Sanford Salmon Farm Manager Alan

MacDonald


”“In Australia, Skretting’s pre- and post-transfer diet for salmon smolt, Nu-tra Supreme (freshwater) and Spirit Supreme (seawater) have been used successfully since 2010.

Nutra Supreme and Spirit Su-preme were developed by researchers at the Skretting Aquaculture Research Centre (ARC) in Norway specifically to prepare Atlantic salmon smolt for transfer to seawater and then to sup-port the fish as they adapt to the new con-ditions. Part of the ingredients package is a range of health supporting micro-ingredients. The nutri-tional combination provides fish that are more ro-bust to withstand stress and possible disease out-breaks. Importantly, better adaptation means rapid and increased feed intake after seawater transfer and therefore growth.

Supreme has also been adapted for local chal-lenges; namely for use during periods of high temperature and to better prepare smolt for their first-time exposure to amoebic gill disease (AGD) in newly transferred fish.

SUPREME - THE CONCEPT

The relationship between micro-in-gredients and their importance for

fish health and growth has been a major focus at Skretting ARC in re-cent years. The work has provided a wealth of knowledge of the benefi-cial ways in which micro-ingredients

can be used and this knowledge has been implemented in the transfer di-

ets.

Supreme diets contain a micro-ingredient solution which produces physiological effects en-abling fish to better handle the transition to seawa-ter. They also contain the elements from Skretting’s proactive diet, ProtecTM, to help smolts withstand all potential challenges at transfer.

Laboratory experiments carried out by Skretting ARC consistently demonstrated positive differenc-es through use of the new transfer feed concept. The researchers looked directly at the influence on the physiology of smoltification, growth and feed intake. Experiments as well as commercial expe-rience have shown that fish fed these transfer di-ets thrive better after transfer to seawater. Growth

Supreme diets contain

a micro-ingredient solution enabling

fish to better handle the transition to

seawater

Continued on page 12

Supreme confirmed as the leading transfer feed solution

Product Update

Dr Nicole Ruff Product Manager, Skretting Australia


”“ Supreme fed fish had

achieved a higher average weight and a lower FCR

rate was higher in each test and, maximum feed intake (Rmax) was reached much earlier in Su-preme fed fish. The graph below shows results from one such experiment (Figure 1). In this case the Supreme fed fish consistently ate more dur-ing the first 35 days at sea, reaching the expect-ed feed intake two weeks earlier than the control fish. This shorter period to Rmax post-transfer has considerable implications which pay off later in production (shorter time to harvest or bigger fish at the same harvest time).

The advantages of Nutra Supreme and Spirit Su-preme have also been demonstrated under com-mercial conditions, positioning it as the leading transfer diet available on the market.

SUPREME - PROVEN ON FARM

Recent full scale farm trials were run in Scotland from autumn 2011 to spring 2012, with impressive results. The trials involved fish sourced from both tank and cage sites. In all cases improvements in feed conversion ratio (FCR) and growth rate were recorded.

Increased feed intake is hard to measure during the first days in seawater, but when the fish were sample-weighed for the first time Supreme fed fish had achieved a higher average weight and a lower FCR. This indicates that, where Supreme diets were used, the fish consumed more of the feed offered. In fact, the reduction in feed wastage and associated increase in growth during the initial period at sea was shown in most cases to be suf-ficient to cover the investment of using Supreme.

SUPREME - MORE AT HARVEST

Getting fish off to the best start means that they stay ahead right through to harvest. For example, one of the trials showed a 10% increase in growth rate and a 17% improvement in FCR over the first 107 days at sea.

Based on the commercial performance an in-crease of between 150g and 200g can be ex-pected at harvest.

0%

0.5%

1.0%

1.5%

2.0%

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35

Sta

nd

ard

fee

d ra

te (%

BW

/d)

Days post-transfer

01 179 257 2113 29 333 1911 277 2315 31 35

0.5

1.0

1.5

2.0Spirit Supreme

Control

Figure 1. Feed intake for fish fed Spirit Supreme vs control diet post-transfer to seawater.

Continued from page 11

Product Update


”

SUPREME - INTRODUCING 2 NEW UPGRADES

Nutra/Spirit Supreme HT for High Temperature

Smolt transfers happen over a wide range of months and through very different environmental conditions. In Tasmania, for example, the earliest smolt transfers take place in late summer, some-times at warm water temperatures. For these fish we recommend Nutra/Spirit Supreme HT, which is a combination of the transfer support as well as high temperature concept developed for fish entering the sea into water temperatures above 15oC.

Nutra/Spirit Supreme GT for AGD Management

Functional ingredients have recently been docu-mented to improve survival of salmon challenged with AGD (see Nexus issues 12 and 13) and sub-sequently these have been included in the new Nutra/Spirit Supreme GT. This is an exciting con-cept considering that trials with these feeds were conducted around the transfer phase of the fish and benefits were documented in naïve fish when exposed to amoeba for the first time. This diet will help prevent reduced feed intake that can occur as the amoeba infection progresses and also de-lay the requirement for the first bathe to treat AGD, ensuring smolt get off to the best possible start.

