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January | February 2014EXPERT TOPIC - SHRIMP
The International magazine for the aquaculture feed industry
International Aquafeed is published six times a year by Perendale Publishers Ltd of the United Kingdom.All data is published in good faith, based on information received, and while every care is taken to prevent inaccuracies,the publishers accept no liability for any errors or omissions or for the consequences of action taken on the basis ofinformation published.Copyright 2014 Perendale Publishers Ltd. All rights reserved. No part of this publication may be reproduced in any formor by any means without prior permission of the copyright owner. Printed by Perendale Publishers Ltd. ISSN: 1464-0058
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F ISH FARMING TECHNOLOGY
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Welcome to Expert Topic. Each issue will take an in-depth lookat a particular species and how its feed is managed.
SHRIMP
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Global
EMS Impact on globalshrimp industry and
future prospectsby Dr Farshad Shishehchian, presidentand CEO of Blue Aqua International andpresident-elect of the Asia Pacific Chapterof the World Aquaculture Society
The early mortality syndrome (EMS)
in shrimp has been ravaging pro-
duction systems, spreading verti-
cally in Asia and horizontally to
countries as far away as Mexico since first
reported in 2009.
Looking at the impact of EMS on the three
largest global shrimp producers Thailand,
Vietnam and China - there have been sub-
stantial effects on supply and prices to the
global shrimp market.
"Thailand used to be the largest shrimp
exporter with over 500,000 metric tonnes of
shrimp production.
"In 2013, its production fell almost 50 per-
cent from the previous year because of EMS.
This offers a window of opportunity for other
potential shrimp producers such as Indonesia,India and Ecuador. Indonesia farmers have
experienced the highest profit record in their
shrimp history as a result.
"Culture expansion is putting in full force
during this lucrative period. India is another
potential producer to
keep an eye on. Since the
permission of vannamei
culture a few years back,
India increased its shrimp
production by more than
two fold last year. Ecuadoris pushing with much high-
er production in the past
two years."
In conclusion, and due
to the impact of EMS, Dr
Shishehchia says shrimp
prices will continue their
high level for some time
because of the insufficient
supply.
"This is likely to con-
tinue until Thailand, the
worlds leading shrimp
exporter and most tech-
nologically advanced pro-
ducer, gets into recovery
mode and creates a shift in supply and prices."
However, the long-term impact will be
consolidation and integration of shrimp farms.
The current disease situation and environ-
ment will push for consolidation in the mar-
ket. Small farms without aquaculture practice
standards and sufficient funds will be driven
out of the business. Those large farms with
strong finance, good farm management, lowcost, high access to markets will be the future
of the shrimp industry, he adds.
EMS ForumAsian Aquaculture Network (AAN), in
corporation with International Aquafeed
and the Association of International
Seafood Professionals is organising a EMS
Forum: 'Managing the Shrimp Epidemic' in
terms of bringing practical solutions to the
shrimp industry. The forum will be held on
March 28-29, 2014 at KU Home, Kasetsart
University, Bangkok, Thailand. This event
is supported by Department Fisheries ofThailand, Department Fisheries of Indonesia,
Shrimp Club of Indonesia (SCI) and Blue Aqua
International. Participants are expected from
India, Vietnam, Malaysia and Mexico in addi-
tion to Indonesia and Thailand.
Dr Farshad Shishehchian President and CEO of BlueAqua International and President-elect of the AsiaPacific Chapter of the World Aquaculture Society
(right) with Tuti Tan of International Aquafeedmagazine, Roger Gilbert President of Association
of Sdeafood Professionals and publisher of IAF andNun Chongwitookit, Marketing Communications
at Blue Aqua International during the APA13exhibition in Ho Chi Minh City, Vietnam in
December 2013
January-February 2014 | INTERNATIONAL AQUAFEED| 43
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Biofloc systemsUsing super-intensivebiofloc systems for Pacificwhite shrimp production
by Tzachi Samocha, Terryl Hanson,
Timothy Morris, Vitalina Magalhes, BobAdvent and Andr Braga, Texas A&MAgriLife Research Mariculture Lab, FlourBluff, Texas, USA
The demand for protein by an
increasing world population
together with decreasing harvests
from fisheries has resulted in
rapid growth of aquaculture. Global aquac-
ulture currently accounts for 40 percent of
seafood production and provides 60 percent
of shrimp demand. The world shrimp farmingindustrys annual growth over the last decade
has been estimated at 10 percent. The rapid
expansion of this industry has stimulated the
intensification of production systems, which
has unfortunately resulted in the release
of nutrients and organic waste, and some-
times the spread of diseases, all damaging
receiving streams. Uncontrolled growth has
imposed heavy losses, and raised major
criticisms that threaten further development
of the industry. To reduce losses to disease
outbreaks, producers have been looking
for more sustainable and cost-effective
practices.
