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Effect
of arachidonic acid levels in broodstock diet on larval and egg
quality of Japanese flounder Paralichthys olivaceus
Authors:
H. Furuita(a), T. Yamamoto(a), T. Shima(a), N. Suzuki(a) and T.
Takeuchi(b)
(a)
Inland Station, National Research Institute of Aquaculture, Fisheries
Research Agency, Tamaki, Mie 519-0423, Japan
(b) Department of Aquatic Bioscience, Tokyo University of Fisheries,
Minato, Tokyo 108-8477, Japan
Source:
Aquaculture, vol. 220:725-735
Abstract
This study investigated the effect of dietary arachidonic acid
(AA) in broodstock of Japanese flounder on subsequent egg and
larval quality. Diets with similar proximate composition and n-3
HUFA level, but with different AA levels (0.1%, 0.6% and 1.2%
of diet), were fed to the broodstock from 3 months before and
during the spawning season. Spawning was observed from March to
May. Total egg production over the spawning season was highest
in fish fed the 0.6% AA diet and lowest in fish fed the 1.2% AA
diet. All parameters measured as egg quality (percentage of buoyant
eggs, hatching rate, larval survival and normality of larvae.)
were highest in fish fed the 0.6% AA diet. AA content in eggs
proportionally increased with the dietary AA level. EPA content
of polar lipids of eggs had a negative correlation with the AA
level in diets whereas the DHA content was independent of dietary
AA. The results of this study indicate that a supplement of AA
at 0.6 g/100 g diet improved the reproductive performance of Japanese
flounder, but a higher level of AA (1.2 g/100 g diet) negatively
affected both egg and larval quality due to a potential inhibitory
effect on EPA bioconversion.
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Effect
of Astaxanthin on Growth and Survival of Penaeus monodon Larvae
Authors:
Darachai, J; Piyatiratitivorakul, S; Menasveta, P
Source:
Proceedings of the 37th Kasetsart University Annual Conference.,
Text & Journal Publication Co., May 1999, pp. 36-41
Abstract:
The aim of the present study is to compare the efficiency of algal,
synthetic and other natural astaxanthin on growth and survival of
Penaeus monodon larvae. Four diets: algal astaxanthin-added diet
(AAD, astaxanthin was collected from Haematococcus pluvialis NIES144),
synthetic astaxanthin-added diet (SAD), non-astaxanthin supplemented
diet (CD) and natural food (NF) were fed to shrimp larvae of different
stages. The larvae fed with AAD showed the highest survival rate
and had the same growth rate as the group fed NF. Both larvae fed
with AAD and NF showed significant higher growth rate than the groups
fed SAD and CD (P<0.05).
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Effect
of Astaxanthin on Stress Resistance of Penaeus monodon Larvae
Author:
Darachai, J; Piyatiratitivorakul, S; Menasveta, P
Source:
Proceedings of the 37th Kasetsart University Annual Conference.,
Text & Journal Publication Co., May 1999, pp. 240-245
Abstract:
The aim of the present study is to compare the efficiency of algal,
synthetic and other natural astaxanthin on stress resistance of
Penaeus monodon larvae. Four diets: algal astaxanthin-added diet
(AAD, astaxanthin was collected from Haematococcus pluvialis NIES144),
synthetic astaxanthin-added diet (SAD), non-astaxanthin supplemented
diet (CD) and natural food (NF) were fed to shrimp larvae of different
stages. The test of changing salinity was done when the larvae came
to postlarvae 15. The group fed with AAD could tolerate in low salinity
stress better than the group fed with SAD, NF and CD. Carotenoids
contents in shrimp larvae fed with NF, AAD, SAD and CD were 179.54
plus or minus 0.65, 122.57 plus or minus 5.62, 109.67 plus or minus
0.47 and 97.33 plus or minus 3.42 ppm, respectively.
