STUDIES ON THE ENRICHMENT OF ARTEMIA URMIANA CYSTS FOR IMPROVING FISH FOOD VALUE
J. Hanaee, N. Agh, M. Hanaee, A. Delazar, S.D. Sarker-2005
Animal Feed Sciences and Technology 120: 107-112
Abstract:
Since no artificial feed formulation is yet available to substitute completely
for Artemia, feeding Artemia cysts to young fish larvae still remains essential
in commercial hatchery operations. The nutritional quality of commercially available
Artemia strains is relatively poor in eicosapentaenoic acid (EPA, 20:5n-3) and
docosahexaenoic acid (DHA, 22:6n-3), two major determinants of fish food value
and also the price of Artemia cysts. It is a common practice to enrich these
Artemia cysts with emulsions of marine oils. In the study reported, fatty acids
of Artemia urmiana cysts were studied by GC, both before and after their enrichment
with fish oil. Decapsulated cysts of A. urmiana were dried for 24 hr at 60°C,
fatty acids were extracted with diethyl ether, converted to the methyl esters
of fatty acid (FAME) by methanolic KOH (2N), and the esters were extracted with
n-heptane. FAMEs were injected to GC for the determination of the composition
and quantity of fatty acids. In the next stage, A. urmiana decapsulated cysts
were enriched with fish oil to increase its EPA and DHA fatty acid levels and
analysed by GC. The result demonstrated that this enrichment method brought
about an increase in the levels of EPA from 159 to 195 g/kg and DHA from 6 to
84 g/kg.
(School of Pharmacy, Tabriz University of Medical Sciences, Tabriz, IR Iran;
email of S. Sarker:
s.sarker@ulster.ac.uk)
EFFECTS OF BACTERIA ON ARTEMIA FRANCISCANA CULTURED IN DIFFERENT GNOTOBIOTIC
ENVIRONMENTS
Antonio Marques, Thi Dinh, Christos Ioakeimidis, Geert Huys, Jean Swings, Willy
Verstraete, Jean Dhont, Patrick Sorgeloos, Peter Bossier-2005
Applied and Environmental Microbiology, 71(8): 4307-4317
Abstract:
The use of probiotics is receiving considerable attention as an alternative
approach to control microbiota in aquaculture farms, especially in hatching
facilities. However, application with consistent results is hampered by insufficient
information on their modes of action. To investigate whether dead bacteria (allowing
investigation of their nutritional effect) or live bacteria (allowing evaluation
of their probiotic effect) have any beneficial effect towards Artemia franciscana
and, subsequently, if live bacteria have probiotic effects beyond the effects
observed with dead bacteria, a model system was employed using gnotobiotic Artemia
as a test organism. Nauplii were cultured in the presence of 10 bacterial strains
combined with four different major axenic live feeds (two strains of Saccharomyces
cerevisiae and two strains of Dunaliella tertiolecta) differing in their nutritional
values. In combination with poor- and medium-quality live feeds, dead bacteria
exerted a strong effect on Artemia survival but a rather weak or no effect on
individual length and constituted a maximum of only 5.9% of the total ash-free
dry weight supplied. These effects were reduced or even disappeared when medium-
to good-quality major feed sources were used, possibly due to improvements in
the health status of Artemia. Some probiotic bacteria, such as GR 8 (Cytophaga
spp.), improved (not always significantly) the performance of nauplii beyond
the effect observed with dead bacteria, independently of the feed supplied.
The present approach can be an excellent system to study the exact mode of action
of bacteria, especially if combined with challenge tests or other types of analysis
(e.g., transcriptome and proteonomic analysis).
(Laboratory of Aquaculture & Artemia Reference Center, Faculty of Bioscience
Engineering, Ghent University, Rozier 44, 9000 Ghent, Belgium; email of A. Marques:
marques_am@yahoo.com.)
USE OF COMPUTATIONAL FLUID DYNAMICS (CFD) FOR AQUACULTURE RACEWAY DESIGN TO
INCREASE SETTLING EFFECTIVENESS
Dania L. Huggins, Raul H. Piedrahita, Tom Rumsey-2005
Aquacultural Engineering 33(3): 167-180
Abstract:
A computational fluid dynamics model was used to evaluate the impact of potential
raceway design modifications on the in-raceway settling of solids. Settling
effectiveness was evaluated on the basis of the percentage of solids removed
by settling relative to the mass of solids introduced into the raceway, with
solids settling primarily in the quiescent zone (QZ).
