Sung-Sam Kim

Effects of Dietary Supplementation of Spirulina and Quercetin on Growth, Innate Immune Responses, Disease Resistance Against Edwardsiella tarda, and Dietary Antioxidant Capacity in the Juvenile Olive Flounder Paralichthys olivaceus

A 10-week feeding trial was conducted to examine the effects of dietary spirulina and quercetin on growth, innate immunity, disease resistance and dietary antioxidant capacity in the juvenile olive flounder. Triplicate groups of fish (initial body weight, 2.9 ± 0.01 g) were fed one of isonitrogenous (48% crude protein) and isocaloric (17.4 MJ/kg DM) experimental diets containing 0% spirulina (as a control), 3.4% spirulina, or 6.8% spirulina with or without supplementation of 0.5% quercetin (designated as CON, SP3.4, SP6.8, and SP6.8 + Q, respectively) at a rate of 3% body mass twice daily. Higher dietary antioxidant capacity was found with spirulina supplementation, and the highest value (P < 0.05) was obtained with SP6.8 + Q diet. At the end of the feeding trial, no significant effects were observed on growth performance, body composition and disease resistance against Edwardsiella tarda. Lysozyme activity was significantly increased by spirulina supplementation (P < 0.05), and the highest value was observed in the group fed SP6.8 + Q diet. Also, significantly higher respiratory burst activity (P < 0.05) was found in SP3.4 group. According to the results of this study, dietary supplementation of 3.4% spirulina may enhance innate immunity of olive flounder.

Effects of Dietary Supplementation of Fermented Garlic Powder on Immune Responses, Blood Components, and Disease Resistance against Principal Fish Disease of Juvenile Olive Flounder, Paralichthys olivaceus in Low Temperature Season

We report non-specific immune responses and disease resistance against Vibrio anguillarum, Streptococcus iniae and Edwardsiella tarda by dietary supplementation of fermented garlic powder (FGP) in olive flounder for the first time. Four isonitrogenous (45% crude protein) and isocaloric (17.1 MJ/kg) diets were formulated to have 0%, 0.5%, 1% and 2% of the FGP (G-0, G-0.5, G-1 and G-2). The experimental diets were fed to juvenile olive flounder averaging 23.4 g in triplicate groups (90 fish/group) in a flow-through system. After a five-week feeding trial, healthy fish with similar sizes from each tank were selected and injected with 1 ml of three bacteria each to evaluate disease resistance of the fish. During the 5-week feeding trial, the weight gain, specific growth rate, feed conversion ratio, protein efficiency ratio, and survival of the fish were not significantly affected by the experimental diets. However, feed intake was significantly lower (P<0.05) in the fish fed the G-2 diet compared with the control group. Hemoglobin, myeloperoxidase activity, cholesterol and HDL-cholesterol were not different between the dietary groups. However, hematocrit, nitroblue tetrazolium (NBT) activity, and lysozyme activity were increased (P<0.05) with an increment of dietary FGP. Plasma triglyceride of the fish fed the G-0.5 diet was significantly lower than that of fish fed the control diet. The cumulative mortality was lower in the fish fed diets containing FGP compared with the control group in the challenge test except for the bacteria Edwardsiella tarda. The results in this study indicate that dietary supplementation of FGP can enhance the non-specific immune responses and disease resistance of olive flounder against V. anguillarum and S. iniae. (Key words : Olive flounder, Fermented garlic powder, Non-specific immune response, Challenge test)

Optimum Feeding Rates in Juvenile Olive Flounder Paralichthys olivaceus Fed Practical Expanded Pellet at Low and High Water Temperatures

Two feeding trials were conducted to investigate the optimum feeding rates in juvenile olive founder Paralichthys olivaceus fed practical expanded pellet(EP) containing 58.1% crude protein, 10.7% crude lipid, and 10.8% ash at low and high water temperatures. In the first experiment, triplicate groups of 15 fish with average weight of 7.7 g were fed at one of seven feeding rates(0, 1, 1.5, 2, 2.25, or 2.5% of body weight/day or to satiation) for 4 weeks at low water temperature. In the second experiment, quadruplicate groups of 20 fish with average weight of 5.5 g were fed at one of eight feeding rates(0, 3, 3.5, 4, 4.25, 4.5, or 4.75% of body weight/day or to satiation) for 4 weeks at high water temperature. Based on growth performance, we estimated that the optimum feeding rates for juvenile olive flounder were 1.97-2.51% and 4.82-6.36% of body weight/day at low and high water temperatures, respectively. Key words; Olive flounder, Optimum feeding rates, Low temperature, High temperature, Extruded pellet

Comparison of Growth Performance and Whole-body Amino Acid Composition in Red Seabream (Pagrus major) Fed Free or Dipeptide Form of Phenylalanine

This study was conducted to evaluate the efficacy of the dipeptide form of phenylalanine as a new source of amino acid in terms of growth performance and whole-body amino acid composition in comparison to the free form for red seabream (Pagrus major). Fish (1.46±0.001 g) were fed four isonitrogenous and isocaloric experimental diets containing 0.7 or 1.4% phenylalanine either in free or dipeptide form. A feeding trial was carried out in three replicates and the fish were fed to apparent satiation for six weeks. At the end of the feeding trial, feed intake of fish was influenced by both phenylalanine form and level and significantly higher values were obtained at an inclusion level of 0.7% and by the use of dipeptide form. However, the other growth parameters did not significantly differ among treatments. Whole-body amino acid compositions revealed no significant changes in concentrations of both essential and non-essential amino acids regardless of the increase in phenylalanine levels or the use of its different forms. The finding in this study indicates that juvenile red seabream can utilize dipeptide phenylalanine as efficiently as free form without any undesirable effects on growth performance or whole-body amino acid composition.

