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REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
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Korean Journal of Fisheries and Aquatic Sciences
Journal Basic Information
Journal DOI :
The Korean Society of Fisheries and Aquatic Science
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Volume & Issues
Volume 46, Issue 6 - Dec 2013
Volume 46, Issue 5 - Oct 2013
Volume 46, Issue 4 - Aug 2013
Volume 46, Issue 3 - Jun 2013
Volume 46, Issue 2 - Apr 2013
Volume 46, Issue 1 - Feb 2013
Selecting the target year
A Study of Nitrification Kinetics in the Biofilter Process for Aquaculture Water Treatment: A Review
Park, Noh Back ; Park, Mi Seon ; Lee, Jin Hwan ; Myeong, Jeong In ;
Korean Journal of Fisheries and Aquatic Sciences, volume 46, issue 6, 2013, Pages 675~681
DOI : 10.5657/KFAS.2013.0675
There have been many studies on biofilter process regarding satisfactory water quality and the operational conditions of Recirculating Aquaculture Systems (RAS). For effective nitrification processes, it is necessary to dynamically identify and apply nitrifying microorganisms. Physical, chemical and biological processes concerning biofilms can be applied and influential factors including substrate, dissolved oxygen concentrations, organic matter, temperature, pH, alkalinity, salinity and mixing velocity intensity need to be considered. Also, designing and managing the process based on the dynamic interpretation of these factors are prerequisites for engineering applications of the biofilter process. This paper draws on current literature on the kinetics of nitrification of biofilms in the biofilter process. Influential factors for nitrification are crucial during the biofilter process and are expected to be critical in informing the design and operation of recirculating aquaculture systems.
Effects of Krill Euphausia superba Fluoride Extract on Toxicity and Oxidative Stress in Liver cell
Kim, Jeong Gyun ; Yoon, Ho Dong ; Park, Sihyang ; Kim, Poong Ho ; Mok, Jong Soo ; Hong, Yumi ;
Korean Journal of Fisheries and Aquatic Sciences, volume 46, issue 6, 2013, Pages 682~688
DOI : 10.5657/KFAS.2013.0682
In this study, we investigated about cell toxicity and oxidative stress of HepG2 cell by treatment of sodium fluoride (NaF) and fluoride extracts from krill Euphausia superba meat, shell, whole body and krill meal. The cell toxicity showed significant at 300 and
NaF treatment group. But krill (Euphausia superba) fluoride extract (KFE) treatment in all groups were not toxic. The superoxide radical production increased significantly in NaF treated group, but there was no significant change in KFE treated group. The superoxide dismutase activity was a significant increase 21.5% at
and 24.7% at
treatment group of fluoride extracts from krill meat, and 8.7% at
in krill meals, compared to the control group. However, hydroxy radical flux and catalase and glutathione peroxidase activity of fluoride extracts from krill meat did not change. As a result, for a short period of time, NaF treatment in HepG2 cells affect the cell toxicity and oxidative stress, but in the case of KFE, these were not recognized. Thus, depending on the type of food ingested with fluoride, cell toxicity and oxidative stress was found to be different.
Optimal Fermentation Conditions (Temperature and Salt Concentration) for Preparing Flounder Verasper moseri Jordan et Gilberu Sikhae
Han, Dae-Won ; Han, Ho-Jun ; Kim, Deok-Gi ; Im, Mi-Jin ; Cho, Soon-Yeong ;
Korean Journal of Fisheries and Aquatic Sciences, volume 46, issue 6, 2013, Pages 689~695
DOI : 10.5657/KFAS.2013.0689
Flounder Verasper moseri Jordan et Gilberu sikhae is a traditional salt-fermented food in Korea. We investigated the optimal processing conditions for desirable quality-controlled flounder sikhae by analyzing the physiochemical properties, microbiological species, and organoleptic properties. The optimal fermentation temperature, salt concentration, and fermentation period for preparing flounder sikhae of acceptable quality were
, 4%, and 14 days, respectively. The amino-N and volatile basic nitrogen (VBN) contents of rhe acceptable quality flounder sikhae were 243.65 mg/100 g and 44.25 mg/100 g, respectively.
Quality Characterization of Commercial Flounder Verasper moseri Jordan et Gilberu Sikhae
Han, Dae-Won ; Han, Ho-Jun ; Kim, Deok-Gi ; Im, Mi-Jin ; Cho, Soon-Yeong ;
Korean Journal of Fisheries and Aquatic Sciences, volume 46, issue 6, 2013, Pages 696~701
DOI : 10.5657/KFAS.2013.0696
Flounder Verasper moseri Jordan et Gilberu sikhae is one of the traditional Korean fermented food. Microbiological, chemical, and biogenic amine analyses were carried out to evaluate the quality of commercial flounder sikhae and establish standardization. The quality characteristics were analyzed in terms the salinity, volatile basic nitrogen, pH, amino-N, TBA value, biogenic amine, viable cell count, and lactic acid bacteria. Quality evaluation of commercial flounder sikhae revaled an average pH of 4.84, volatile basic nitrogen of 43.47 mg/100 g, amino-N of 213.04 mg/100 g, salinity of 5.77 %, viable cell count of
, viable lactic acid bacteria count of
and biogenic amine level of 0.70-47.34 mg/kg.
Stress Relaxation and Sleep Induction Effect of Fermented Sea Tangle Saccharina japonica and Oyster Crassostrea gigas Powder
Woo, Nam-Sik ; Seo, Yong Bae ;
Korean Journal of Fisheries and Aquatic Sciences, volume 46, issue 6, 2013, Pages 702~707
DOI : 10.5657/KFAS.2013.0702
Sleep is an essential biological process of which the underlying regulatory mechanisms involve numerous anatomical structures and biochemical substances that can be compromised by stress and the immune system. Gamma aminobutyric acid (GABA) is the main inhibitory neurotransmitter of the central nervous system (CNS). It is well established that activation of
receptors promotes sleep. L. brevis BJ20 fermentation of sea tangle and oysters resulted in stress reduction and sleep inducing effects. This is the first study to report that GABA has the ability to induce sleep related hormones in mice; therefore, it has potential use as a natural sleep aid. These results suggested that sea tangle and oysters fermented by L. brevis BJ20 can be used as potential agents for stress reduction and sleep promotion.
Changes in Proximate Composition and Lipid Components in Chub Mackerel Scomber japonicus and Japanese Jack Mackerel Trachurus japonicus with Various Cooking Methods
Moon, Soo-Kyung ; Kang, Ji-Yeon ; Kim, In-Soo ; Jeong, Bo-Young ;
Korean Journal of Fisheries and Aquatic Sciences, volume 46, issue 6, 2013, Pages 708~716
DOI : 10.5657/KFAS.2013.0708
Changes in the proximate composition, lipid classes, and fatty acids were studied in chub mackerel Scomber japonicus and Japanese jack mackerel Trachurus japonicus muscles cooked using a frying pan, oven, and microwave oven. The moisture content was high in the raw samples (chub mackerel 65.5%, Japanese jack mackerel 60.5%) and decreased with cooking, especially in the frying pan method (chub mackerel 49.2%, Japanese jack mackerel 49.8%). In contrast, the protein, lipid and ash contents increased significantly with cooking in chub mackerel muscle (P<0.05). However, the lipid content of Japanese jack mackerel muscle showed no significant difference between the samples using the three cooking methods and the raw sample. The dripped lipid contents from the cooked muscles showed the highest levels in the frying pan samples and the lowest levels in the microwave oven samples. The percentage of non-polar lipid (NL) in the total lipid content was over 95% in the muscle lipids (10.43-21.86 g/100 g sample). Prominent fatty acids were 16:0, 18:1n-9, 22:6n-3 (docosahexaenoic acid, DHA), 16:1n-7 and 20:5n-3 (eicosapentaenoic acid, EPA) in both fish muscles and dripped lipids. There was no change in the EPA level in any of the fish muscles, by any cooking method. The percentage of DHA in the muscle of chub mackerel showed the lowest level in the frying pan sample and the highest level in the microwave oven and raw samples, and an intermediate level in the oven sample. However, the percentage of DHA in the Japanese jack mackerel muscle was not significantly different between the various cooking methods. From these results, the microwave oven and oven cooking methods showed relatively low levels of dripped lipid content and loss of n-3 PUFA compared with the frying pan cooking method.