The design modifications were applied to a simulated standard raceway (SSR).
The SSR was a rectangular concrete raceway 30.2 m long, 3.0 m wide, 0.9 m deep,
with a slope of 0.01. The raceway included a QZ of approximately 5.0 m (length),
which was separated from the rearing area by a screen. The flow rate was 0.058
m3/s.
For simulation purposes, six groups of particles were used to account for the
total suspended solids (TSS). The representative particle sizes were 692, 532,
350, 204, 61, and 35 µm, for Groups 1–6, respectively. The smallest
particles (Groups 5 and 6) are the most difficult to settle because of their
low settling velocity.
After analyzing the velocity profiles obtained from the SSR and considering
various design constraints, several raceway design alternatives were simulated.
Among the alternatives tested, six designs were chosen based on their PSR values.
The main feature in all the modifications presented is the addition of a baffle
before the QZ or at the entrance of the QZ replacing the screen. The main purpose
of adding these baffles was to increase the velocities under the baffle, which
causes an increase in the accumulation of the solids after the baffle (in the
QZ). According to the simulations, the highest PSR was obtained with the combination
of a baffle and a screen under the baffle. The overall improvement of PSR with
respect to the original system was small, with the most noticeable increases
taking place for the smaller groups of particles, from 83 to 84%, 3 to 14%,
and 1 to 5% for Groups 4–6, respectively. Further studies should include
the evaluation of some of these alternatives in real raceways and the comparison
of simulated and experimental PSR results.
(Department of Biological and Agricultural Engineering, University of California,
One Shields Avenue, Davis, CA 95616, USA ; email of D. Huggins:
dhuggins@nccn.net)
INDOOR AND OUTDOOR MASS PRODUCTION OF THE DIATOM CHAETOCEROS MUELLERI IN A MEXICAN
COMMERCIAL HATCHERY
José Antonio López-Elías, Domenico Voltolina, Fernando
Enríquez-Ocaña, Griselda Gallegos-Simental-2005
Aquacultural Engineering 33(3): 181-191
Abstract:
In tropical and subtropical countries, hatcheries may produce microalgae for
larval feeding either indoors, which is supposed to improve the quality and
reliability of production but has a higher cost, or they may use outdoor cultures
at a lower cost, but with a high seasonal variability. In this paper, we compare
the cell concentrations and the organic biomass yields and composition of indoor
and outdoor mass cultures of the diatom Chaetoceros muelleri obtained in four
seasons in a commercial hatchery of the state of Sonora, in the Mexican northwest.
Cell yields were better outdoors in spring and fall but lower in winter, whereas
in summer they were similar indoors and outdoors. Organic biomass production
was higher in spring and summer and tended to be lower, but not significantly
different, in winter. Indoors, the percentage of proteins was significantly
higher during spring, but it was lower in fall and winter. In summer, there
was no difference between outdoors and indoors. Carbohydrates were higher indoors
in summer, when lipids were higher outdoors, whereas in winter they were higher
indoors. The organic biomass production ranged from 22.5 to 45.7 g/m3/d indoors,
with a mean estimated cost of US$ 176.67 and 75.88 per kg of total biomass.
Outdoors, the mean production varied from 29.0 to 69.7 g/m3/d in winter and
spring, respectively, at a mean annual cost of US$ 50.36 per kg.