Despite the world trend in favour of
aquaculture, in the United States the sector
has shown no substantial growth. The country
thus remains a net seafood importer, with
annual shrimp imports of 1.2 billion lbs
worth $4.5 billion. New approaches must
be devised if US shrimp farming is to avoid
the environmental drawbacks of traditional
flow-through ponds. US systems must have
a very low impact on the environment andfully contain rather than export any
water quality or disease problems that
arise. One approach is to shift from low-
intensity outdoor ponds to super-intensive
indoor recirculating aquaculture systems
(RAS). With little or even
no water exchange, properly
managed RAS thus reduces
or eliminates the amount of
nutrients released to the envi-
ronment, escape of non-native
culture species, and spread
of pathogens to the environ-
ment. Because of these factors
they easily conform to effluent
standards set by the national
regulator.
Biofloc technology (BFT)
systems are a special type of
RAS that maintain a commu-
nity of suspended (flocculated)
microalgae and autotrophic
and heterotrophic bacteria
(biofloc) together with the
shrimp in limited-exchange
grow-out units. Pacific white
shrimp (Litopenaeus vanna-
mei) growth rates are muchhigher in BFT systems than
in clear-water systems, and higher still at
greater floc levels. The composition of the
biofloc affects nutrient cycling. Heterotrophs
and autotrophs are preferred in floc systems
because they provide two very important
services: they assimilate ammonia and nitrite
(both highly deleterious to shrimp), and act as
a supplemental feed.
Biofloc success: a water
quality issue?Feed and feeding practices are importantfactors affecting water quality and profit-
ability of any aquaculture operation, moreso
when dealing with hyper-intensive, biofloc-
dominated systems. As mentioned above,
shrimp can derive nutritional benefits from the
microbial aggregates in BFT systems. Studies in
our lab also showed good shrimp growth (2.4
g per week) and survival (96.8 percent) when
5 percent of the fishmeal in a 35 percent
crude protein diet was replaced with biofloc.
However, this replacement resulted in a
reduction in shrimp growth (0.4 g per week)
compared to the control diet with no f ishmeal
replacement. Analysis of the biofloc produced
in our system suggested low protein (20.4
percent), low fat (0.29 percent) and high ash
(43.4 percent) content.
Because feed represents one of the major
costs in shrimp production, accounting for
over 50 percent of the total production costs,
it can significantly affect profitability. The
interactions between feed, water quality and
productivity have been evaluated in relation
to the characteristics of each culture system
resulting in the development of specially
designed feeds to enhance shrimp perform-
ance in each system.
The effects of commercial feeds on water
quality and shrimp performance are important
factors affecting feed formulations. The end
product of feed catabolism is ammonia, which
can be toxic to shrimp. Ebeling et al. describe
three pathways for ammonia removal in tradi-
tional aquaculture systems: photoautotrophic,
autotrophic and heterotrophic. The dominant
of these pathways in BFT systems can be
affected by biotic and abiotic factors.
