• Fisheries and Aquatic Sciences
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• v.1 no.2
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• pp.255-259
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• 1998

This study was designed to evaluate the economic analysis of channel catfish production in 1998 based on fish value and total feed cost. Catfish received higher protein feeds with lesser amount based on the dietary protein levels, but received the constant total protein input for all treatments. Weight gain per pond for treatment 1 $(28\%\;protein,\;100\%\;of\;satiation)$ was higher (P<0.10) than for treatment 3 $(36\%\;protein,\;77.8\%\;of\;satiation)$, but not significantly higher than for treatment 2 $(32\%\;protein,\;87.5\%\;of\;satiation)$ at constant DE. At constant DE/P (treatments 4, 2 and 5), weight gain per pond for treatment 5 $(36\%\;protein,\;77.8\%\;of\;satiation)$ was lower (P<0.10) than for treatment 2, but not significantly lower than for treatment 4 $(28\%\;protein,\;100\%\;of\;satiation)$. At constant DE, feed conversion slightly improved as dietary protein level increased from $28\%\;to\;32\%$ and feed allowance decreased by $12.5\%$, but did not improve further as dietary protein level increased from $28\%\;to\;36\%$ and feed allowance decreased by $22.2\%$. At constant DE/P, feed conversion improved as dietary protein level increased from $28\%\;to\;32\%$ increased and feed allowance decreased by $12.5\%$, but did not improve as dietary protein level increased from $28\%\;to\;36\%$ and feed allowance decreased by $22.2\%$ Total feed cost for treatment 1 was slightly, but not significantly higher than for treatments 2 and 3 at constant DE. At constant DE/P, total feed cost for treatment 5 was higher (P<0.05) than for treatment 2, but not significantly higher than for treatment 4. Total value of fish ($ /ha) produced for treatment 1 was highest and lowest was for treatment 5. Return above feed cost was highest for treatment 1 and nearly the same as treatment 2. Return over feed cost for treatments 3 and 4 were slightly lower than for treatments 1 and 2. Economic analysis showed that feeding fish the diet containing $28\%$ protein and 3.08 kcal/g DE to satiation and the diet containing $32\%$ protein and 3.08 kcal/g DE to $87.5\%$ of satiation produced the highest profit to farmer.

• Journal of Aquaculture
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• v.21 no.4
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• pp.244-251
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• 2008

We evaluated the optimum dietary lipid level and feeding rates of extruded pellets (EP) in juvenile flounder Paralichthys olivaceus during the summer season. The first experiment was conducted to determine the optimum dietary lipid level in juvenile flounder. Five isonitrogenous EP (52% crude protein) with increasing dietary lipids (6, 8, 10, 12 and 14%) were fed to satiety to triplicate groups of the juveniles ($18.4{\pm}0.11g$) twice a day for 6 weeks. Weight gain (WG) of fish fed EP with 10% lipid was significantly higher than those of fish fed EP with 6 and 14% lipid (P<0.05). Broken line model analysis suggested that the optimum dietary lipid level could be $9.08{\pm}0.37%$ for the maximum WG in juvenile flounder. The second experiment was conducted to determine the optimum feeding rate using experimental diet contained 10% lipid level that had the highest WG in first experiment. The feed intake of triplicate groups of the juveniles ($13.4{\pm}0.15g$) was restricted to four different feeding rates of 2.0, 2.5, 3.0 and 3.5% of their body weight $day^{-1}$ and to satiation using experimental diets. WG and feed efficiency (FE) of fish was affected by feeding rates. WG and specific growth rate of fish fed the diets increased with increasing feeding rate, however no significant differences (P>0.05) in WG and specific growth rate were observed between the fish fed 3.5% of their body weight $day^{-1}$ and to satiation. FE of fish fed 3.5% of their body weight $day^{-1}$ was significantly higher than those offish fed 2.0% of their body weight $day^{-1}$ and to satiation (P<0.05). Broken line model analysis suggested that the optimum dietary feeding rate could be $3.56{\pm}0.06%$ for the maximum WG in juvenile flounder. These results indicated that the optimum lipid level and feeding rate could be $9{\sim}10%$ (Energy: 4,774kcal and PIE ratio: 108mg protein/kcal in diet) and 3.5% of their body weight $day^{-1}$in juvenile flounder, respectively.