(Departamento de Investigaciones Científicas y Tecnológicas de
la Universidad de Sonora, Rosales y Niños Heroes s/n, Col. Centro, CP
83000, Hermosillo, Sonora, Mexico; email of D. Voltolino:
voltolin04@cibnor.mx)
SOLIDS REMOVAL IN A RECIRCULATING AQUACULTURE SYSTEM WHERE THE MAJORITY OF FLOW
BYPASSES THE MICROSCREEN FILTER
Robert C. Summerfelt, Chris R. Penne-2005
Aquacultural Engineering 33(3): 214-224
Abstract:
Solids capture in a sedimentation basin in the lower portion of an external
standpipe was compared with solids capture by the drum filter (DF) in a commercial
recycle aquaculture system (RAS) with dual-drain culture tanks equipped with
sidewall and bottom-center drains. The system had a unique combination of features:
sidewall drain effluent, 79% of total from the culture tank, that by-passed
the drum filter; center drain effluent of each tank discharged into an external
standpipe that functioned as a simple sedimentation basin; daily freshwater
inflow was only 1.6% of total system volume, and the waste effluent from the
culture building discharged to a septic tank with a perforated tile line that
terminated in a pond. The high-pressure backwash spray of the drum filter operated
36% of the time and contributed 40.6% of septic tank inflow. The external standpipe
contained three lengths of pipe (a triple standpipe, TSP). It was flushed manually
by pulling one of the three standpipes for 10 s once per day. At the start and
end of two 27 d intervals, samples of effluent from the DF and TSP were captured
from the septic inlet that was exposed immediately following draining of the
septic tank. Flushing the TSP (0.34 m3) contributed 59.4% of total inflow to
the septic tank and contributed solids that had accumulated in the quiescent
zone below the shortest of the three standpipes. TSP accounted for 83.2% biochemical
oxygen demand (BOD), 71.4% TN, 82.1% total phosphorus (TP), 66.1% suspended
solids (SS), 64.1% total dissolved solids (TDS) and 86.5% total suspended solids
(TSS) of the total volume of effluent water quality parameters discharging to
the septic tank. Only 21% of recirculating flow went through the microscreen
of the drum filter. The case study demonstrated the value of an inline sedimentation
basin to remove heavy solids and reduce loading of the drum filter.
(Department of Natural Resource Ecology and Management, Iowa State University,
333 Sciences 2, Ames, IA 50011-3221, USA; email of R. Summerfelt:
RSUMMERF@IASTATE.EDU)
MEASUREMENT OF DISSOLVED OZONE IN SEA WATER: A COMPARISON OF METHODS
Kevin A.H. Buchan, Debbie J. Martin-Robichaud, Tillmann J. Benfey-2005
Aquacultural Engineering 33(3): 225-231
Abstract:
Dissolved ozone levels in sea water can be quantified using various iodometric
methods, the colourmetric N,N-diethyl-p-phenylenediamine (DPD) method, or by
measuring oxidation/reduction potential (ORP). Dissolved ozone concentrations
in sea water can be expressed in mg/l of total residual oxidants (TRO), ozone
produced oxidants (OPO), residual ozone concentration (ROC) and ozone. This
study compared commonly cited methods of ozone measurement for their ability
to measure dissolved ozone and the ease with which they can be applied on-site
in an aquaculture facility. The different units for expressing dissolved ozone
concentrations were also examined. It is recommended that under non-laboratory
(i.e., hatchery) conditions, a DPD ‘total chlorine test’ be used
to measure dissolved ozone levels, and that the results be reported in TRO in
terms mg/l of Cl2.
(Department of Fisheries and Oceans, 531 Brandy Cove Road, St. Andrews, New
Brunswick, Canada E5B 2L9; email of K. Buchan:
kevin.buchan@unb.ca)
EFFECTS OF L-CARNITINE ENRICHMENT ON THE POPULATION GROWTH, EGG RATIO AND BODY
SIZE OF THE MARINE ROTIFER, BRACHIONUS ROTUNDIFORMIS
Dong Ming Zhang, Takao Yoshimatsu, Mitsuhiro Furuse-2005
Aquaculture 248 (1-4): 29 51-57
Abstract:
l-Carnitine enrichment has shown considerable influence on the population growth,
reproduction and individual growth of rotifer, Brachionus rotundiformis. Rotifers
were enriched with 8 levels of l-carnitine supplements dissolved in Nannochloropsis
oculata culture medium in a 3 ml-individual culture trial for 10 days, and 5
levels in Chlorella vulgaris culture medium in one l batch culture trial for
5 days.
In the batch culture trial, 42, 38 and 50% increase in population densities
(P < 0.05) were observed in 1, 10 and 100 mg l- 1 treatments, respectively,
whereas, the 1000 mg l- 1 treatment had a significant decrease in population
density (34–45%, P < 0.05) and markedly higher egg ratio (P < 0.05).
The 1000 mg l- 1 l-carnitine-enriched rotifers obtained significantly smaller
body size (P < 0.01), but those enriched with the other 3 levels of l-carnitine
(1, 10, 100 mg l- 1) showed larger body size. In the individual culture trial,
an increasing trend was observed in population density after 5 days and 10 days
of culture in 0.001–10 mg l- 1 treatments.
The results suggest that l-carnitine could be a positive factor to enhance reproduction
and population growth on enriched rotifers directly or/and indirectly under
the optimum concentration. The lipid metabolism in rotifers may be carnitine-dependent.