Food Component Characteristics of Wild Hard-shelled Mussel Mytilus coruscus and Cultured Sea Mussel Mytilus edulis in Korea
Kim, Seon-Geun ; Lee, So-Jeong ; Oh, Kwang-Soo ;
Korean Journal of Fisheries and Aquatic Sciences, volume 46, issue 6, 2013, Pages 717~724
DOI : 10.5657/KFAS.2013.0717
To characterize the food components of two mussels (wild hard-shelled mussel (HM) Mytilus coruscus, and cultured sea mussel (SM) Mytilus edulis) in Korea, we examined the proximate composition, fatty composition, amino acid/mineral content, texture, collagen content and chemical and taste compounds. Regarding the proximate composition, HM had lower moisture levels and higher crude protein and carbohydrate contents than SM. The amino nitrogen, volatile basic nitrogen and total amino acid contents of HM and SM were 250.6 and 227.3 mg/100 g, 11.2 and 12.0 mg/100 g, and 17,451.1 and 15,334.8 mg/100 g, respectively. The major amino acids were glutamic acid, aspartic acid, glycine, alanine, lysine and arginine. The major fatty acids of HM and SM were 14:0, 16:0, 16:1n-7, 20:5n-3, and 22:6n-3, which did not differ significantly between the two mussels. HM had a higher n-3 polyene ratio, and a lower saturate and monoene ratio than SM. Regarding the taste-active compounds, the free amino acid contents of HM and SM were 1,116.5 and 961.8 mg/100 g, respectively, and the major free amino acids were taurine, glutamic acid, glutamine, glycine, citrulline, lysine and arginine. The primary minerals in both HM and SM were Na, Cl, K and P which did not differ significantly between the two mussels. The soluble and insolube collagen contents of HM and SM were 265.8 and 228.4 mg/100 g, and 119.5 and 121.8 mg/100 g, respectively.
Comparisons of Food Component Characteristics of Wild and Cultured Edible Pufferfishes in Korea
Hwang, Seok-Min ; Oh, Kwang-Soo ;
Korean Journal of Fisheries and Aquatic Sciences, volume 46, issue 6, 2013, Pages 725~732
DOI : 10.5657/KFAS.2013.0725
To identify the food component characteristics of seven edible pufferfishes (five wild pufferfishes including striped puffer Takifugu xanthopterus; eyespot puffer Takifugu chinensis; purple puffer Takifugu porphyreus; rough-backed puffer Lagocephalus wheeleri; and grass puffer Takifugu niphobles; and two cultured pufferfishes including yellow puffer Takifugu obscurus, and tiger puffer Takifugu rubripes) in Korea, the proximate, fatty/amino acid, chemical and taste compositions were investigated. The proximate compositions were not significantly different among the sampled pufferfishes, whereas grass puffer had lower moisture and crude lipid levels contents, and higher crude protein and ash contents than the other species. The total amino acid levels in wild and cultured pufferfishes were 14,941.6-16,427.9 mg/100 g, and the major amino acids were aspartic acid, glutamic acid, glycine, alanine, leucine, lysine and arginine. Regarding the fatty acid and mineral compositions, the major fatty acids included 22:6n-3, 16:0, 18:1n-9, 20:5n-3, 18:0, 20:4n-3, and 22:5n-3 in that order, and there was a little difference among the sampled pufferfishes. Grass puffer had a higher monoenes ratio, i.e., 16:1n-7 and 18:1n-9, and a lower polyenes ratio than the other pufferfishes. The main minerals detected K, P, Na, S and Ca. Regarding the taste-active compounds, the free amino acid contents of pufferfish extracts were 236.4-428.1 mg/100 g, consisting primarily of taurine, lysine, proline, glycine, alanine and arginine in that order. The amino nitrogen content of the pufferfishes was 84.5-156.4 mg/100 g, and there was a little difference among the species. As for taste intensity, the total taste value of the purple puffer was higher than that of the other pufferfishes.
Inhibitory Effect of High Hydrostatic Pressure Treatments on Histamine Production in Mackerel Scomber japonicus
Kang, Bo-Kyeong ; Kim, Koth-Bong-Woo-Ri ; Kim, Min-Ji ; Kim, Dong-Hyun ; Jung, Seul-A ; Bark, Si-Woo ; Pak, Won-Min ; Kim, Bo-Ram ; Park, Hong-Min ; Byun, Myung-Woo ; Ahn, Dong-Hyun ;
Korean Journal of Fisheries and Aquatic Sciences, volume 46, issue 6, 2013, Pages 733~738
DOI : 10.5657/KFAS.2013.0733
This study investigated the inhibitory effect of high hydrostatic pressure (HHP) treatments on histamine production in mackerel Scomber japonicus. Changes in viable cell counts, histamine contents, pH and VBN of mackerel fillet (stored at
for 25 days) were examined under HPP (200, 300, and 400 MPa). HPP treatments reduced viable cell counts by 2-3 log cycles during storage. Viable cells of mackerels treated with 400 MPa did not appear for 5 days. Histamine production was nearly suppressed by 300 and 400 MPa HPP treatments after 25 days. Furthermore, mackerels treated with HPP showed significantly lower VBN values compared with the control. Additionally, pH values were not affected by the treatments during storage periods. These results suggest that HPP treatment decreased histamine contents in mackerel muscles. Based on our results, HPP treatment may reduce scombroid fish poisoning by decreasing histamine production in mackerel during
Effects of Surimi and Starch on the Quality Properties of Mackerel Scomber japonicus Sausage
Kim, Koth-Bong-Woo-Ri ; Jeong, Da-Hyun ; Pak, Won-Min ; Kim, Bo-Ram ; Kang, Ja-Eun ; Park, Hong-Min ; Ahn, Dong-Hyun ;
Korean Journal of Fisheries and Aquatic Sciences, volume 46, issue 6, 2013, Pages 739~745
DOI : 10.5657/KFAS.2013.0739
This study was conducted to evaluate the qualities of mackerel Scomber japonicus sausage prepared with Theragra chalcogramma surimi (TS, A grade), Nemipterus virgatus surimi (NS, A grade) (0, 5, 7, 10%), and 7% NS with starch (0, 1, 2, 3%). The whiteness of the mackerel sausage was significantly increased by adding TS and NS, but that of the NS with starch groups was decreased compared with the control. The hardness increased significantly with the addition of TS, whereas the NS and NS with starch groups showed no considerable differences compared with the control. The gel strength was not significantly different among the mackerel sausage additive groups. In the sensory evaluation, the mackerel sausages containing 5% TS, 7% NS, and 7% NS with 2% starch had the highest overall preference. In conclusion, these results suggest that 5% TS, 7% NS, and 7% NS with 2% starch improve the quality, texture and sensory properties of mackerel sausage.