• Journal of Life Science
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• v.19 no.2
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• pp.277-283
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• 2009

Biogenic amines are generally formed through the decarboxylation of specific free amino acids by exogenous decarboxylases released by microbial species associated with the fish products and fermented feeds. This study was conducted to investigate the properties of e tuna waste regarding the control of degradation of biogenic amines (histamine, tyramine, tryptamine, putrescine, and cadaverine) that might be related with the anti-nutritional factor of the tuna waste that is used for manufacturing domestic fish meal. The values of pH and the salt content were 6.51, 3.35% in tuna waste and 5.58 and 5.83% in tuna fish meal, respectively. The strains and dominant bacteria tested in the tuna waste sample were 9.20, 9.29, 5.67, 7.82 and 7.58 log CFU/g of total bacteria, aerobic plate count (APC), total coliform (TC), Lactobacillus spp. and Bacillus spp., respectively. The main histamine forming-bacteria (HFB) in tuna waste were detected by silica gel thin-layer chromatography (TLC) and 7 histamine-forming bacterial species were isolated among microbes grown in selective medium. The histamine concentration was determined by detection of fluorescence of ο-phthaldialdehyde (OPA) derivatives using HPLC and the date were used to reconfirm the identities of the amine-producing bacteria. The 15 histamine- forming bacteria strains grown in trypicase soy broth (TSB) supplemented with 1% L-histidine (TSBH) were identified as Lactococcus(L.) lactis subsp. lactis, Klebsiella pneummonlae, L. garvieae 36, Vibrio olivaceus, Hafnia alvei and L. garvieae which were main dominant amine - producing strains, and Morganella morganii identified by 16S ribosomal RNA (rRNA) sequencing with PCR amplification. A Phylogenetic tree generated from the 16S rRNA sequencing data showed different phyletic lines that could be readily classified as biogenic amine forming gram-positive and negative bacteria.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.6
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• pp.861-882
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• 2000

The seed, or grain, of modern cultivars of Lupinus angustifolius, commonly known as Australian sweet lupins (ASL), is an established feed resource for the intensive animal industries of Australia, Japan, Korea and several other countries in Asia and Europe. Since the introduction of ASL to the world marketplace about 25 years ago, researchers in many countries have found them to be a valuable component of the diet of beef and dairy cattle, sheep, pigs, poultry, finfish and crustaceans. The seed of ASL contains ~32% crude protein (CP) (~35% DM basis) and 5% oil. The main storage carbohydrates in the seed are the ${\beta}$-galactans that comprise most of the cell-wall material of the kernel and the cellulose and hemicellulose of the thick seed coats. ASL seeds contain about 40% non-starch polysaccharides (NSP) and a negligible amount of starch. This makes them an excellent ingredient for ruminant diets, as the risk of acidosis is very low. The seed of modern cultivars of domesticated Lupinus species contain negligible amounts of lectins and trypsin inhibitors so they do not require preheating before being used as an ingredient in feeds for monogastric species. They have a high digestibility coefficient for protein, >90% for most species, but a low energy digestibility, ~60%, which is mostly due to the high content of NSP. The low content of methionine (0.22%) and of lysine (1.46%) is typical of the legumes. The lysine availability for pigs is >70%. Lupin kernels contain ~39% CP (~42% DM basis), 6% oil and 30% NSP. They have a higher digestible energy for pigs and finfish and a higher metabolisable energy for poultry than whole seed. Commercial operations rarely achieve complete separation of kernel from hull and it is more likely that the kernel fraction, called splits or meats, will contain ~36% CP. The replacement of soybean meal or peas with ASL in cereal-based diets for most intensively reared animals, birds and fish is possible provided lysine, methionine and digestible energy levels are kept constant. This makes ASL economically competitive in many, but not all, circumstances.

• Fisheries and Aquatic Sciences
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• v.19 no.3
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• pp.12.1-12.8
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• 2016

Roe is the term used to describe fish eggs (oocytes) gathered in skeins and is one of the most valuable food products from fishery sources. Thus, means of processing are required to convert the underutilized yellowfin tuna roes (YTR) into more marketable and acceptable forms as protein concentrate. Roe protein concentrates (RPCs) were prepared by cooking condition (boil-dried concentrate, BDC and steam-dried concentrate, SDC, respectively) and un-cooking condition (freeze-dried concentrate, FDC) from yellowfin tuna roe. The yield of RPCs was in the range from 22.2 to 25.3 g/100 g of roe. RPCs contained protein (72.3-77.3 %), moisture (4.3-5.6 %), lipid (10.6-11.3 %) and ash (4.3-5.7 %) as the major constituents. The prominent amino acids of RPCs were aspartic acid, 8.7-9.2, glutamic acid, 13.1-13.2, and leucine, 8.5-8.6 g/100 g of protein. Major differences were not observed in each of the amino acid. K, S, Na, and P as minerals were the major elements in RPCs. No difference noted in sodium dodecyl sulfate polyacrylamide gel electrophoresis protein band (15-100 K) possibly representing partial hydrolysis of myosin. Therefore, RPCs from YTR could be use potential protein ingredient for human food and animal feeds.