With an adequate supply of organic
carbon, heterotrophic bacteria can quickly
convert (in around 8 hours) all available
ammonia into bacterial biomass, a process
which requires a large amount of oxygen and
the generation of high volume of bacterial
biomass. On the other hand, when organic
carbon is provided solely from feed, any
ammonia not consumed by the heterotrophic
bacteria will be slowly converted into nitrate
by autotrophic bacteria. This nitrification proc-
Table 1. Litopenaeus vannamei performance in a 92-d grow-out trial in four 40 m3RWs stocked with juveniles (1.2 g) at adensity of 530/m3and operated with no water exchange
IDWt(g)
Growth(g/wk)
Yield(kg/m3)
Sur.(%)
FCRWater Use
(L/kgShrimp)
ST 18.45a 1.27 8.96 84.4 1.28 148
FF 17.35b 1.26 8.24 80.2 1.35 149
* Values with different superscript letters indicate stat
Table 2. Summary of a 108-d grow-out study performed in2009 with juveniles (0.99 g) Litopenaeus vannamei stocked at450/m3 under no water exchange
Tank ID
Av.Wt.
Growth Survival YieldFCR
O2Usage
(g) (g/wk) (%) (kg/m3) (LPM)*
RW (ST) 21.88 1.37 94.5 9.43 1.58 0.17
RW (FF) 22.45 1.37 96.6 9.63 1.55 0.27
Table 3. Combined mean production values from two grow-out studies conducted in 2011 withjuveniles Litopenaeus vannamei from Fast-Growth (a) and Taura resistant lines (b) in the 40 m3 andthe 100 m3 raceways.
System
Volume
NDensity
(shrimp/m3)
Salinity
(ppt)
Initial
Wt. (g)
Final
Wt. (g)
DaysGrowth
(g/wk)
Sur.
(%)
Yield
(kg/m3)
FCR
40 m3 4 500a 18 1.9 23.2 82 1.82 82.3 9.5 1.43
40 m3 1 500a 30 1.4 25.1 85 1.95 78.9 9.9 1.44
100 m3 2 390b 30 3.1 25.3 106 1.46 83.0 8.4 1.77
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ess, which consumes alkalinity as an inorganic
carbon source, requires far less oxygen and
produces around 40 times less bacterial bio-
mass than the heterotrophic pathway. When
operating biofloc systems under low light
intensity with restricted organic carbon supply,
autotrophic and heterotrophic bacteria will
dominate the microbial populations. These
mixotrophic systems require careful monitor-
ing and control of selected water quality to
maximise production.
2007-2011: early studiesIn recent years, studies at the Texas
A&M AgriLife Research Mariculture Lab have
focused on the use of a commercial feed
made by Zeigler Bros. (HI-35, Zeigler Bros.,
Gardners, PA) formulated for use in high-
density, biofloc-dominated no-exchange sys-
tems for the production of market-size L.
vannamei. These studies were conducted in
four to six greenhouse-enclosed 40 m3/68.5
m2raceways. Each lined raceway is equipped
with a centre longitudinal partition positioned
over a 5.1 cm PVC pipe with spray nozzles.
Every tank had six banks of three 5.1 cm airlift
pumps positioned equidistantly on each side
of the partition. In addition, each raceway had
six 0.91 cm long air diffusers, a 2 hp centrifugal
pump, and a Venturi injector capable of intro-
ducing atmospheric air or a mixture of oxygen
and air. The following is a short summary of
the progress made in operating this system
over the last six years.
The 2007 study was conducted in four of
the raceways described above, which were
equipped with the YSI 5200 inline dissolved
oxygen monitoring system. The tanks were
stocked to a density of 530/m3 with 1.2 g
juveniles using water from a 77-day nursery
trial. The study compared two methods of
biofloc control: homemade foam fractionators
and settling tanks. Shrimp were fed on the
HI-35 feed mentioned above. Until Day 73
(estimated 7 kg shrimp/m3), oxygen demand
was met solely by the Venturi injector and
atmospheric air. From Day 74 on, atmos-
pheric air was enriched with pure oxygen.
The dissolved oxygen monitoring system was
instrumental in managing feed and preventing
low oxygen events. All shrimp submitted for
disease diagnosis showed no signs of viral
infections. The results from this trial are sum-
marized in Table 1.