Comparison of Extruded and Moist Pellets for Growth Performance, Water Quality and Histology of Olive Flounder Paralichthys olivaceus in Jeju Fish Farm

Abstract Two types of diets, extruded pellet (EP) and raw-fish-based moist pellet (MP) were fed to compare growth, water quality and histology of olive flounder, Paralichthys olivaceus in Jeju fish farm. Two groups of 7000 fish per each tank (initial mean weight 51 g) were fed one of two diets for 7 months. At the end of the feeding trial, significant differences were found in weight gain and feed utilization. Dissolved oxygen (DO) level of the MP tank was decreased from 7.98 to 6.89 after feeding. There were no significant differences in hematocrit, hemoglobin, alanine aminotransferase and aspartate aminotransferase of fish fed the two diets. Whole body protein content of fish fed the EP was significantly higher than that of fish fed the MP. While the feeding rate by month indicated numerically decreased, fish fed the MP had higher feed intake than that of fish fed the EP. Histological examination of hepatopancreas, kidney, and anterior intestine of fish fed the EP did not show any negative effects compared to those of fish fed the MP. This study revealed that EP could substitute for MP in terms of growth performance, blood parameters, water quality and histology of olive flounder.Key words : Olive flounder, Extruded pellet, Moist pellet, Dissolved oxygen, HistologyCorresponding author : 064-754-3423, kjlee@jejunu.ac.kr* 2014 .

Effect of Dietary Supplementation with Alga (Hizikia fusiformis and Ecklonia cava) on the Non-specific Immune Responses of Parrot Fish Oplegnathus fasciatus

Two feeding trials were conducted to determine the effects of dietary supplementation with Hizikia fusiformis or Ecklonia cava on the non-specifi c immune responses of parrot fi sh Oplegnathus fasciatus. Fish were fed experimental diets to which H. fusiformis or E. cava powder were added to fi nal concentrations of 0, 2, 4 and 6%, respectively. After feeding for two weeks, phagocytic activity was signifi cantly higher in fi sh fed diets containing H. fusiformis, but not E. cava, than in fi sh fed the basal diet. Lysozyme activity was signifi cantly increased in the fi sh fed diets containing 6% H. fusiformis and E. cava. Myeloperoxidase activity was also signifi cantly higher in fi sh fed diets containing 2 and 4% H. fusiformis, as compared to the basal diet, but not in those fi sh fed E. cava. These two studies indicate that dietary supplementation with H. fusiformis or E. cava could enhance the innate immune responses of parrot fi sh during their growth stage.

Optimum Feeding Rate for Sub-adult Olive Flounder (384 g) Paralichthys olivaceus Fed Practical Extruded Pellets at Optimum Water Temperatures (20-24.5℃)

세계 양식선진국은 환경친화적 배합사료를 사용하여 지속가 능한 양식업을 육성하고 양식시스템을 자동화하는 등 경쟁력을 강화하고 있다. 배합사료의 사용은 자동공급기를 통해 사료를 공급할 수 있을 뿐 아니라 체계적인 사육관리를 통해 양식방법 을 효율화 시킬 수 있다. 우리나라도 안전한 양식수산물 공급, 수산자원 남획 및 어장환경오염 방지 등 지속가능한 양식업 육 성을 위하여 배합사료 사용 확대가 필요한 시점이다(Kim et al., 2014). 최근 제주, 여수, 신안, 거제, 울진 및 영덕을 배합사료 시 범지역으로 선정하여 다양한 해산어류를 생사료를 사용하지 않 고 배합사료를 사용하여 양식하고 있다. 하지만 각 양식어종에 대한 배합사료 공급프로그램이 개발되지 않아 실제 양식현장 에서는 대부분 만복공급을 실시하고 있는 실정이다. 배합사료 의 만복공급은 사료의 허실로 인한 수질오염 및 생산단가 상승 을 초래하며, 소화 및 대사 장애 등의 문제점이 발생할 수 있다 적수온(20-24.5°C)에서 사육한 미성어기(384 g) 넙치 (Paralichthys olivaceus)의 배합사료 적정 공급률 김성삼·김강웅·김경덕·이봉주·한현섭·김재원·배승철·이경준*

Optimum Feeding Rate in Growing Olive Flounder Paralichthys olivaceus Fed Practical Expanded Pellet at Optimum Water Temperature (19-21℃)