The Effect of Partial Replacement of Fish Meal by Squid Sepia esculenta Liver Powder on the Growth and Body Composition of Juvenile Black Rockfish Sebastes schlegeli
Moon Lee, HaeYoung ; Choi, Se-Min ;
Korean Journal of Fisheries and Aquatic Sciences, volume 46, issue 6, 2013, Pages 746~752
DOI : 10.5657/KFAS.2013.0746
An 8-week feeding experiment was conducted to evaluate three types of squid Sepia esculenta liver powder (SLP) as a dietary protein source for replacement of fish meal (FM) in the juvenile black rockfish, Sebastes schlegeli. For replacement of FM, six experimental diets were formulated with 5 or 10% of either of three types (A, B, C) of SLP: SLP-
, and SLP-
. One of the control diets contained 100% FM as the protein source, and the other was a commercial diet (Com). Fish with an average body weight of
) were allocated randomly in triplicate groups of 50 to aquaria and fed the experimental diets until satiation. The weight gain (WG) and specific growth rate (SGR) of fish fed the FM, SLP-
, and SLP-
diets were higher than those of fish fed the Com, SLP-
diets. No significant differences were observed in WG and SGR among the diet groups, with the exception of the SLP-
diet group. The feed efficiency (FE) and protein efficiency ratio (PER) of fish fed the SLP-
, and SLP-
diets did not differ from those fed the control diet. However, fish fed SLP-
had lower FE and PER than the fish fed the FM, commercial, SLP-
, and SLP-
diets. Both the SLP-A and SLP-B diets, but not the SLP-C diets, replaced up to 10% and 5% of FM for juvenile black rockfish, respectively. The results of this experiment provide information that will assist in formulating an inexpensive and practical diet containing SLP for juvenile black rockfish.
Optimum Feeding Rate and Frequency in Juvenile Korean Rockfish Sebastes schlegeli Fed a Commercial Diet
Lee, Jin-Hyeok ; Kim, Kang-Woong ; Lee, Bong-Joo ; Park, Gun-Hyun ; Lee, Jun-Ho ; Yun, Hyeon-Ho ; Bai, Sungchul C. ;
Korean Journal of Fisheries and Aquatic Sciences, volume 46, issue 6, 2013, Pages 753~760
DOI : 10.5657/KFAS.2013.0753
Two feeding trials were conducted to investigate the effects of feeding rate and frequency on growth performance and body composition of juvenile Korean rockfish Sebastes schlegeli reared at
. In the first trial, three replicate fish groups averaging
were fed a commercial diet with one of seven different daily feeding rates: 1.00%, 2.00%, 2.50%, 2.75%, 3.00%, 3.25%, and satiation (3.34%) based on body weight (BW). After four weeks of feeding, fish fed the 3% diet showed significantly higher weight gain (WG) and feed efficiency (FE) than fish that received the other feeding rates. In the second trial, the optimum feeding frequency was evaluated with three replicate fish groups averaging
. Fish were fed a commercial diet at 2.87% BW with six different daily feeding frequencies: 2, 3, 4, 5, 7, or 9 meals. After four weeks of feeding, WG, specific growth rate, FE, and protein efficiency rate in fish fed 3 meals
were significantly higher than those of fish fed 7 or 9 meals
. In both feeding trials, proximate composition of the entire body changed depending on the feeding rate or frequency. A broken-line regression analysis based on weight gain suggested that the optimum daily feeding rate and frequency for juvenile Korean rockfish at
was 2.9% BW
and 2-3 meals
Optimal Feeding Frequency for Juvenile Korean Rockfish Sebastes schlegeli Fed Commercial Diet at Two Different Water Temperatures
Lee, Jin-Hyeok ; Lee, Bong-Joo ; Kim, Kang-Woong ; Han, Hyon-Sob ; Park, Gun-Hyun ; Lee, Jun-Ho ; Yun, Hyeon-Ho ; Bai, Sungchul C. ;
Korean Journal of Fisheries and Aquatic Sciences, volume 46, issue 6, 2013, Pages 761~768
DOI : 10.5657/KFAS.2013.0761
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
. 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
. 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
water, but whole-body lipids in the fish fed four meals/day was higher than those fed two meals/day in
water. A second-order polynomial analysis based on WG suggested the optimal feeding frequency for juvenile Korean rockfish was five meals/day at
and six meals/day at
, indicating that fish reared in higher water temperature require higher feeding frequencies.
Dietary Fermented Soybean Meal as a Replacement for Fish Meal in Juvenile Olive Flounder Paralichthys olivaceus
Kim, Kang-Woong ; Kim, Kyoung-Duck ; Lee, Bong-Joo ; Lee, Jin-Hyeok ; Han, Hyon-Sob ; Koo, Ja-Wan ; Choi, Youn Hee ; Bai, Sungchul C. ;
Korean Journal of Fisheries and Aquatic Sciences, volume 46, issue 6, 2013, Pages 769~776
DOI : 10.5657/KFAS.2013.0769
This study evaluated fermented soybean meal (FSM) as a fish meal (FM) replacement and determined the appropriate amount of FSM in juvenile olive flounder diet. Twenty-four aquaria with a flowing-water system were stocked with fish averaging 20.9 g at a density of 25 fish/tank. Five experimental diets were prepared replacing FM with 0, 10, 20, 30, or 40% FSM based on FM protein (designated
, respectively). Two additional diets were prepared that replaced 30 or 40% of the FM with FSM with added amino acids (methionine and lysine) (designated
, respectively). Fish (triplicates) were fed one of the eight experimental diets (50% crude protein and 16.7 kJ available energy
diet) for 8 weeks. Survival did not differ among the treatments during the feeding experiment. There were no significant differences in weight gain (WG) or specific growth rate (SGR) among the fish fed diets with up to 30% of the FM replaced. However, fish fed
had a reduced WG and SGR, as compared to
(control) (P < 0.05). The feed efficiency and apparent digestibility showed a similar trend (P < 0.05). The proximate composition in the whole body of fish differed only between the control and
for the crude protein level and between the control and
for the crude lipid level. The whole-body amino acid composition did not differ among treatments. No significant differences were found between the diet groups with and without amino acid supplementation, indicating that amino acid supplementation had no effect. The major finding of this study is that fermented soybean meal may replace up to 30% of fish meal without amino acid supplementation for normal growth of juvenile olive flounder.