In 2009 a second study was conducted to
determine whether or not smaller commercial
foam fractionators (in the case, Aquatic Eco
Figure 1: Ammonia-N (100 m3 RWs) Figure 2: NO2-N (100 m3 RWs) Figure 3: NO3-N (100 m3 RWs)
Figure 4: Alkalinity (100 m3 RWs) Figure 5: Turbidity (100 m3 RWs) Figure 6: TSS (100 m3 RWs)
Figure 7: VSS (100 m3 RWs) Figure 8: SS (100 m3 RWs)
January-February 2014 | INTERNATIONAL AQUAFEED| 45
EXPERT TPIC
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Vietnam, with its population base of 90 million people, produces for domestic markets and export marketsUS$6.7 billion of farmed fish products. Of its exports 21 percent goes to the EU, 19 percent to the USAand 16 percent to Japan. Currently, Vietnam exports 40 percent of its shrimp production and 30 percentof its Pangasius. Vietnam is aiming at achieving food security in fish by 2020. The industry faces challengesin the area of disease, production costs, meeting market requirements, financial resources and value chaindevelopments. This conference aims to address several of theseissues for producers and marketers. www.en.vietfish.com.vn
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Systems VL65 fractionator) could be used
to minimise the differences in shrimp final
weights observed in the 2007 study. The 108-
day study was conducted in the same four 40
m3 raceway tanks equipped with the previ-
ously described YSI 5200 dissolved oxygen
monitoring system. Raceways were filled with
water from a preceding 62-day nursery study,
and stocked to a density of 450/m3with 0.99
g juveniles. Freshwater was added weekly to
offset water losses. Shrimp were fed the same
HI-35 feed mentioned earlier. Settling tanks
and the foam fractionators were operated
intermittently, targeting total suspended solids
concentrations between 400 and 600 mg/L.
The results showed no significant differences
in shrimp final weights between the raceways
operated with settling tanks and those oper-
ated with foam fractionators. Furthermore, no
statistically significant differences were found
in shrimp performance between treatments
(see Table 2).
In an effort to reduce production costs(e.g. the use of pure oxygen and electricity)
the lab began to test non-Venturi injectors for
aeration and mixing in two 100 m3raceways
under biofloc conditions. These injectors (a3,
All Aqua Aeration) are currently used in
several wastewater treatment facilities in the
United States and require little maintenance
compared to other aeration and oxygenation
methods. This technology may be successfully
transferred to biofloc and other types of aqua-
culture systems. Based on the manufacturers
specifications, the injector provides a 3:1air-to-water ratio, compared with the 6 kg/m3). Each
tank was equipped
with 14 injectors,
and one injector
powering a home-
made foam frac-
tionator for biofloc
control. Raceways
were stocked to a
density of 270/m3
with 8.5 g juveniles
and were fed the
Zeigler Bros. HI-35
feed. At the end
of the 87 days of
the 2010 trial, a
yield of 6.4 kg/m3
was obtained from
marketable shrimp
(26.1 g), with 90.1
percent survival
rate and a feedconversion ratio of
2.46.
The trial in 2011
was conducted
in five of the 40
m3 raceway tanks
described above,
filled with a mixture
of seawater and biofloc-rich water previously
used in a 42-day nursery trial. Salinity in four of
the tanks was adjusted to 18 parts per thou-
sand using chlorinated municipal freshwater.Raceways were stocked to a density of 500
shrimp/m3with 1.90 g juveniles. For compari-
son, a fifth tank was operated with salinity of
30 parts per thousand, and stocked with 1.40
g juveniles stocked at a density of 500/
m3. All raceways were stocked with
shrimp from a Fast-Growth line provid-
ed by the Oceanic Institute, Makapuu
Point, Hawaii. Shrimp were fed the
same HI-35 feed as in previous studies.
The raceways were operated with no
water exchange throughout the study.
Results from this study showed high
yields of food size shrimp, with good
growth, survival and FCR (see Table 3).
The second 2011 trial was conduct-
ed in the two 100 m3 EPDM rubber-
lined raceways, each filled with a mix-
ture of seawater, municipal chlorinated
freshwater, and biofloc-rich water from
a previous nursery study. The tanks
were stocked with 390 shrimp per
m3, with Taura-resistant L. vannamei
juveniles (1.90 g) supplied by Shrimp
Improvement System, Florida. Shrimpwere fed the same HI-35 feed used
in previous studies. Raceways were
equipped with the YSI 5200 dissolved
oxygen monitoring systems and were
maintained with no water exchange
throughout the 106-day duration of the study.