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Modulation
of Arachidonate and Docosahexaenoate in (Morone chrysops) Larval
Tissues and the Effect on Growth and Survival
Authors:
Harel M1; Lund E; Gavasso S; Herbert R; Place AR
1Center
of Marine Biotechnology, University of Maryland, Baltimore, Maryland
21202, USA. harel@umbi.umd.edu
Source:
Lipids, Vol. 35, No. 11 (Nov. 2000), 1269-80
Abstract
The
extent to which extreme dietary levels of arachidonate (AA) and/or
docosahexaenoate (DHA) modulate lipid composition in the body tissues
and consequently affect growth and survival in freshwater Morone
larvae species was examined. White bass, M. chrysops, larvae (day
24-46) were fed Artemia nauplii enriched with algal oils containing
varying proportions of AA and DHA (from 0 to over 20% the total
fatty acids). Growth was significantly reduced (P< 0.05) in larvae
fed a DHA-deficient Artemia diet. Increases in dietary levels of
AA also were associated with a significant growth reduction. However,
the inhibitory effect of AA on larvae growth could be suppressed
by the dietary addition of DHA (at a level of 21.6% of the total
fatty acids in enrichment lipids). Larval brain + eyes tissue accumulated
over 10 times more DHA than AA in its structural lipids (phosphatidylcholine,
phosphatidylethanolamine) at any dietary ratio. In contrast, DHA
accumulation, as compared to AA, in gill lipids declined considerably
at higher than 10:1 DHA/AA tissue ratios. DHA and eicosapentaenoic
acid (EPA) contents in brain + eyes tissue were most sensitive to
competition from dietary AA, being displaced from the tissue at
rates of 0.36 ± 0.07 mg DHA and 0.46 ± 0.11 mg EPA
per mg increase in tissue AA, and 0.55 ± 0.14 mg AA per mg
increase in tissue DHA. On the other hand, AA and EPA levels in
gill tissue were most sensitive to dietary changes in DHA levels;
AA was displaced at rates of 0.37 ± 0.11 mg, whereas EPA
increased at rates of 0.68 ± 0.28 mg per mg increase in tissue
DHA. Results suggest that balanced dietary DHA/AA ratios (that allow
DHA/AA ratios of 2.5:1 in brain + eyes tissue) promote a high larval
growth rate, which also correlates with maximal regulatory response
in tissue essential fatty acids.
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Docosahexaenoic
acid Is Superior to Eicosapentaenoic acid as the Essential Fatty Acid
for Growth of Grouper, Epinephelus malabaricus
Authors:
Feng-Cheng Wu2,3, Yun-Yuan Ting3 and Houng-Yung Chen2,4
2 Institute
of Marine Biology, National Sun Yat-sen University, Kaohsiung 804
Taiwan, Republic of China and
3 Tainan Branch, Taiwan Fisheries Research Institute, Tainan County
724 Taiwan, Republic of China
Source:
Journal of Nutrition, 132, 72-79, 2002.
Abstract
Juvenile
grouper (Epinephelus malabaricus) were fed seven experimental diets,
one control diet and one reference diet for 12 wk to determine the
dietary requirement of grouper for docosahexaenoic (DHA) and eicosapentaenoic
(EPA) acids. Each of the seven diets contained 1 g/100 g DHA and
EPA in various combinations and 9 g/100 g tristearin. The control
diet contained 1 g/100 g trilinolenin and trilinolein (3:1, wt/wt),
and no supplemental EPA or DHA. The reference diet contained only
natural oils from a mixture of cod liver oil, linseed oil and safflower
oil at a ratio of 2:1:1 (wt/wt/wt). Significant differences (P <
0.05) in growth were observed among the dietary treatments but not
in survival rate or relative liver weight. Only the diet with the
highest DHA/EPA ratio (3:1) promoted significantly greater growth
than the control diet. Purified EPA and DHA did not perform better
in promoting growth than did the impure EPA and DHA oils. Enhanced
growth was observed when the dietary DHA/EPA ratio was greater than
1, indicating that DHA was superior to EPA in promoting fish growth.
Neutral lipid (NL) was the predominant lipid fraction (>70%)
in both liver and muscle. Tissue NL/polar lipid did not differ among
groups except the reference diet group that had a higher ratio (P
< 0.05). DHA and EPA levels in the grouper tissues, especially
muscle, were highly reflective of dietary levels of DHA and EPA,
indicating that direct incorporation was likely. In addition, the
20:1(n-9), concentration in NL fractions seems to be an appropriate
indicator of dietary essential fatty acid deficiency in grouper.
1 This
research was in part supported by Grant 88-AST-1.4-FID-02.6 from
the Council of Agriculture, Taiwan, Republic of China
4 To whom correspondence should be addressed. Email: hychen@mail.nsysu.edu.tw
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Improved
Enrichment of Artemia Using a Novel Algal Derived Material
Ingrid
Lein1, Y. Barr1, Moti Harel3, P. Behrens3, A. Place2, G.M. Berge1
1AKVAFORSK
(Institute of Aquaculture Research), N-6600 Sunndalsora, Norway
2Center of Marine Biotechnology, University of Maryland, Biotechnology
Institute,
701 E. Pratt St., Baltimore, MD 21202 USA
3Martek Biosciences Corporation, 6480 Dobbin Road, Columbia, MD
21045 USA
Source:
"Cultivation of Cold Water Species: Production, Technology and Diversification,"
Aquaculture Trondheim '97, Trondheim, Norway
Introduction
Enrichment
techniques for improving the nutritional value of live food is widely
used in marine fish hatcheries. Recent studies indicate the importance
of the essential fatty acids docosahexaenoic acid (DHA) and eicosapentaenoic
acid (EPA), and also the DHA/EPA-ratio, for normal pigmentation,
metamorphosis, and stress tolerance in marine fishes. Larvae of
cold water species, e.g. Atlantic halibut (Hippoglossus hippoglossus
L.) contain high levels of DHA (25-30% of total lipids), and also
have a high DHA/EPA-ratio (about 2.5) at onset of exogenous feeding,
indicating that these larvae need high amounts of DHA and DHA/EPA
ratios in their feed. However, such high levels in feeds have not
been achieved when using traditional enrichment products based on
emulsified fish oils. The present work was carried out in order
to test enrichment products which facilitate high contents of DHA
and DHA/EPA-ratios in Artemia.