SUPREME - EFFICIENT IN TRANSFER SUPPORT OF CHINOOK SALMON

The complex process of smoltification has not only been described for Atlantic salmon, but also for Chinook salmon. There is evidence from North American enhancement hatcheries that feeding Nutra/Spirit Supreme provides valuable support when transferring Chinook smolt.

Amongst the reported benefits were synchroni-sation of smoltification timing and reduction of re-sidualisation (many groups have high coefficient of variation (CV’s, specifically length) and so are at different states of smoltification at release). More-over, behavioural changes have been observed when using Supreme, with fish displaying calmer behaviour at release, indicating they had better handled the stress of transfer compared to other fish not fed the Supreme diets.

HOW TO USE SUPREME FEEDS

Nutra Supreme and Spirit Supreme must be used on each side of seawater transfer to return the full set of potential benefits.

The recommended regime is for Nutra Supreme to be fed five to six weeks before and Spirit Su-preme to be fed five to six weeks after seawater transfer. When water temperatures are lower they should be used for a week longer to ensure opti-mal performance.

Following Spirit Supreme, Spirit Plus 100, followed by Spirit Plus 500 are used. This maintains the Spirit concept of fastest growth to 1000g body weight. ■

Skretting Australia Atlantic salmon Active Nutrition range, which now include HT and GT additions

Hatchery Diets Smolt Diets Grower Diets

Optimal NutritionNormal conditions

Nutra XPNutra RC

Spirit Plus 100Spirit Plus 500

Optiline X/XE 1000Optiline X/XE 2000Optiline X/XE 3000

Proactive NutritionPrepare for stress and disease

Protec™ RCProtec™ 100Protec™ 500

Protec™ 1000

Specific NutritionEnvironment

Nutra Supreme HTNutra Supreme GT

Spirit Supreme HTSpirit Supreme GT

Spirit Plus HT 100Spirit Plus HT 500

Optiline HT 1000Optiline HT 2000Optiline HT 3000S

altw

ate

r tra

nsf

erNutra Supreme Spirit Supreme

Product Update


During the winter months species such as bar-ramundi commonly have reduced appetite as a result of the cold water temperatures. In turn this leads to a loss of growth and condition, and vulner-ability to diseases or an inability to handle stress-ful events. Protec™ has a proven track record in imparting improved fish performance during sub-optimal water temperature. Its benefits have been demonstrated in field trials in Italy and Spain and more recently here in Australia.

In Australia, the benefits of using Protec™ as a diet strategy to mitigate the effects of winter in barra-mundi was tested. The trial consisted of six smaller enclosures all housed within the same pond. Pro-tec™ was fed to half of the enclosures while our standard ration, Nova, was fed to the remaining half and acted as the control. Barramundi were fed from early June until September, a total period of 98 days. Despite water temperatures already dropping below 24oC at the beginning of the tri-als, the final results demonstrated the ability for Protec™ fed barramundi to better perform under the conditions. The Protec™ fed barramundi had a marginally improved feed rate, specific growth rate (SGR), and feed conversion ratio compared to the control diet (Table 1.)

At the conclusion of the trial the barramundi were also assessed for their ability to handle a stressful event, and again it became clear that the use of

Protec™ was of benefit. Glucose and lactate (sec-ondary stress parameters) were measured, and for both indices barramundi fed the control diet had 30% more of these circulating stress param-eters compared to those fed Protec™ (Figure 1 a, b), signifying improved stress resistance. Finally an assessment of liver vitamin E (alpha-tocopherol) showed that Protec™ fed barramundi had close to double the concentration of this vitamin in their livers compared with the control group (Figure 2). As a powerful antioxidant, not only would this have helped over the winter period but it would place these fish in good stead as they recover during the spring.

Protec™ is available as both a sinking and floating pellet. For winter feeding we recommend feeding approximately 4 weeks prior to the onset of sub-optimal water temperatures and during the entire winter period. For further information contact Dr Nicole Ruff, Product Manager ([email protected]). ■

Figure 1. Relative % increase (compared to basal concentrations) in a) glucose and b) lactate in barramundi fed a control diet or ProtecTM following a stress event.

Control Control ControlProtecTM ProtecTM ProtecTM

Figure 2. Liver vitamin E concentrations (IU/kg) of barramundi fed either ProtecTM or a control diet for several months.

1 0 3

26 35 7

51 70 12

75 105 16

100 140 20

% G

luc

ose

inc

rea

se (f

rom

b

asa

l leve

ls p

re-s

tre

ss)

% L

ac

tate

inc

rea

se (f

rom

b

asa

l le

vels

pre

-str

ess

)

Live

r vita

min

E (I

U/k

g)

Strengthens the immune system

Increases antioxidative capacity

Improves gut health

Antimicrobial effect

1

26

51

75

100

Series10

35

70

105

140

Series13

7

12

16

20

Series1

1a 1b

Dr Matthew Bransden Technical Account Manager, Skretting Australia

- winter specialist for barramundi

Local R&D Update

Performance indicator Change

Feed rate 3% increase

Specific growth rate (SGR) 6% increase

Food conversion ration (FCR) 6% decrease

Table 1. Difference in performance parameters in barramundi fed ProtecTM or a control diet over the winter period.