The results are summarised in Table 4.
2012: trials point tocommercial viabilityThe studies in 2012 used both systems for
the production of marketable shrimp. The first
study was conducted in six 40 m3 raceways
and had four objectives:
1. Evaluate the effect of two commercial
feeds on juvenile shrimp produced
from a cross between Fast-Growth and
Taura-Resistant lines
2. Monitor the changes in selected water
quality indicators under no exchange
3. Monitor L. vannamei performance under
high density and no exchange
4. Evaluate the benefit of using the YSI
5500 continuous dissolved oxygen
monitoring system with optical probe
in operating a biofloc-dominated, super-
intensive shrimp production system
The second study took place in the two 100
m3raceway tanks and had three objectives:
1. Evaluate the performance of the same
juvenile shrimp used in the previous
study under the same stocking den-
sity when fed the HI-35 feed under no
exchange2. Further evaluate the ability of the a3
injectors to maintain adequate mix-
ing and dissolved oxygen levels in a
high-density, biofloc-dominated, zero-
exchange conditions
Table 4. Summary of mean final weight, weekly growth, yield, survival,FCR, and water usage from a 67-d grow-out study of Litopenaeus
vannamei in 40 m3 greenhouse-enclosed raceways operated with nowater exchange.
FeedYield Survival Av. Wt. Growth
FCRWater Use
(kg/m3) (%) (g) (g/wk) (L/kg shrimp)
HI-351 9.74 87.3% 22.12 2.03 1.25 124.7
SI-352 8.71 88.3% 19.74 1.76 1.43 138.3
Diff 1.03 2.38 0.27 0.18 13.6
1RWs where shrimp were fed the HI-35 Zeigler Bros. feed2RWs where shrimp were fed the SI-35 Zeigler Bros. feed
Table 5. Summary of Litopenaeus vannamei) performance following a63-d grow-out period in two 100 m3raceways using the a3 injectors formixing and aeration.
RW
Stocking Harvest Growth Survival Yield
FCR
Water
Use(L/1 kg)(Juveniles/m3)(g) (g) (g/wk) (%) (kg/m3)
1 500 3.6 22.76 2.13 80.82 9.20 1.43 139.5
2 500 3.6 22.67 2.12 78.19 8.86 1.53 148.9
Average 22.72 2.12 79.50 9.03 1.48 144.2
Table 6. Summary of production and sales forsuper-intensive biofloc dominated no exchangeshrimp production systems comparing the resultsfrom the 2011 trial to the 2012 trials.
Treatment 2011HI-3540 m3
SI-3540 m3
HI-35100m3
Stocking density(Juvenile/m3)
5005000%
5000%
5000%
Survival rate(%)
81.687.3
+7.0%88.2
+8.1%79.5-2.6%
Growth rate(g/wk)
1.852.03
+9.7%1.76-4.9%
2.13+15.1%
Stocking size(g)
1.82.7
+50%2.7
+50%3.6
+100%
Harvest size(g)
23.622.3-5.5%
19.8-16.1%
22.7-3.8%
FCR 1.431.25
-12.6%1.430%
1.48+3.5%
Crop length(days)
8367
-19.3%67
-19.3%63
-24.1%
Production(kg/m3)
9.589.74
+1.7%8.71-9.1%
9.03-5.7%
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3. Evaluate the benefit of using the YSI 5200
continuous dissolved oxygen monitoring
system in operating the system
We also aimed at reducing FCRs below
the values achieved in the previous trials,
primarily through continuous feeding.
The six 40 m3 raceway tanks were filled
with a mixture of water used in a preceding
49-day nursery study, seawater and municipal
freshwater to reach a salinity of 30 parts
per thousand. Each tank was equipped with
a small commercial foam fractionator and a
homemade settling tank. Shrimp used in this
study were produced from a cross between
Taura-resistant and Fast-Growth genetic lines
developed by Shrimp Improvement Systems.