Effects of Different Pellets on the Growth, Flesh Quality and Histopathological Changes of growing Korean Rockfish Sebastes schlegeli
Kim, Kyoung-Duck ; Kim, Kang-Woong ; Lee, Bong-Joo ; Bae, Ki-Min ; Seo, Jung Soo ; An, Cheul Min ; Han, Hyun-Sob ;
Korean Journal of Fisheries and Aquatic Sciences, volume 46, issue 6, 2013, Pages 777~784
DOI : 10.5657/KFAS.2013.0777
This study compared the effects of diets consisting of experimental extruded pellets (EP), commercial soft extruded pellets (SEP), and raw-fish-based moist pellets (MP) on the growth, flesh quality, and histology of the Korean rockfish Sebastes schlegeli. Three replicated groups of 60 fish each (initial mean weight 152 g) were fed one of two experimental EPs (EP1 and EP2), two commercial SEPs (SEP1 and SEP2), or MP for 11 weeks. The survival, weight gain, and final mean weight of the fish did not differ significantly among the groups. The highest feed efficiency was in fish fed MP (P<0.05), and the protein efficiency ratio of fish fed MP was significantly higher than that of fish fed EP1, EP2, or SEP1, but not significantly different from that of fish fed EP2. The daily feed intake of the fish fed the EPs and SEPs was significantly higher than that of the fish fed MP (P<0.05). The condition factor, Hepatosomatic Index, and Viscerasomatic Index of the fish did not differ significantly among the groups. No notable differences in the textural properties of the dorsal muscle, plasma biochemical parameters, or histological features of the fish were observed in fish fed any diet. This suggests that extruded pellets can be used to feed growing Korean rockfish without compromising growth, flesh quality, or histopathological change in comparison to raw fish-based moist pellets.
Effects of Dietary Nucleotide Supplementation on the Growth Performance, Feed Utilization, Hematological Parameters and Innate Immunity in Red Seabream Pagrus major
Song, Jin-Woo ; Lee, Kyeong-Jun ;
Korean Journal of Fisheries and Aquatic Sciences, volume 46, issue 6, 2013, Pages 785~792
DOI : 10.5657/KFAS.2013.0785
Two studies were conducted to investigate the effects of dietary nucleotides (NT) on the growth performance, hematological parameters, and innate immune responses of red seabream Pagrus major. In Expt I, six experimental diets were formulated: a control, four that contained each NT at a level of 0.15% (inosine monophosphate, IMP; adenosine monophosphate, AMP; guanosine monophosphate, GMP; and uridine monophosphate, UMP), and one with a 1:1:1:1 mixture of NTs (IMP, AMP, GMP, and UMP). In Expt II, five experimental diets were formulated that contained 0, 0.1, 0.2, 0.4, and 1.0% IMP (commercial product). Triplicate groups of juvenile (initial body weight 33.1 g) and growing (initial body weight 120 g) red seabream were fed one of the experimental diets to apparent satiation for 8 weeks in Expt I and 12 weeks in Expt II. In Expt I, fish fed diets with NT had higher growth performance than the control group. The nitroblue tetrazolium and lysozyme activities were higher in fish fed the mixed-NT diet, and lowest in the control group. In Expt II, the final body weight and feed utilization of fish fed the 0.1% IMP diet were significantly higher than those of fish fed the control or 1.0% IMP diets. Diet palatability was improved significantly when 0.1% IMP was added. The lysozyme activity was higher in fish fed diets with 0.4-1.0% than in the control group. These results suggest that supplementation of 0.15% IMP and Mixed-NTs in diet can enhance the growth and immune responses in juvenile red seabream. The optimum IMP level appears to be 0.2% in practical feed formulation for growing red seabream.
Physiological and Histological Characteristics of Starry Flounder Platichthys stellatus after Starvation and Re-feeding
Kim, Su Kyoung ; Shim, Na Young ; Jang, In Kwon ; Lee, Chu ; Kim, Yong Dae ; Kim, Bung Ki ; Kim, Jae Won ;
Korean Journal of Fisheries and Aquatic Sciences, volume 46, issue 6, 2013, Pages 793~800
DOI : 10.5657/KFAS.2013.0793
This study was conducted to determine the physiological and histological characteristics of starry flounder Platichthys stellatus juveniles to undergo a short/long starvation period and subsequent re-feeding with 2 weeks interval for 65 days. All findings from this study indicate the possibility of a very rapid recovery possibility of starry flounder after short starvation period for 2 or 4 weeks. The mean body weight after 2 and 4 weeks starvation were not significantly different after 65 days. However, the body weight of 6 and 8 weeks starved fishes showed significantly low value than 2 weeks starved fishes. All biomarkers, liver somatic index, RNA/DNA ratio and blood chemistry, in this study showed fast recovery possibility after re-feeding of starry flounder. During the starvation and recovery process, they showed distinct increasing and decreasing tendency. From 21-28 days after re-feeding, most biomarkers reached to their maximum value and thereafter decreased again in 2, 4 and 6 weeks starvation and re-feeding groups. It could be interpreted as a compensatory growth and strategical action against starvation.
Energy Budget of Spiny Lebbeid Shrimp Lebbeus groenlandicus Larvae
Kim, Won Gi ; Kwon, O-Nam ; Park, Kie-Young ;
Korean Journal of Fisheries and Aquatic Sciences, volume 46, issue 6, 2013, Pages 801~806
DOI : 10.5657/KFAS.2013.0801
Spiny lebbeid shrimp Lebbeus groenlandicus larvae were reared in the laboratory to estimate the energy budget from the zoeal to the post-larval stage. Energy expended by larvae on growth and respiration was determined from values for feeding, growth, molting, and metabolism. We calculated that 16.22 J were used for growth throughout all larval stages. Energy loss during molting was estimated as 1.03 J, and energy used for respiration was estimated as 1.31 J. Energy taken in by feeding was estimated as 77.16 J, while the sum of energies expended in excretion and egestion was 58.61 J. Larvae were estimated to assimilate 24.6% of ingested food as energy and to use ~85% of the assimilated energy for somatic growth. Gross growth efficiency (
) and net growth efficiency (
) were shown to be ~22% and 93%, respectively. Maintenance costs of respiration were estimated as ~9.7% of assimilated energy.
Energy Budgets of Pandalid Shrimp Pandalopsis japonica Larvae in the Different Larval Stages
Kim, Jin Gak ; Kwon, O-Nam ; Park, Kie-Young ;
Korean Journal of Fisheries and Aquatic Sciences, volume 46, issue 6, 2013, Pages 807~812
DOI : 10.5657/KFAS.2013.0807
The energy budget of the larvae of pandalid shrimp, Pandalopsis japonica, reared in the laboratory from zoea to post-larva was investigated. Energy used during the growth of the shrimp larvae was calculated daily for feeding, growth, molting, and metabolism. The total energy used was 16.2 J for the entire larval stage. Molting energy loss was estimated at a total 1.03 J. Energy used for respiration was estimated at a total of 1.85 J. The intake energy by feeding reached a total of 77.69 J. The total sum of energies used by excretion and egestion was 58.61 J. Larvae assimilated 24.57% of ingested food and used 84.91% for somatic growth. The gross growth efficiency (
) was 22.19% for the entire larval stage, and the net growth efficiency (
) was 90.31%. Maintenance costs were estimated at 9.69% of assimilated energy for the entire larval stage.
