• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.6
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• pp.761-768
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• 2013

We conducted two feeding trials to investigate the optimal feeding frequency of juvenile Korean rockfish Sebastes schlegeli fed a commercial diet of expanded pellets containing 47.2% crude protein, 9.2% crude lipid, and 14.5% ash at two different water temperatures. In the first experiment, triplicate groups of 20 fish with an average weight of 2 g were fed an equal amount of diet (5.97% based on body weight) at one of six feeding frequencies (2, 3, 4, 5, 7, or 9 meals/day) for four weeks at $17.5^{\circ}C$. After four weeks, we measured weight gain (WG), specific growth rate (SGR), feeding efficiency (FE), and protein efficiency ratio (PER). Fish fed diet five meals/day grew significantly better than those fed nine meals/day. The second experiment used identical experimental conditions and feeding regions, except the food ration was slightly less (5.92% based on body weight) and the water temperature was increased to $20^{\circ}C$. After four weeks, we again measured WG, SGR, FE and PER. Fish fed seven meals/day grew significantly faster than those fed 2, 3, 4, or 9 meals/day. Whole-body protein levels in fish fed three meals/day was higher than those fed four meals/day in $17.5^{\circ}C$ water, but whole-body lipids in the fish fed four meals/day was higher than those fed two meals/day in $20^{\circ}C$ water. A second-order polynomial analysis based on WG suggested the optimal feeding frequency for juvenile Korean rockfish was five meals/day at $17.5^{\circ}C$ and six meals/day at $20^{\circ}C$, indicating that fish reared in higher water temperature require higher feeding frequencies.

• Journal of the Korean Society of Food Science and Nutrition
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• v.12 no.4
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• pp.395-400
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• 1983

The experiment was conducted to study the effect of protein level on weight gain, feed consumption and the efficiencies of feed, energy and protein when the broiler chick was fed the diet of different protein level with the iso-calorie content. The energy and protein level of the basal ration was 3200 kcal and 22.85% for starter period and 3265 Kcal and 18.58% for finisher period, respectively. In order to increase the protein level of the experimental diet, the basal diet was substituted by fish meal by the ratio of 3, 6, 9, and 12%. The male Abor Acre broiler chicks were employed for 8 weeks and the result obtained were as follows. 1. The weekly body weight gain was significantly greater for Diet C than for Diet A and E in the starter period and greater for Diet A than for Diet E in the finisher period (P<0.05). 2. In stater period the feed intake was not affected by the protein level but in finisher period the feed intake for Diet C, D, and E was significantly reduced compared with Diet A. 3. As for feed conversion ratio, Diet C of 1.43 was improved significantly compared with Diet A of 1.58(P<0.05). 4. As the protein level of diet increased, the energy efficiency ratio increased and however, the protein efficiency ratio decreased in starter and finisher period. In conclusion the best performance of broiler is thought to be realized when the protein and energy level was 23% and 3200 Kcal for starter period and 20% and 3250 Kcal for finisher period, respectively.