We investigated the effects of feeding rate on the growth performance, blood components, and histology of growing olive flounder Paralichthys olivaceus. We determined the optimum feeding rate (initial fish mean weight of g) at the optimum water temperature. Two replicated groups of fish were fed a commercial diet at rates of 0%, 0.5%, 0.75%, and 1.0% body weight (BW) per day, and to satiation. Feeding trial was conducted using a flow-through system with 10 1.2-metric ton aquaria receiving filtered seawater at for three weeks. Weight gain (WG) for fish fed to satiation was significantly higher than that of unfed fish and fish fed at 0.5% and 0.75% BW per day. The WG of fish fed at 1.0% BW per day was significantly higher than that of unfed fish and of fish fed at 0.5% BW per day. However, there were no significant differences in WG between fish fed at 0.5% BW per day and those fed at 0.75% BW per day, between fish fed at 0.75% BW per day and those fed at 1.0% BW per day, and between fish fed at 1.0% BW per day and those fed to satiation. The specific growth rates of fish fed at 1.0% BW per day and those fed to satiation were significantly higher than those of unfed fish and of fish fed at 0.5% BW per day. Broken-line regression analysis of weight gain showed that the optimum feeding rate of olive flounder weighing 240 g was 1.09% BW per day at the optimum water temperature.

Optimum Feeding Rate for Growing Olive Flounder (317 g) Paralichthys olivaceus Fed Practical Extruded Pellets at Optimum Water Temperature (21-24℃)

We investigated the effects of feeding rate on the growth performance, blood components, and histology of grow-ing olive flounder Paralichthys olivaceus. Optimum feeding rate (initial fish mean weight : 316.7±6.18 g) was de-termined under the optimum water temperature. Two replicated groups of fish were fed a commercial diet at rates of 0%, 0.4%, 0.6%, and 0.8% of body weight (BW) per day, and to satiation. Feeding trial was conducted using a flow-through system with 10 1.2-metric ton aquaria receiving filtered seawater at 21-24°C for 3 weeks. Weight gain (WG) and specific growth rate (SGR) were significantly higher in fish fed to satiation (1.0% BW/day) than in those in other treatments. These parameters were negative and significantly lower in the starved fish than in fish fed the experimental diet at all feeding rates. There were no significant differences in WG and SGR among fish fed at 0.4%, 0.6%, and 0.8% BW/day. Hematocrit and hemoglobin in fish fed to satiation were significantly lower than those in other treatments. Histological changes of fish fed at 0.6% BW/day indicated that this group was in the best condition; differences were not found in tissues of fish fed at 0%, 0.6% and 1.0% BW/day. Broken-line regression analysis of weight gain showed that the optimum feeding rate of olive flounder weighing 317 g was 0.99% BW per day at the optimum water temperature.Key words: Olive flounder, Feeding rate, Optimum water temperature, Histology, Hepatopancreas

Effects of Dietary Supplementation of Fermented Garlic Powder and Fluid on Growth Performance, Immune Responses, Blood Components, and Disease Resistance against Edwardsiella tarda and Streptococcus iniae in Olive Flounder Paralichthys olivaceus

Two consecutive studies were conducted to evaluate the effects of dietary supplementation with fermented garlic powder (FGP) or fermented garlic fluid (FGF) on growth performance, immune responses, and disease resistance of olive flounder Paralichthys olivaceus. In experiment I, olive flounder (BW: 65 g) were fed four experimental diets formulated to contain 0%, 0.5%, 1%, and 1.5% FGP (designated as FGP-0, FGP-0.5, FGP-1, and FGP-1.5, respec-tively). After the 10-weeks feeding trial, feed intake was significantly lower in fish fed the FGP-0.5 and FGP-1.0 diets, as compared to those fed the control diet. Fish fed the FGP-0 and FGP-0.5 diets showed significantly lower survival, as compared to the other treatments. Dietary supplementation with FGP resulted in higher non-specific immune re-sponses than the FGP-0 group. Plasma cholesterol and triglyceride levels decreased as dietary FGP level increased. In experiment II, olive flounder (BW: 65 g) were fed four experimental diets for 10 weeks. The diets were prepared with a commercial expanded pellet to have 0%, 0.25%, 0.5%, and 1% FGF (designated as FGF-0, FGF-0.25, FGF-0.5, and FGF-1, respectively) by adsorption. At the end of the second feeding trial, feed intake was significantly lower in fish fed the FGF-0 diet, as compared to other treatments. Fish fed the FGF-0.25 and FGF-0.5 diets exhibited significantly lower cholesterol levels, as compared to other treatments. Lysozyme activity significantly increased with increases in dietary FGF. Cumulative mortality in a challenge test with Streptococcus iniae was significantly lower in the fish groups fed FGF-supplemented diets than in fish fed the control diet. The results of this study indicated that dietary supplementation with FGP or FGF can enhance the non-specific immune responses and disease resistance of olive flounder against S. iniae.Key words: Olive flounder, Fermented garlic powder, Fermented garlic fluid, Challenge test, Non-specific immune response