Effects of Water Temperature and Body Weight on the Filtration Rate of Sea Squirt Halocynthia roretzi
Jeong, Woo-Geon ; Cho, Sang-Man ;
Korean Journal of Fisheries and Aquatic Sciences, volume 46, issue 6, 2013, Pages 813~818
DOI : 10.5657/KFAS.2013.0813
In order to understand the co-culture impact of the sea squirt Halocynthia roretzi on the Pacific oyster Crassostrea gigas, we examined the filtration rate of the sea squirt in relation of water temperature (
) and body weight. The filtration rate increased in relation to body weight and water temperature, indicating a clear positive correlation with the two variables. Due to the clear positive correlation between filtration rates at each temperature groups for acceptable collinearity, each constants at regression equation was further analyzed for a unified model of filtration rate. Therefore the filtration rate of H. roretzi was estimated as: Fr (L/h/animal)=
for water temperature in the range of
. The estimated filtration rates of H. roretzi were higher than those of C. gigas in the winter season (water temperatures below
) in condition of equal body weight. Our results indicate that H. roretzi may have an advantage over C. gigas in food competition during the winter season when the two species are co-cultured.
Physiological Stress Responses in Black Seabream Acanthopagrus schlegelii Subjected to Acute Hypoxia
Min, Byung Hwa ; Park, Mi Seon ; Myeong, Jeong-In ; Hwang, Hyung Kyu ;
Korean Journal of Fisheries and Aquatic Sciences, volume 46, issue 6, 2013, Pages 819~826
DOI : 10.5657/KFAS.2013.0819
The black seabream Acanthopagrus schlegelii is an important species for aquaculture in Korea. There are, however, no reports on the physiological responses to hypoxia in this species. The objective of this study was to evaluate the effects of acute hypoxia on the physiological stress responses (plasma cortisol as the primary response, and plasma glucose, hematocrit (Ht), hemoglobin (Hb), sodium, chloride, osmolality, AST, ALT and total protein as the secondary responses) of the fish. The experimental fish were exposed to 0.5 ppm dissolved oxygen (DO) in the seawater via two methods (progressive stepwise decline (Exp. I), and direct decline (Exp. II)). A highly significant increase was detected in plasma cortisol levels due to the hypoxia treatments, and fish in Exp. I had hormone levels that were significantly higher than the fish in Exp. II. For plasma glucose, there was no significant difference between the Exp. I fish and the control fish, whereas Exp. II fish showed significantly higher plasma glucose levels than Exp. I fish and control fish. Ht values increased in both hypoxia treatments; however, Hb concentrations increased only in Exp. I. Although plasma chloride levels were unaffected by acute hypoxia, plasma sodium and osmolality levels increased in Exp. I. Progressive hypoxia (Exp. I fish) increased plasma AST, ALT and total protein. These results suggest that the value and direction of changes to the investigated parameters can be used to determine the resistance of black seabream to acute hypoxia.
The Effects of Environmental Factors on the Growth of Lithophyllum yessoense and Hildenbrandia rubra Sporelings in Laboratory Culture
Song, Ji Na ; Park, Seo Kyoung ; Oh, Ji Chul ; Yoo, Hyun Il ; Kim, Young Sik ; Choi, Han Gil ; Nam, Ki Wan ;
Korean Journal of Fisheries and Aquatic Sciences, volume 46, issue 6, 2013, Pages 827~834
DOI : 10.5657/KFAS.2013.0827
The effects of environmental factors, such as irradiance, daylength, salinity, and desiccation, on the growth of Lithophyllum yessoense and Hildenbrandia rubra sporelings were examined. Sporelings of each species were cultured with 10, 50, 80, 120,
for 14 days and their maximum growth occurred under
. Germlings of both species survived for 21 days in darkness, and even the L.yessoense germlings grew. In the salinity experiment, sporelings of each species survived for 7 days and died after 14 days under 20 and 25 psu, but the sporelings grew well under 34 psu. Physiological features of each species with respect to the evaluated daylengths (8, 12, 14 and 16 h) were slightly different, and maximal growth occurred at 16 h for L. yessoense and at 14 h for H. rubra sporelings. Mortality of the sporelings increased with the exposure period, but H. rubra was less tolerant to desiccation than L. yessoense. In conclusion, sporelings of the two species showed similar growth responses to various environmental factors with slightly different physiological features with respect to salinity, daylength, and desiccation. However, more ecological and physiological studies on slow-growing crustose algae are required to elucidate the expansion of barren ground around the coastal areas of Korea.
Maturation and Spawning of the Flathead Flounder Hippoglossoides dubius off the coast of Gangwon Province, East Sea of Korea
Choi, Young Min ; Yoon, Byoung Sun ; Park, Jeong-Ho ; Park, Kie Young ; Sohn, Myoung Ho ; Lee, Jae Bong ; Kim, Jae Won ;
Korean Journal of Fisheries and Aquatic Sciences, volume 46, issue 6, 2013, Pages 835~842
DOI : 10.5657/KFAS.2013.0835
Flathead flounder Hippoglossoides dubius is a commercially important fish in the coastal waters of Gangwon Province, which is its spawning ground and breeding habitat. A total of 1,669 gonads were sampled monthly from February 2011 to May 2013 to investigate ecological characteristics, such as variations in maturation and spawning by gonad index, visual maturity stage, histological observations and oocyte diameter. Males were numerically dominant over females in the fishing grounds year round. The spawning season was from January to April, and the peak was from February to March. Oocyte number as a measure of fecundity was between 27,372 and 915,209 eggs with a length range of 26.0-48.7 cm TL, while the largest oocyte grew to 0.9-1.4mm in egg diameter during its spawning season. The relationship between fecundity and total length was
. The smallest mature lengths of the females and males were 28.4 and 22.6 cm respectively, and the 50% mature lengths of females and males were 32.9, 26.9 cm respectively.
Feeding Habits of Lycodes tanakae in the Coastal Waters of the middle East Sea, Korea
Choi, Young Min ; Yoon, Byoung Sun ; Kim, Hyo Seon ; Park, Jeong Ho ; Park, Kie Young ; Lee, Jae Bong ; Yang, Jae Hyeong ; Sohn, Myoung Ho ;
Korean Journal of Fisheries and Aquatic Sciences, volume 46, issue 6, 2013, Pages 843~850
DOI : 10.5657/KFAS.2013.0843
The feeding habits of Lycodes tanakae Eelpout were studied with 722 specimens collected from March 2011 to December 2012 in the coastal waters of the middle East Sea. The main prey of L. tanakae were fish, molluscs and arthropods. Nevertheless annelida, echinodermata and others were found in small amounts in the stomach contents. The L. tanakae stomach was empty of contents in 50.9% of specimens. While smaller size specimens of L. tanakae (less than 40 cm) fed mainly on euphausiids and amphipods, the larger specimens (more than 40 cm) fed on the fish Allolepis hollandi and Icelus cataphractus, and the molluscs Berryteuthis magister and Watasenia scintillans. The main prey items of L. tanakae varied seasonally. The fish Lycodes nakamurai was the dominat prey from November to January during its spawning season. Euphausiids and amphipods of the arthropods were the dominant prey from February to April. The molluscs Berryteuthis magister and Watasenia scintillans were the dominant prey from May to September. The diversity index (H') of diets showed variations by length class and month; the highest values were 2.61 in the length class of 51-55 cm, and the monthly highest were 2.68 in September with 23 species and 2.65 in November with 18 species. The highest dominance index (D') of diets was 0.57 in the length class of 31-35 cm, and the monthly highest was 0.71 in February. Cluster analysis divided prey groups into four groups by length class and three groups by monthly prey items. The gonad index gradually increased during the process of maturation while, contrary, stomach content index decreased during this period.