Raceways were stocked with 2.66 g juveniles
at a density of 500 shrimp/m3. The study was
performed with three replicates using a semi-
intensive feed (SI-35) which had 35 percent
crude protein, 7 percent lipid and 4 percent
fibre, and a hyper-intensive feed (HI-35) with
35 percent crude protein, 7 percent lipidand only 2 percent fibre, both produced by
Zeigler Bros.
The raceway tanks were maintained with
no exchange throughout the study and fresh-
water was added to compensate for water
losses. Oxygen supplementation was initiated
on Day 17 and continued until termination.
The YSI 5500 monitors and their optical
probes allowed trouble-free, real-time oxygen
supplementation
while avoid-
ing excess use.
Concentrations
of total ammo-
nia-nitrogen
remained
below 0.5 mg/L
throughout the
study, while
NO2-N level
remained below
1.22 mg/L with
no significant
differences
between treat-
ments. While solids were controlled by the
use of the foam fractionators and settling
tanks, levels of total suspended solids, turbid-
ity and volatile suspended solids levels in the
SI treatment remained significantly higher
than the HI treatment. These results may be
related to the higher levels of non-digestiblecomponents in the SI-35 feed fibre and ash.
Oxygen use for the HI treatment was 21
percent lower compared to the SI treatment
and the volume of water used to produce
1 kg of shrimp was slightly lower for the HI
treatment than the SI.
Analyses of shrimp performance based
on harvest data (see Table 4) showed no
differences in survival rate, but better mean
final weights, yields, growth, and FCR for the
shrimp fed with the HI-35 feed. This study
showed that market-size shrimp can be pro-
duced with no water exchange, and although
the cost difference between the HI and SI
feeds was significant ($1.75/kg vs. $0.99/kg), a
preliminary profitability analysis indicates thatboth feeds would be commercially viable with
the profit advantage in favor of the HI feed.
The second trial lasted 63 days and was
conducted in the two 100 m3raceway tanks
described earlier. The tanks were initially
filled with a mixture of seawater, municipal
chlorinated freshwater, and biofloc-rich water
from a previous nursery study. Whereas the
juvenile shrimp (3.14 g) in the 2011 study
Table 7. Summary of production and sales for the extrapolated commercialscale super-intensive biofloc dominated no exchange shrimp productionoperation, with 2011 trial results compared to three 2012 trials.
2011HI-35 40
m3SI-35 40
m3HI-35 100
m3
Production, kg/crop 38,320 38,960 34,840 36,120
Crops per year 4.4 5.5 5.5 5.8
Production, kg/year 168,608 214,280 191,620 209,496Production MT/year 169 214 192 209
Selling price, $/kg 7.20 7.20 7.20 7.20
Total Sales per year, $ 1,213,978 1,542,816 1,379,664 1,508,371
January-February 2014 | INTERNATIONAL AQUAFEED| 47
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VIVIndia2014April 23 - 25, 2014 | Bangalore, India
REGISTER NOWfor FREE entrance at
www.viv.netSide events
Join us at VIV India International Industry Week 2014.
The professional one-stop platform for Indias Meat, Eggs,Dairy, Pigs and Fish industries.
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8/13/2019 EXPERT TOPIC 1401- SHRIMP
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were of a Taura-Resistant strain and stocked
at 390 juveniles per m3, the shrimp (3.60 g)
used in the current study were a cross pro-duced from Taura-resistant and Fast-Growth
genetic lines, stocked at a density of 500
per m3. The shrimp were fed a HI-35 feed
using four 24-hour belt feeders for each
raceway. The tanks were maintained with no
water exchange and freshwater was added
weekly to maintain salinity and compensate
for evaporative losses. Mean water tempera-
ture, salinity, dissolved oxygen, and pH levels
were 29.6 C, 29.3 ppt, 5.5 mg/L, and 7.1
respectively. Total ammonia nitrogen and
NO2-N remained low throughout the study,
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Successful moisture
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Current challenges and opportunities
in amino acid nutrition of salmonids
VOLUME 17 I SSU E 1 2014 - J ANUARY | FEBRUARY
INCORPORAT ING
FISH FARMING TECHNOLOGY
Whisky by-products: a sustainableprotein sourcefor aquaculture
Closing the food waste loop: a new angle for insect-basedfeeds
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