The effects of dietary Docosahexaenocic acid (22:6n-3) and Arachidonic acid (20:4n-6) on growth, survival and stress resistance in black sea bass (Centropristis striata) larvae
- UNCW Author/Contributor (non-UNCW co-authors, if there are any, appear on document)
- Troy Rezek (Creator)
- Institution
- The University of North Carolina Wilmington (UNCW )
- Web Site: http://library.uncw.edu/
- Advisor
- Wade Watanabe
Abstract: The black sea bass is an important commercial and recreational fishery species on
the U.S. Atlantic coast. Decreasing commercial catch and high market value make the
black sea bass a promising candidate for aquaculture. Knowledge of the nutritional
requirements of the larval stages is fundamental to achieve large scale production of
fingerlings or growout farms. Essential fatty acids, especially 22:6n-3 (Docosahexaenoic
acid, DHA), 20:5n-3 (Eicosapentaenoic acid, EPA) and 20:4n-6 Arachidonic acid (ArA)
are known to have important affects on larval growth and survival in marine finfish.
Little or no published information is available on the nutritional requirements of larval
black sea bass. The objectives of this study were to determine the effects of dietary DHA
to ArA ratio on survival, growth, and stress resistance of black sea bass larvae raised
from first feeding to metamorphic stages.
Yolksac larvae (day 0 post-hatching = d0ph) were stocked into 15-L aquaria (44
larvae/L) under 34 ppt and 20°C. Larvae were fed enriched rotifers and Artemia nauplii
containing two levels of DHA (0 and 10%) in conjunction with three levels of ARA (0, 3
and 6%) in a 2 x 3 factorial design. Five replicate aquaria were assigned to each
treatment. Larvae were fed enriched rotifers (Brachionus sp.) from d2ph to d17ph, and
Artemia from d18 to d24ph, when all larvae had reached the metamorphic stage. Larvae
were sampled weekly to monitor growth as (notochord length (NL), dry weight, wet
weight) and survival. On d24ph, a hypersaline (60 ppt) stress test (median survival time
at 50% survival) was administered. Rotifers, Artemia and samples of larvae were
collected from each treatment to determine fatty acid composition.On d24ph, larvae fed treatment 10:6 (DHA:ARA) showed significantly (P < 0.05)
higher survival (16.7%), than larvae fed 0:0 (DHA:ARA) (7.0%). NL and dry weight
were also significantly (P < 0.05) greater at the 10:6 (DHA:ARA) treatment level (8.65
mm, 2.14 mg) than in the 0:0 (DHA:ARA) (7.7 mm, 1.65 mg) treatment. During
hypersaline challenge, no significant differences (P > 0.05) were shown between larvae
fed 10% DHA (25.6 min) and larvae fed 0% DHA (18.2 min.). On d24ph, levels of ArA
in black sea bass larvae were higher than levels provided in their diets, while DHA levels
were higher in larvae fed 10% DHA than in larvae fed 0% DHA. EPA (20:5n-3) levels
were also higher in the larvae fed 10% DHA than in larvae fed 0% DHA. These results
suggest conversion of EPA to DHA by black sea bass larvae, but at rates insufficient to
produce optimum growth and survival.
To summarize, black sea bass larvae fed prey containing 10% DHA showed better
growth and survival than those fed 0% DHA. Increased ARA within the range of 0-6%
improved growth and survival from the first feeding through metamorphic stages.
The effects of dietary Docosahexaenocic acid (22:6n-3) and Arachidonic acid (20:4n-6) on growth, survival and stress resistance in black sea bass (Centropristis striata) larvae
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Created on 1/1/2009
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Additional Information
- Publication
- Thesis
- A Thesis Submitted to the University of North Carolina Wilmington in Partial Fulfillment Of the Requirements for the Degree of Masters of Science
- Language: English
- Date: 2009
- Keywords
- Black sea bass--United States--Atlantic Coast--Growth, Black sea bass--Larvae--United States--Atlantic Coast, Black sea bass--Nutrition--Research, Centropristis--research, Proteins in animal nutrition, Dietary Supplements