Catch Distribution of Ocean Sunfish Mola mola off Korean Waters
Lee, Dong-Woo ; Choi, Jung-Hwa ; Choi, Kwang-Ho ;
Korean Journal of Fisheries and Aquatic Sciences, volume 46, issue 6, 2013, Pages 851~855
DOI : 10.5657/KFAS.2013.0851
To determine the status of sunfish fishery, fishing places, body size, weight, etc. were investigated from 2010 to 2012 in Busan Cooperative Fish Market. Most of the sunfish were caught by large purse seine around Jeju island, and the fishing ground of sunfish were reached from Heuksando in the southern Yellow Sea to Guryongpo in the southern East Sea. The range of total length (TL) of the sunfish caught by purse seine was 55-271 cm, and the estimated length-weight relationship was
. From the relationship, the weight of 50 cm in total length was estimated to be ca. 4 kg, TL 100 cm was ca 46 kg, TL 200 cm was ca 478 kg, and TL 271 cm was estimated to be 1,336 kg.
Occurrence of Architeuthis sp. and Regalecus russellii in the East Sea, Korea
Lee, Hae Won ; Yang, Jae Hyung ; Sohn, Myoung Ho ; Lee, Jae Bong ; Chun, Yong Yul ; Hwang, Kang Seok ; Lee, Dong Woo ;
Korean Journal of Fisheries and Aquatic Sciences, volume 46, issue 6, 2013, Pages 856~861
DOI : 10.5657/KFAS.2013.0856
The first occurrence of a giant squid, Architeuthis sp. (one specimen), and the oarfish, Regalecus russellii (two specimens) in the East Sea were reported based on specimens collected in January and February 2010. The giant squid (Architeuthis sp.) stranded at Pohang in Jan. 2010 was female, 175 cm in mantle length (ML), 506 cm in tentacle length (TL), and 33.9% FL/ML, it contained common squid beaks. Both stranded oarfish (Regalecus russellii) at Uljin (Jan. 2010) and Yeongdeok (Feb. 2010) were male, with total weigths (TW) of 18,506 and 21,703 g and total lengths (TL) of 3,850 and 3,670 mm, respectively. The stomach of the first was empty, while that of the second was filled with euphausiids. In the East Sea, giant squid have been stranded 14 times in five areas, while 17 oarfish have been stranded in nine areas. Since 1990, the two species have been found most often at Pohang.
The Effects of Elevated Carbon Dioxide in Seawater on the Early Life Stages of Black Sea Bream Acanthopagrus schlegelii
Shim, JeongHee ; Kim, Kyungsu ; Kim, Suam ;
Korean Journal of Fisheries and Aquatic Sciences, volume 46, issue 6, 2013, Pages 862~867
DOI : 10.5657/KFAS.2013.0862
Since the industrial revolution, seawater has increased in temperature and acidity due to the increase in anthropogenic carbon dioxide in the atmosphere. To understand the effect of elevated
on the early life stages of fish, we reared fertilized eggs of black sea bream Acanthopagrus schlegelii under three
concentrations (400, 850 and 1550 ppm) for 3 weeks. The standard length and wet weight of black sea bream larvae declined with enhanced
concentration in the rearing water (P<0.05). However, chemical analysis using ICP-OES on internal tissues of black sea bream larvae indicated that the whole-body calcium concentration increased with
concentration in the rearing water. These conflicting results suggest that future experiments should examine the acid-base balance to investigate the formation of bone and otolith during larval growth.
Effects of Meteorological and Oceanographic Properties on Variability of Laver Production at Nakdong River Estuary, South Coast of Korea
Kwon, Jung-No ; Shim, JeongHee ; Lee, Sang Yong ; Cho, Jin Dae ;
Korean Journal of Fisheries and Aquatic Sciences, volume 46, issue 6, 2013, Pages 868~877
DOI : 10.5657/KFAS.2013.0868
To understand the effects of marine environmental and meteorological parameters on laver Porphyra yezoensis production at Nakdong River Estuary, we analyzed marine environmental (water temperature, salinity, nutrients, etc.) and meteorological properties (air temperature, wind speed, precipitation, sunshine hours) with yearly and monthly variations in laver production over 10 years (2003-2013). Air and water temperature, wind speed, sunshine hours and precipitation were major factors affecting yearly variability in laver production at the Nakdong River Estuary. Lower air and water temperatures together with higher levels of nutrients and sunshine and stronger wind speeds resulted in higher laver harvests. Salinity and nitrogen did not show clear correlations with laver production, mainly due to the plentiful supply of nitrogen from river discharge and the low frequency of environmental measurements, which resulted in low statistical confidence. However, environmental factors affecting monthly laver production were related to the life cycle (culturing stage) of Porphyra yezoensis and were somewhat different from factors affecting annual laver production. In November, a young laver needs lower water temperatures for rapid growth, while a mature laver needs much stronger winds and more sunshine, as well as lower temperatures for massive production and effective photosynthesis, mostly in December and January. However, in spring (March), more stable environments with fewer fluctuations in air temperature are needed to sustain the production of newly deployed culture-nets (
time culture). These results indicate that rapid changes in weather and marine environments caused by global climate change will negatively affect laver production and, thus, to sustain the yield of and predict future variability in laver production at the Nakdong River estuary, environmental variation around laver culturing farms needs to be monitored with high resolution in space and time.
Seasonal Variation in Biomass and Community Structure of Intertidal Seaweeds at Heuksando and Hongdo, Southwestern Coast of Korea
Oh, Ji Chul ; Park, Seo Kyoung ; Choi, Han Gil ; Nam, Ki Wan ;
Korean Journal of Fisheries and Aquatic Sciences, volume 46, issue 6, 2013, Pages 878~885
DOI : 10.5657/KFAS.2013.0878
Seasonal variation in marine macroalgal community structure was examined at the intertidal zones of Heuksando and Hongdo, Shinan, Korea, from July 2008 to May 2009. In total, 86 macroalgal species were identified, including 12 green, 19 brown, and 55 red algae; 67 species at Heuksando and 70 species at Hongdo, were observed. Annual seaweed biomass was 252.44 g dry
at Heuksando and 217.67 g dry
at Hongdo. The dominant seaweed in importance value (IV > 15) differed between the sites: Sargassum thunbergii at Heuksando and Corallina pilulifera at Hongdo. The vertical distribution pattern of seaweeds from the upper to lower intertidal zones at Heuksando was Gloiopeltis spp., Ulva spp. - S. thunbergii, S. fusiforme, Hildenbrandia rubra - S. thunbergii, C. pilulifera. On the rocky shore of Hongdo, seaweed zonation was distinct: Porphyra yezoensis, Gloiopeltis spp., Ulva spp. - C. pilulifera, S. fusiforme, Myelophycus simplex - Chondrus ocellatus, C. pilulifera, and Carpopeltis affinis. Annual seaweed coverage, richness index (R), evenness index (J'), and diversity index (H') values were greater at Hongdo (41.35%, 12.82, 0.59, and 2.50 respectively) than at Heuksando (31.54%, 11.93, 0.44, and 1.87 respectively), which may indicate that the seaweed community at Hongdo is more stable relative to the one at Heuksando.