(Laboratory of Advanced Animal and Marine Bioresources, Graduate School of Bioresource
and Bioenvironmental Sciences, Kyushu University, Fukuoka 812-8581, Japan; email
of Dong Ming Zhang:
dmzhang@brs.kyushu-u.ac.jp)
LONG TERM PARTIAL REPLACEMENT OF DIETARY FISH OIL WITH RAPESEED OIL; EFFECTS
ON EGG QUALITY OF ATLANTIC SALMON SALMO SALAR
Shona Rennie, Felicity A. Huntingford, Anne-Lise Loeland, Martin Rimbach-2005
Aquaculture 248 (1-4): 135-146
Abstract:
The use of vegetable oil in broodstock diets and its effect on gamete quality
was investigated. During September 2002, 315 Atlantic salmon (2nd sea winter)
were individually tagged and divided amongst three sea cages. The fish were
fed a broodstock diet with 100% South American fish oil (at a dietary lipid
level of 27.6%) in one treatment group and with 50% (the rest replaced with
rapeseed oil) in the others. The fish were weighed and measured in November
2002, May 2003, and July 2003. Maturing fish were transferred to fresh water
in October 2003 and individual fecundity and mean egg weights were measured.
Dietary treatment did not affect egg number or egg weight. The eggs from a sub-set
of females from each treatment were fertilised using a pool of milt from three
males of the same treatment. Samples of the pre-fertilised eggs underwent fatty
acid, astaxanthin and proximate analysis. The fatty acid profiles of the eggs
and fry differed between dietary treatment, the rapeseed oil treatment producing
lower levels of DHA (22:6n-3) and EPA (20:5n-3) and higher levels of 18:1n-9,
18:2n-6 and 18:3n-3, but rates of fertilisation, eyeing, hatching, survival
to first feeding and the fry weight at first feeding did not. These results
suggest that it is possible to replace a portion of the fish oil (South American)
with rapeseed oil in a broodstock diet without compromising the early survival
and initial growth of offspring, although there could be implications for some
developmental processes not tested for in this study.
(Department of Environmental and Evolutionary Biology, University of Glasgow,
Glasgow G12 8QQ, United Kingdom; email of S. Rennie:
0007504r@student.gla.ac.uk)
EFFECTS OF DIETARY LIPID SOURCE ON SPAWNING PERFORMANCE OF NILE TILAPIA (OREOCHROMIS
NILOTICUS) BROODSTOCK REARED AT DIFFERENT WATER SALINITIES
Abdel-Fattah M. El-Sayed, Cathrine R. Mansour, Altaf A. Ezzat-2005
Aquaculture 248 (1-4): 187-196
Abstract:
The effects of dietary lipid source and water salinity on spawning performance
of Nile tilapia broodstock and growth of their larvae were studied. Three isonitrogenous
(40% crude protein), isocaloric (18.6 MJ GE/kg) diets containing three different
oil sources, soybean oil (SBO), fish oil (FO) and soybean oil/ fish oil mixture
(oil mix), were prepared. The diets were fed twice a day to satiation to duplicate
groups of broodfish (19.2 g) at a female/male ratio of 3:1, reared at three
salinities (0‰, 7‰ and 14‰), for 165 days. The size at first
maturation was not significantly affected by dietary oil source and salinity.
Spawning intervals of broodfish reared at 0‰ were not significantly affected
by dietary oil source. At 7‰ and 14‰, fish fed FO or oil mix spawned
more frequently, at shorter intervals, than those fed SBO. Dietary FO increased
the absolute fecundity and number of eggs per spawn at each salinity. At 0‰,
spawning performance and larval weight were not significantly affected by dietary
oil source. At 7‰ and 14‰, fish fed SBO needed more time for egg
hatching and yolk-sac absorption and resulted in poorer larval weight than those
fed FO or oil mix. This result revealed that Nile tilapia broodfish reared in
brackishwater require a source of dietary n-3 HUFA for optimum spawning performance,
while plant oil (SBO) may meet the requirements of broodfish reared in freshwater.