• Journal of Fisheries and Marine Sciences Education
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• v.20 no.1
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• pp.90-94
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• 2008

Growth and water quality in Japanese eel, Anguilla japonica ($6.0{\pm}0.9g$) fed extruded and paste type diets were compared for 8 weeks. Fish in the duplicate tanks were fed with one of three experimental diets: two different extruded pellet diets and one paste type diet. Six FRP tanks were used with stocking density of 3.6 kg per tank (3 m3). Restricted feeds (ca. 2% of body weight) were served twice daily. Weight gains were checked at the end of every two-week interval, and water qualities in terms of NH4-N and NO2-N were determined daily one hour after feeding in the morning. Water temperature, dissolved oxygen, and pH were constantly kept within the optimum range, while fifty percent of total water volume was changed daily. Eels fed the extruded pellet diets showed significantly better (P<0.05) growth performance than did eels fed the paste type diet. The amount of feed waste from the paste type diet was significantly greater than those from the extruded pellet diets (P<0.05). Ammonia (NH4-N) waste was significantly higher from the paste diet than from the extruded pellet diets (P<0.05). These results show that extruded pellet diets are better than the paste type diet for growth and water quality management in eel culture.

• Ocean and Polar Research
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• v.41 no.4
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• pp.289-309
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• 2019

Marine microalgae have long been used as food additives and feeds for juvenile fish and invertebrates as their nutritional content is beneficial for humans and marine aquaculture species. Recently, they have also been recognized as a promising source for cosmeceutical, nutraceutical, and pharmaceutical products as well as biofuels. Marine microalgae of various species are rich in multiple anti-oxidant phytochemicals and their bioactive components have been employed in cosmetics and dietary supplements. Oil contents in certain groups of marine microalgae are extraordinarily rich and abundant and therefore have been commercialized as omega-3 and omega-6 fatty acid supplements and mass production of microalgae-based biodiesels has been demonstrated by diverse research groups. Numerous natural products from marine microalgae with significant biological activities are reported yearly and this is attributed to their unique adaptive abilities to the great diversity of marine habitats and harsh conditions of marine environments. Previously unknown toxin compounds from red tide-forming dinoflagellates have also been identified which opens up potential applications in the blue biotechnology sector. This review paper provides a brief overview of the biotechnological potentials of Korean marine microalgae. We hope that this review will provide guidance for future marine biotechnology R&D strategies and the various marine microalgae-based industries in Korea.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.50 no.1
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• pp.15-24
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• 2017

This study examined the effects of dietary supplementation with citrus by-product (CBP) on the growth, feed utilization, innate immunity, and histology of the gills and intestine of juvenile olive flounder Paralichthys olivaceus during low water temperature season. A vitamin C-free basal diet was regarded as a control and five other diets were formulated that contained 30 and 300 mg of L-ascorbyl-2-polyphosphate (LAPP) or CBP as vitamin C equivalents/kg diet, or the antibiotic oxytetracycline (OTC) (designated as control, LAPP30, LAPP300, CBP30, CBP300, and OTC, respectively). Olive flounder (initial body weight $44.6{\pm}0.32g$) were fed the six experimental diets to apparent satiation for 9 weeks. Growth and feed utilization were significantly higher in CBP30 than in the control and LAPP groups. The lysozyme activity was significantly higher in CBP30 than in LAPP300. Enterocyte height was significantly higher in CBP30 than in the control. The number of goblet cells was increased significantly with LAPP30, LAPP300, and CBP30. These results demonstrate that CBP can reduce or replace vitamin C and antibiotic in the diet of olive flounder during the low-water-temperature season. The optimal CBP supplementation level seems to be approximately 1%, which is equivalent to 30 ppm vitamin C/kg in the fish diet.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.1153-1153
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• 2001