Substrate Characteristics of Sea Cucumber Stichopus japonicus Habitats in the West Coast of Korea
Park, Kwang-Jae ; Ryu, Sang-Ock ; Baek, Young-Sook ; Kim, Yeun-Seol ; Kang, Hee-Woong ; Han, Hyon-Sob ;
Korean Journal of Fisheries and Aquatic Sciences, volume 46, issue 6, 2013, Pages 886~891
DOI : 10.5657/KFAS.2013.0886
We analyzed surface sediments to explain the substrate characteristics of sea cucumber Stichopus japonicus habitat. The analyses included grain-size determination, water content (WC), loss on ignition (IL), chemical oxygen demand (COD), and acid volatile sulfide (AVS) content. We obtained data on sea cucumber density, weight, and length at each station in a marine farming area in the middle of Korea's Taean coast on the West (Yellow) Sea in May, 2012. The apparent density of S. japonicus was high in coarse and bimodal sediments, whereas it was low in fine and unimodal sediments. The mass of S. japonicus was greater in fine than in coarse sediments, showing a different trend from sea cucumber density. The values for WC, IL, COD, and AVS in surface sediments were higher in areas with high densities of S. japonicus than in areas with low sea cucumber densities. In particular, the concentration of AVS was much higher than the value proposed in Japanese criteria for areas with high S. japonicus density.
Status of the Cetacean Bycatch near Korean Waters
Kim, Doo Nam ; Sohn, Hawsun ; An, Yong-Rock ; Park, Kyum Joon ; Kim, Hyun Woo ; Ahn, So Eon ; An, Du Hae ;
Korean Journal of Fisheries and Aquatic Sciences, volume 46, issue 6, 2013, Pages 892~900
DOI : 10.5657/KFAS.2013.0892
In 2011, the system for conserving and managing cetacean resources in Korea changed. The status of the cetacean bycatch was analyzed using a distribution certificate that was issued by the coast guard. During 2011.2012, 12 species were bycatch in Korean waters: three species of baleen whale and nine species of dolphin. The finless porpoise (Neophocaena phocaenoides) was the dominant species, followed by the common dolphin (Delphinus delphis), harbor porpoise (Phocoena phocoena), and Pacific white-sided dolphin (Lagenorhynchus obliquidens). Among the baleen whales, the common minke whale (Balaenoptera bonaerensis) was first and Bryde's (Balaenoptera edeni) and humpback (Megaptera novaeangliae) whales appeared in the Korea Strait and East Sea, respectively. Among the dolphins, the finless porpoise ranked first in the Yellow Sea. The common dolphin, Pacific white-sided dolphin, and harbor porpoise were more frequent in the East Sea than in other waters. The cetacean bycatch was caused mainly by pots, set nets, gill nets, and stow nets. Among the three species of baleen whale, the common minke whale was caught by pots and set nets, and comprised over 68.9% of the total bycatch in 2011 and 56.2% in 2012. Comparing the bycatch caused by fishing gears by area in 2011 and 2012, 97.9% and 99.6%, respectively, of the finless porpoise bycatch in the Yellow Sea was by stow nets. In the Korea Strait, trawl bycatch comprised 67.3% in 2011 and 73.0% in 2012, followed by gill nets, set nets, and pots targeting finless porpoise and common minke whales. In the East Sea, gill nets were responsible for 46.7% in 2011 and 61.2% in 2012, followed by set nets and pots.
Availability of the lacZ gene as a Reporter Gene for Production of Transgenic Artemia franciscana
Jung, Hyo Sun ; Kim, Dong Soo ;
Korean Journal of Fisheries and Aquatic Sciences, volume 46, issue 6, 2013, Pages 901~906
DOI : 10.5657/KFAS.2013.0901
We examined the availability of the lacZ gene (
-galactosidase gene) as a reporter of foreign gene transfer in the cysts of Artemia franciscana (A. franciscana) to conduct a risk assessment of living genetically modified organisms (LMOs) in the marine ecosystem. The LacZ gene was transferred to decapsulated cysts by particle bombardment, and its insertion and expression were assessed by means of polymerase chain reaction (PCR) and X-gal staining. X-gal staining indicated lacZ expression in all A. franciscana examined (including the control group), which exhibited not only negative but also positive PCR amplification. Endogenous
-galactosidase is highly active in the whole body of A. franciscana during all stages of the life cycle. Thus, the lacZ gene is unsuitable as a reporter for foreign gene transfer in A. franciscana cysts, because it is difficult to discriminate between exogenous and endogenous
Comparison of Community Structure of Fish Larvae in the Northern East China Sea in Normal and El Niño/La Niña Periods
Yoo, Joon-Taek ; Choi, Jung-Hwa ; Kim, Jin-Yeong ; Kim, Jong-Bin ; Choi, Kwang-Ho ;
Korean Journal of Fisheries and Aquatic Sciences, volume 46, issue 6, 2013, Pages 907~916
DOI : 10.5657/KFAS.2013.0907
The aim of this study was to compare community structure of larval fish species in the northern East China Sea during normal meteorological conditions in autumn 2009, during the El Ni
o period in 2009-2010, and during the La Nina period in 2010. Fifty taxa were recorded during the study period; the most dominant species were Benthosema pterotum and Gobiidae spp. In October 2008 during the normal period, warm water from the Tsushima Warm Current (TWC) intruded more into the surface and middle layers, and cold water affected by the Yellow Sea Cold Water (YSCW) intruded into the bottom layer. In October 2009 during the El Ni
o period, intrusion of the China Coastal Water (CCW), which has low salinity (<32.2 psu), was more apparent than intrusion of the TWC or YSCW. In October 2010 during the La Nina period, intrusion of the TWC and CCW was relatively weak, resulting in the lowest temperature and highest salinity observed during the study period in the eastern part of the study area. Hierarchical cluster, one-way ANOSIM (analysis of similarities), and SIMPER (similarity-percentages procedure) analyses provided two main results. First, the abundance of the most dominant larval fish species in autumn of the normal period was greater than that in autumn of the El Ni
o/La Nina periods, resulting in a significant difference in ichthyoplankton community structure between the periods. The abundance of Benthosema pterotum increased in the normal period, possibly influenced by the intrusion of cold water from the YSCW; the abundance of species residing in Korean waters (e.g., Gobiidae spp.) probably decreased during the El Ni
o/La Nina periods. The second finding was that the abundance of subtropical larval fish in autumn of the normal period was generally larger than that during autumn of the El Ni
o/La Nina periods. This could have been induced by the stronger intrusion of warm water from the TWC during the normal period. Although differences in oceanographic conditions between El Ni
o and La Nina periods were observed, the differences in ichthyoplankton community structure between the two periods were not significant.
Changes of Fishing Ground of the Large Pair Trawl Fishery off Korean Waters
Lee, Dong-Woo ; Choi, Kwang-Ho ; Kang, Sukyung ;
Korean Journal of Fisheries and Aquatic Sciences, volume 46, issue 6, 2013, Pages 917~922
DOI : 10.5657/KFAS.2013.0917
Changes in fishing ground of the large pair trawler were investigated by year, month and species off Korean waters. We used catch data by sea-block lat.
) of the National Fisheries Research and Development Institute (NFRDI) and monthly fishing production statistics of Korean statistic information service from 1990 to 2007. In the 1990s, the demersal fish like Larimichthys polyactis, Collichthys sp, Portunus trituberculatus and Muraenesox cinereus were the dominant species, and in the 2000s, they were changed from demersal fish into pelagic fish like Scomberomorus niphonius, Scomber japonicus, Engraulis japonicus and Todarodes pacificus. Species composition of catch showed temporal variation by cluster analysis deviding into 4 period, 1990-1994, 1995-2000, 2001-2003 and 2004-2007. Fishing ground in the 2000s was decreased up to 2/3 in the 1990s, while the density of catch in the fishing ground in 2000s was higher than the 1990s.