(Oceanography Department, Faculty of Science, University of Alexandria, Alexandria,
Egypt; email of A. El Sayed:
a_elsayed50@yahoo.com)
ROUTES OF IMMUNOSTIMULATION VIS-À-VIS SURVIVAL AND GROWTH OF PENAEUS
MONODON POSTLARVAE
I.S. Azad, A. Panigrahi, C. Gopal, S. Paulpandi, C. Mahima, P. Ravichandran-2005
Aquaculture 248 (1-4): 227-234
Abstract:
The present study was carried out to obtain the performance of booster doses
of immunostimulants given through different routes. Postlarvae of tiger shrimp
Penaeus monodon (PL30) were immunostimulated via immersion and oral routes using
heat-killed Vibrio anguillarum. Bath (106 CFU/ml for 1 h), bath and in-feed
(initially immersed in 106 CFU/ml for 1 h followed by two feedings with 105
CFU/feeding), and in-feed alone were used as the routes of immunostimulation.
A booster dose was given in each of the treatment groups at 20 days postpriming
(dpp).
Growth and survival were studied following priming and booster until 60 dpp.
The survival of shrimps in bath + feed treatment was significantly (P < 0.05)
higher than the bath treatment. However, initial bath priming followed by booster
through feed or bath significantly (P < 0.05) enhanced the growth and survival
of the postlarvae compared to the primed or the control. Growth was the best
with booster (bath + in-feed)-treated larvae, followed by other booster-treated
and primed groups, while it was the least in control groups. The booster dose
of immunostimulation, in general, is advantageous in inducing growth and protective
response in shrimp, and among the modes, the in-feed route of administration
may be more practical as well as productive.
(Central Institute of Brackishwater Aquaculture (CIBA), 75, Santhome High Road,
RA Puram, Chennai 600 028, India; email of A. Panigrahi:
apanigrahi2k@yahoo.com)
GENE EXPRESSION OF PEPSINOGEN DURING THE LARVAL DEVELOPMENT OF RED PORGY (PAGRUS
PAGRUS)
M.J. Darias, H.M. Murray, G. Martínez-Rodríguez, S. Cárdenas,
M. Yúfera-2005
Aquaculture 248 (1-4): 245-252
Abstract:
Ontogeny of stomach functionality during the larval development of the red porgy
was studied from morphological, physiological and molecular perspectives. The
aim of this study was to advance our understanding of the sequence of events
occurring during the transition from alkaline to acid digestion in sparids.
Gastric gland histological development was examined using haematoxylin-eosin
staining. Pepsinogen mRNA was localized using in situ hybridization on 5–7
µm sections of paraffin embedded samples. Gastric pH in the lumen of the
stomach was measured using a pH microelectrode. The first signs of gastric glands
were apparent by 19 days after hatching (dah) and were fully morphologically
developed on 26 dah approximately. Pepsinogen expression was evidenced in the
gastric glands from 30 dah onwards. The decrease in gastric pH was detected
in fed larvae above 35 dah.
(Instituto de Ciencias Marinas de Andalucía (CSIC), Apartado Oficial
E-11510, Puerto Real, Cádiz, Spain; email of M.J. Darias:
mariajose.darias@icman.csic.es)
FOOD MICROPARTICLES FOR LARVAL FISH PREPARED BY INTERNAL GELATION
M. Yúfera, C. Fernández-Díaz, E. Pascual-2005
Aquaculture 248 (1-4): 253-262
Abstract:
A novel experimental microdiet for larval fish was prepared using a modification
of the internal gelation microencapsulation procedure. In these microspheres,
a complete formulated diet is entrapped in a matrix of Ca-alginate. When compared
with our previous methodology of polymerisation of dietary protein, this procedure
has the advantage of using more environmentally friendly reagents at a lower
cost: vegetable oil and acetic acid vs. cyclohexane and trimesic acid. In addition,
it allows a more balanced formulation because no high proportion of pure protein
is required. These features represent an advantage for a potential upscaling
of this microdiet to pilot and industrial level. The present study describes
the preparation procedure and the basic characteristics of these food particles.
In addition, the microdiet was tested with fish larvae. Growth and developmental
performance of Sparus aurata larvae obtained at 15 days post hatching (dph)
fed this microdiet were similar to those previously obtained with microcapsules
prepared by crosslinking of dietary protein. Solea senegalensis larvae were
able to reach 400 µg dry weight when fed exclusively on alginate microdiet
from 7 dph up to 30 dph.
