• Journal of Aquaculture
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• v.13 no.3
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• pp.207-213
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• 2000

Five diets, containing different levels (0.3-1.5%) of n-3 highly unsaturated fatty acids (n-3HUFA) adjusted by adding different ratio of squid liver oil and soybean oil to 8% lipid, were fed to the rockfish (130 g) for 8 weeks. Mean weight gain and feed efficiency were lowest in the fish fed the diet containing 0.3% n-3HUFA. These values improved with increasing squid liver oil, and showed linear relation up to 0.6% n-3HUFA, Using the brocken line model, the dietary n-3HUFA requirement was estimated as about 0.9 % for optimal weight gain of the fish. Crude lipid levels of the liver in 0.3-0.6%) n-3HUFA diets were significantly higher than in the 1.5% n-3HUFA diet (P<0.05). Fatty acid composition of polar lipid in the liver were directly affected by dietary lipid sources. The level of n-3HUFA of polar lipid in the liver increased with dietary n-3HUFA levels, although 18:2n-6 content decreased. Hence the n-3HUFA requirement of a growing rockfish is 0.6-0.9% of diet.

• Journal of Aquaculture
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• v.9 no.4
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• pp.385-394
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• 1996

A 15-week feeding experiment was conducted to determine the effects of feeding frequency from 2 different formulated diets on growth, feed efficiency and body composition in juvenile Korean rockfish (Sebastes schlegeli). Duplicate groups of the 30 fish averaging 25 g were fed the control diet containing $58\%$ fish meal and the experimental diet containing $40\%$ fish meal, $10\%$ meat meal, $3\%$ corn gluten meal, $3\%$ soybean meal, and $3\%$ blood meal as protein sources at different feeding frequencies of 2 times daily, once a day in the morning or afternoon, once in 2 days, or given no food. Growth and feed efficiency of the fish were affected by diets (P<0.05), whereas these values were unaffected by feeding frequencies (P>0.05). Feed intake (${\%}$ of body wt.) of the fish fed once in 2 days was lower than that of the fish fed 2 times daily and once a day (P<0.05), Moisture, protein, lipid and ash contents of liver and muscle were not influenced by different diets and feeding frequencies (P>0.05). These results indicate that once a day or once in 2 days feeding regimen must be more effective and economical than that of 2 times daily for juvenile Korean rorkfish.