In the previous issues of Nexus, we presented you with the results of the effect of immunostimulating and immunosupporting feeds on fish when chal-lenged with AGD. As mentioned previously, the tri-als with these feeds were conducted around the transfer phase of the fish and benefits were doc-umented in naïve fish when exposed to amoeba for the first time (see Nexus issues 11 and 12). The study was the first anywhere to demonstrate that diet manipulation can play an active role in reduc-ing mortality caused by AGD.

Since then, a semi-commercial trial on large fish (5kg) was conducted between September 2012 and January 2013. The purpose of this trial was to establish whether the concept proven in naïve fish could also be effective in animals infected by and treated for AGD numerous times in their life at sea. Fish were fed the proven test diet or a control diet (standard commercial feed). At the termina-

tion of the trial, fish were generally in good AGD- condition and no major difference was detected between dietary treatments with regards to gill scores. However, over the trial period of 113 days, fish fed the test diet had 22% better growth com-pared to the control fed fish (Figure 1). This in itself is interesting since reduced feed intake generally occurs as the amoeba infection progresses.

Following on from our previously successful trial last year on naïve fish, a second challenge trial with naïve fish is planned for March this year. Fish will be fed further refined experimental diets and then challenged with the amoeba. The progression of AGD will be evaluated in order to see if we can fur-ther reduce the impact of AGD on fish exposed to the amoeba for the first time. Any delay in the onset of AGD post transfer is going to be of major benefit to the performance of the fish as well as the man-agement of AGD further down the track. ■

Figure 1. Weight gain (kg) in Atlantic salmon fed a control diet or test diet.

Control

We

igh

t ga

in (k

g)

0.5

0.9

1.3

1.6

2.0

Test diet

”“ fish fed

the test diet had 22% better growth

compared to the control fed fish

0.5

0.9

1.3

1.6

2.0

Strengthens the immune system

Increases antioxidative capacity

Improves gut health

Antimicrobial effect

Dr Nicole Ruff Product Manager, Skretting Australia

Skretting Australia AGD research update

Local R&D Update


In November, the 5th annual New Zealand Aquaculture conference was held in Nelson. Skretting Austra-lia was a silver sponsor of this confer-ence. The event was themed around Sustainable Growth.

There was a range of speakers from across NZ and around the world dis-cussing value enhancement, innova-tion, law, sustainability, health, market development, Maori business, invest-ment, the global economy and of course there was some great sea-food on offer. ■

New Zealand Aquaculture Conference November 2012

Skretting World Aquaculture Conference, Adelaide, 2014

Low oxygen researchInvestment in total environmental control is en-abling Skretting researchers to investigate ways of counteracting the effects of low levels of dissolved oxygen in seawater. The latest trials are identifying options to minimise these impacts through adjust-ed feeding regimes and feed formulations. At the Skretting Aquaculture Research Centre (ARC) the Lerang Fish Trials Station has had a re-cent upgrade. The flow rate of seawater through the tanks can be controlled and with this, so can the amount of dissolved oxygen in that water. ARC Researcher Guido Riesen explains, “Our aim is to minimise the impact of low oxygen conditions on growth performance by adjusting feeding in-tensity and, for example, the energy levels in the diet. Low dissolved oxygen environments oc-cur in a wide range of aquaculture systems and the change can be quite sudden. We believe the current phase of climate change will increase the frequency of low oxygen conditions, especially in the semi-enclosed coastal areas often used for aquaculture. It is well known that fish in low oxygen environments lose appetite, which leads to lower growth and impacts profitability. Those effects are well described in research literature but there is surprisingly little information on what to do about it.”

Vibeke Vikeså, another ARC Researcher, investi-gated the effects of low and variable oxygen lev-els on large Atlantic salmon, grown from 1.3 kg to 3.6 kg. “I found a 12% reduction in specific growth rate and a 10% reduction in feed intake. The feed conversion ratio increased by 5% and both protein and fat retention were reduced. The physiologi-cal balance was also affected, for example, there were detectable signs of an decreased ability to take up oxygen.” In the next stage of her PhD re-search, in cooperation with NIFES — the National Institute of Research on Nutrition and Seafood — Vikeså will be looking at how nutrients are utilised by Atlantic salmon under the combined effects of at high temperature and low oxygen conditions. ■

On June 7-11, 2014, the Skretting World Aquaculture Conference and Trade Show will be held at the Adelaide Con-vention Centre, South Australia.

Australia will be hosting the World Aquaculture Conference for the first time since 1999. The event will com-bine the international annual conference and the biennial Aus-tralasian Aquaculture Conference into one event.

This conference is expected to attract several thousand local and international visitors to our doorstop for the largest primary industries conference and trade show to be held in the Asia Pacific region for some years. Watch this space for further up-dates as the event draws closer.

Also for more information visit: http://aquaculture.org.au/ ■

ARC R&D Update

Snippets


http://aquaculture.org.au

http://www.skretting.com.au

no.14 - summer 2013 - skretting · in recent times. there is constant debate about whether the...

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