Directive 79/373/EEC on the marketing of compound feeding stuffs, provided far a flexible declaration arrangement confined to the indication of the feed materials without stating their quantity and the possibility was retained to declare categories of feed materials instead of declaring the feed materials themselves. However, the BSE (Bovine Spongiform Encephalopathy) and the dioxin crisis have demonstrated the inadequacy of the current provisions and the need of detailed qualitative and quantitative information. On 10 January 2000 the Commission submitted to the Council a proposal for a Directive related to the marketing of compound feeding stuffs and the Council adopted a Common Position (EC N$^{\circ}$/2001) published at the Official Journal of the European Communities of 2. 2. 2001. According to the EC (EC N$^{\circ}$ 6/2001) the feeds material contained in compound feeding stufs intended for animals other than pets must be declared according to their percentage by weight, by descending order of weight and within the following brackets (I :< 30%; II :> 15 to 30%; III :> 5 to 15%; IV : 2% to 5%; V: < 2%). For practical reasons, it shall be allowed that the declarations of feed materials included in the compound feeding stuffs are provided on an ad hoc label or accompanying document. However, documents alone will not be sufficient to restore public confidence on the animal feed industry. The objective of the present work is to obtain calibration equations fur the instanteneous and simultaneous prediction of the chemical composition and the percentage of ingredients of unground compound feeding stuffs. A total of 287 samples of unground compound feeds marketed in Spain were scanned in a FOSS-NIR Systems 6500 monochromator using a rectangular cup with a quartz window (16 $\times$ 3.5 cm). Calibration equations were obtained for the prediction of moisture ($R^2$= 0.84, SECV = 0.54), crude protein ($R^2$= 0.96, SECV = 0.75), fat ($R^2$= 0.86, SECV = 0.54), crude fiber ($R^2$= 0.97, SECV = 0.63) and ashes ($R^2$= 0.86, SECV = 0.83). The sane set of spectroscopic data was used to predict the ingredient composition of the compound feeds. The preliminary results show that NIRS has an excellent ability ($r^2$$\geq$ 0, 9; RPD $\geq$ 3) for the prediction of the percentage of inclusion of alfalfa, sunflower meal, gluten meal, sugar beet pulp, palm meal, poultry meal, total meat meal (meat and bone meal and poultry meal) and whey. Other equations with a good predictive performance ($R^2$$\geq$0, 7; 2$\leq$RPD$\leq$3) were the obtained for the prediction of soya bean meal, corn, molasses, animal fat and lupin meal. The equations obtained for the prediction of other constituents (barley, bran, rice, manioc, meat and bone meal, fish meal, calcium carbonate, ammonium clorure and salt have an accuracy enough to fulfill the requirements layed down by the Common Position (EC Nº 6/2001). NIRS technology should be considered as an essential tool in food Safety Programs.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.3
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• pp.319-328
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• 1997

To develop a beneficial microbial feed for the cultivation of rotifer, Brachionus plicatilis, an aerobic photosynthetic bacterium, Erythrobacter sp. $S\;\pi-I$ was isolated from marine structure at Haeundae beach in Pusan, Korea. Feeding effects of Erythrobacter sp. $S\;\pi-I$ on the growth of rotifer were analyzed comparing to other feeds such as PSB (purple nonsulfur bacteria), Chlorella sp. and baker's yeast. Erythrobacter sp. $S\;\pi-I$ contained more linoleic acid $(C_{18:3\omega3})$ and oleic acid $(C_{18:1\omega9})$ and amino acids than PSB (purple nonsulfur bacteria), Chlorella sp. and baker's yeast. The rotifer fed on Erythrobacter sp. $S\;\pi-I$ showed better effects than those fed on other feeds in the individual growth, size and weight. Also, the rotifer especially contained more eicosapentaenoic acid $(C_{20:5\omega3})$ and docosahexaenoic acid $(C_{22:6\omega3})$ in case of Erythrobacter sp. $S\;\pi-I$ feeding than the other feeds. In case of the feed of PSB and baker's yeast docosahexaenoic acid $(C_{22:6\omega3})$ did not show. In amino acid analysis, the rotifer fed on Erthrobacter sp, $S\;\pi-I$ showed more amino acid content comparing to those fed on other diets. Especially, arginine, isoleucine, histidine, lysine, methionine, phenylalanine, threonine, which are essential amino acid for fish growth, showed high contents. These results suggested that the aerobic photosynthetic bacterium, Erythrobacter sp. $S\;\pi-I$ would be a beneficial microbial teed for the cultivation of rotifer.