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Red snapper is the most important economically valuable
aquaculture species in Taiwan. Studies on the nutritional
requirements of thisspecies are still lacking. The experiment
was conducted to determin a suitable dietary composition for
red snapper reared in seawater by feeding with various levels
of protein, lipid and n-3 HUFA. The results are as follows: 1.
At the same dietary lipid levels, the weight gain and feed
efficiency were higher in fish fed diets 45% CP than those fed
diets 40% CP. 2. As the dietary lipid increased,the
accumulation of lipid in muscle and liver increased in fish fed
diets 40% and 45% CP. At the same dietary lipid levels, fish
fed diets 45% CP accumulated less lipid in liver than those fed
diets 40% CP. increase in dietary lipid levels, the n-3 HUFA
contents in muscle and liver also increased. 3. When the n-3
HUFA content in diets were adjusted by beef tallow inthe range
from 0.9% to 2.2%, the lowest weight gain and feed efficiency
were demostrated in fish fed diet 0.9% n-3 HUFA. 4. Fish fed
diet 1.4% n-3 HUFA accumulated the most lipid in muscle and
liver, those fed diet 0.9% n-3 HUFA the least. 5. The hightest
Σn-3 ratio in muscle was demostrated in fish fed diet 2.2% n-3
HUFA. The highest Σn-3 ratio in liver was also found in fish
fed 2.2% n-3 HUFA, and the lowest in fish fed diet 1.2% n-3
HUFA. These results indicated that the optimal dietary protein
and lipid levelsfor red snapper reared in seawater are 40─45%
and 9─12%.The n-3 HUFA contents in diets should be over 1.6%
when dietary protein and levels are fixed at 45% and 12%.
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