(Instituto de Ciencias Marinas de Andalucía (CSIC), Apartado Oficial
E-11510, Puerto Real, Cádiz, Spain; email of M. Yufera:
manuel.yufera@icman.csic.es)
ONTOGENETIC CHANGES IN AMINO ACID AND VITAMINS DURING EARLY LARVAL STAGES OF
STRIPED TRUMPETER (LATRIS LINEATA)
Malcolm R. Browna, Stephen C. Battaglene, David T. Morehead, Mina Brock-2005
Aquaculture 248 (1-4): 263-274
Abstract:
Changes in biochemical composition were examined during the early larval ontogeny
of striped trumpeter to 14 days post-hatch (dph). The composition of total amino
acids (wt.% of total) changed significantly from egg to first-feeding larvae
(5 dph), but during exogenous feeding with Algamac 2000-enriched rotifers for
an additional 9 days, larvae showed only minor compositional changes. The composition
of total, essential amino acids (EAAs) in first-feeding larvae was closely correlated
to the composition in rotifers, which suggested no major dietary imbalances
of EAAs.
High concentrations of free amino acids (FAAs) were found in striped trumpeter
eggs, i.e. 104 mg g- 1 dry weight (DW) and 28.5% of total amino acids. Concentrations
dropped significantly in larvae at hatch (41 mg g- 1) and further in larvae
at first-feeding (15 mg g- 1). These changes suggested a major metabolic role
of FAAs during early ontogeny of striped trumpeter.
Concentrations of ascorbic acid remained constant during exogenous feeding of
striped trumpeter (510 to 590 µg g- 1). However concentrations of a-tocopherol
decreased from 258 to 120 µg g- 1 and there was a relatively low concentration
of a-tocopherol in the feed rotifers (60 µg g- 1) indicating a-tocopherol
concentrations might be suboptimal.
The study has provided baseline information that will aid in the design of future
nutritional studies with striped trumpeter larvae to test specific hypotheses.
(Aquafin Cooperative Research Centre, CSIRO Marine Research, GPO Box 1538, Hobart,
Tasmania 7001, Australia; email of Malcolm Brown:
Malcolm.Brown@csiro.au)
DIETARY 22:6N-3 ALTERS GUT AND LIVER STRUCTURE AND BEHAVIOUR IN LARVAL STRIPED
TRUMPETER (LATRIS LINEATA)
M.P. Bransden, J.M. Cobcroft, S.C. Battaglene, D.T. Morehead, G.A. Dunstan,
P.D. Nichols, S. Kolkovski-2005
Aquaculture 248 (1-4): 275-285
Abstract:
The effect of dietary 22:6n-3 on larval striped trumpeter growth, morphology,
feed intake and behaviour was investigated. A dose–response technique
was used. Seven experimental emulsions were formulated with increasing concentrations
of 20:5n-3 and 22:6n-3 and used to enrich rotifers (Brachionus plicatilis).
Enriched rotifer 22:6n-3 concentrations ranged from approximately 2 to 16 mg/g
dry matter (DM). Enriched rotifers were fed to striped trumpeter larvae from
5 to 18 days post-hatch (dph). No relationship was identified between larval
growth or survival and dietary 22:6n-3, nor was there any significant relationship
between larval response to salinity and temperature challenges to dietary 22:6n-3.
Larvae fed low dietary 22:6n-3 displayed erratic swimming behaviour, suggesting
inferior quality larvae compared with those fed higher dietary 22:6n-3. A significant
inverse relationship between the syndrome, ‘grey gut’, and dietary
22:6n-3 was found. Histologically, grey gut was associated with extensive vacuolation
of enterocytes, probably lipid droplets, indicating a dietary imbalance of fatty
acid resulting in abnormal lipid assimilation, transport and subsequent deposition.
Similarly, hepatocytes of larvae fed low 22:6n-3 were also highly vacuolated
in comparison with the compact liver tissue of larvae fed high dietary 22:6n-3.
Data suggests that striped trumpeter larvae benefit from the inclusion of dietary
22:6n-3, and failure to provide it above a minimum threshold can result in behavioural
differences and problems in lipid assimilation and transport. Our study demonstrates
that larval nutrient requirement studies can benefit from the use of dose–response
techniques commonly used in larger fish.
(Marine Research Laboratories, Tasmanian Aquaculture and Fisheries Institute
and Aquafin Cooperative Research Centre, University of Tasmania, Private Bag
49, Hobart, Tasmania, 7001, Australia; email of Matthew Bransden:
Matthew.Bransden@utas.edu.au)