Material and methods
A novel
algal derived material was used as experimental enrichment material.
This material is high in DHA (>48% with no EPA), and constitutes
spray dried phospholipid extract of algal biomasss. The effect of
dosage and duration of the enrichment was tested with brine shrimp
Artemia containing 1% DHA of the total fatty acids (premium grade,
Sanders Brine Shrimp Co., Ogden, Utah, USA). In the first set of
experiments, 2-3 portions of 0.1, 0.2 or 0.3 1-1 were added to artificial
sea water (20ppt, 28ºC) to instar-II-stage Artemia nauplii
(200,0001-1) after 8, 12 or 16h. Survival, growth, lipid content,
lipid composition and fatty acid profiles were measured during 24h
enrichment period.
In
the second set of experiments, comparisons with four other commercial
enrichment products which are all used to gain high DHA-contents
and high DHA/EPA-ratios in the live food were carried out with instar-II
Artemia and 60h old Artemia. Duration of enrichment was 16h with
the DHA phospholipid, and 24h with the four commercial products,
in accordance to producers' recommendations. Artemia survival, lipid
content, lipid composition and fatty acid profile were measured
during the enrichment period. All experimental treatments were carried
out in triplicates.
Results
In
the first set of the experiments, Artemia survival after 16h enrichment
was over 80% at the highest portion of 0.3g/liter, with a significant
drop to 50% after 24h. Size of Artemia nauplii increased from 620µm
in length at instar-II up to a maximal size of 900µm after
16h. Lipid content increased from 16.3% DW at instar-II to 23.8
and 25.3% DW at 0.2 and 0.3g/liter portions (fed at 0 and 8h), respectively
after 24h enrichment. Triglycerids/phospholipids ratio increased
only at the higher portion of 0.3g/liter from an initial ratio of
3.18 at instar-II to 3.83 after 16h enrichment. Maximal DHA content
of 17.2% of the total fatty acids was achieved after 16h enrichment
at the highest portion of 0.3g/liter, whereas EPA content slightly
increased from an initial content of 5% to 6.2%. In the second set
of experiments, the survival of Artemia enriched with DHA phospholipid
(0.3g/liter fed at 0 and 12h) and with the four commercial diets
was not significantly different (75-100%) at the end of the enrichment
period. On the other hand, the DHA phospholipid material resulted
in a high content of DHA and a DHA/EPA-ratio significantly higher
than in any of the commercial diets (Table I). There was a large
variation in total lipid content of the Artemia fed on the different
diets (ranging from 16.0-34.3%, Table I).
Table
I. Relative content (% of fatty acids) of DHA and EPA DHA/EPA ratio
and total lipid in starved Artemia nauplii and 16h enrichment with
the DHA-rich phospholipid diet, or for 24 hours with four commercial
enrichment products.
|
Enrichment
Diet
|
DHA
|
EPA
|
DHA/EPA
|
Total
Lipids
|
| Starved
Nauplii |
1.1
|
3.7
|
0.3
|
9.9
|
| DHA-Rich
Phospholipid |
17.1
|
4.0
|
3.8
|
28.5
|
| Commercial
Diet No: |
|
|
|
|
|
1
|
11.5
|
9.1
|
1.3
|
34.3
|
|
2
|
7.8
|
8.0
|
1.0
|
16.0
|
|
3
|
10.7
|
15.0
|
0.7
|
29.3
|
|
4
|
8.8
|
8.1
|
1.1
|
24.8
|
Conclusion
The
results from the present study show that the DHA spray dried phospholipid
diet resulted in the highest DHA content and the highest DHA/EPA-ratio
reported so far. The DHA content of the enriched Artemia was 17.2%
of the total fatty acids, which is almost similar top that present
in halibut larvae at onset of exogenous feeding (20-25%). Maximal
DHA/EPA-ratio in Artemia enriched with DHA phospholipid diet, in
both sets of experiments, was ranging from 2.78-3.8, which is even
higher than that found in halibut larvae (2.5). These results provides
the possibility to test the hypothesis that cold water species and
flatfishes need high levels of DHA and high DHA/EPA-ratios in the
feed. Artemia enriched with the DHA-rich phospholipid extract are
currently being tested in first feeding of halibut larvae.
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