Tolerance and Histological Responses to Formalin of Black Seabream Acanthopagrus schlegelii Juveniles
Myeong, Jeong-In ; Min, Byung Hwa ; Park, Mi Seon ; Hwang, Hyung Kyu ; Do, Jeung-Wan ; Jeoung, Kyung Il ; Chang, Young Jin ; Jeong, Dal Sang ;
Korean Journal of Fisheries and Aquatic Sciences, volume 46, issue 6, 2013, Pages 923~929
DOI : 10.5657/KFAS.2013.0923
Black seabream juveniles Acanthopagrus schlegelii held at
were exposed to formalin at concentrations of 50 to 400 ppm, and tolerance values were determined by calculating median lethal concentration values (LC50) through probit analysis. The 12-, 24, 48, 72- and 96-h LC50 values for formalin were 297, 233, 171, 162 and 157 ppm, respectively. The histological effects of formalin on gill and liver tissues in this fish were determined. No histological effects were observed in the control group. The intensity of cell damage increased with the concentration of, and duration of exposure to, formalin. Hyperplasia, separation and epithelial necrosis, epithelial lifting, lamellar synechiae and collapsed lamellae were observed in gill tissues exposed to formalin. Hepatic lesions in liver tissues of fishes exposed to formalin were characterized by cloudy swelling of hepatocytes, necrosis, cytoplasmic vacuolization, deposition of pigments, spongiosis hepatis, nuclear hypertrophy, dilation of sinusoids and bile stagnation. The LC50 values and histological results obtained in this study will aid in designing treatment regimens to minimize toxic side effects and increase efficacy.
Evaluation of Organic Matter and Trace Metal Contamination in Surface Sediments around the Geum River Estuary using Sediment Quality Guidelines
Hwang, Dong-Woon ; Lee, In-Seok ; Choi, Minkyu ; Kim, Sook-Yang ; Choi, Hee-Gu ;
Korean Journal of Fisheries and Aquatic Sciences, volume 46, issue 6, 2013, Pages 930~940
DOI : 10.5657/KFAS.2013.0930
We evaluated contamination with organic matter and trace metals by analyzing grain size, ignition loss (IL), chemical oxygen demand (COD), acid volatile sulfide (AVS), and trace metals (Al, Fe, Cu, Pb, Zn, Cd, Ni, Cr, Mn, Hg, and As) in surface sediments at 28 stations around the Geum River estuary in July 2008. The surface sediments in the estuary were mainly composed of coarse sediment (sand and muddy sand), with mean grain size (Mz) ranging between
. The high concentrations of IL, COD, and trace metals were mainly found at stations in front of the Gusan outer port and industrial complex, and near the Seocheon coast with relatively fine sediments. In addition, the concentrations of IL and all trace metals, except Pb and As, showed good positive correlations with Mz, indicating that the concentrations of organic matter and trace metals were mainly dependent on sediment grain size. The concentrations of COD, AVS, and trace metals in most sediments did not exceed the sediment quality guideline (SQGs). Although the sediments in the study region are not polluted with organic matter and trace metals, there are many point sources of pollutants, such as Gusan port and industrial complex, Janghang refinery, and a thermoelectric power plant around the Geum River estuary. Thus, the management of coastal environments through periodic monitoring of organic matter and trace metals is required in the future.
Analysis of Long-term Oceanic Data for the Prediction of Undaria pinnatifida Aquaculture Production off the Coast of Busan
Han, In-Seong ; Suh, Young-Sang ; Lee, Joon-Soo ;
Korean Journal of Fisheries and Aquatic Sciences, volume 46, issue 6, 2013, Pages 941~947
DOI : 10.5657/KFAS.2013.0941
To understand the relationship between various oceanographic factors and seaweed production, we examined the annual accumulated aquaculture production of Undaria pinnatifida with respect to water temperature, salinity, dissolved oxygen, current patterns and nutrients over 21 years (1990-2010) (this date range does not add up to over 21 years) along the coast of Busan, Korea. According to the results of the cross-correlation function, annual production of U. pinnatifida was closely related to the following conditions: low water temperature, low salinity, strong Tsushima Warm Current, and high concentrations of dissolved oxygen and nutrients. In this study, we also considered the Index of Oceanographic factors for U. pinnatifida (IOU) by computation of a simple equation. This index will be used for the prediction of U. pinnatifida aquaculture production off the coast of Busan.
Seasonal Variation in the Species Composition of Fish Assemblages in the Coastal Waters off Gadeok-do, South Sea, Korea
Jeong, Jae Mook ; Park, Joo Myun ; Huh, Sung Hoi ; Ye, Sang Jin ; Kim, Hyeon Ji ; Baeck, Gun Wook ;
Korean Journal of Fisheries and Aquatic Sciences, volume 46, issue 6, 2013, Pages 948~956
DOI : 10.5657/KFAS.2013.0948
Seasonal variations in species composition and abundance of the fish assemblages in the coastal waters off Gadeok-do were determined using monthly sample collection by a small otter trawl in 2010-2011. Of a total of 65 fishes collected, the dominant species were Leiognathus nuchalis, Clupea pallasii, Thryssa kammalensis, Engraulis japonicus, Repomucenus valenciennei, Sillago japonica, Trachurus japonicus, Pennahia argentatus, Okamejei kenojei, Cynoglossus joyneri, Pholis fangi, Pleuronectes yokohamae, and Zoarces gillii. These 13 fishes accounted for 92.8% of the total number of individuals collected. The number of fish species, number of individuals, biomass, and species diversity indices fluctuated with the seasons. The peak number of fishes occurred in April, whereas the biomass of fishes was highest in August. The numbers and biomass of fishes were lower in February corresponding with the low temperatures, and diversity indices were lower in January than in any other month.
Buoyancy and Vertical Distribution of Mackerel Scomber japonicus Eggs in Korean Waters
Jung, Kyung-Mi ; Kang, Sukyung ; Cha, Hyung Kee ; Choi, Kwang Ho ; Myksvoll, Mari S. ;
Korean Journal of Fisheries and Aquatic Sciences, volume 46, issue 6, 2013, Pages 957~965
DOI : 10.5657/KFAS.2013.0957
This study simulated the egg vertical distribution of mackerel Scomber japonicus in Korean waters using general numerical models. All eggs were spawned naturally by raising broodfishes (May-June 2013), and the egg specific gravity was measured by a density-gradient column. CTD surveys provided environmental data (e.g., temperature and salinity) in May near Jeju Island, Korea. The egg specific gravity during the early stages ranged from 1.0203-1.0211. In general, the fertilized eggs showed a gradual decline in egg specific gravity until full development of the main organs, with a sudden increase just before hatching. Modeled egg vertical distributions were influenced more by wind speed than by egg buoyancy and vertical structure of the sea water. During calm and normal wind speeds, the eggs were distributed from the surface to 25-m depths. Under strong wind conditions (three times higher than the normal speed), the egg concentration on the surface decreased, and the egg distributional depth was deeper (~50 m).
Feasibility of Aerial Surveys of Finless Porpoise Neophocaena asiaeorientalis off the West Coast of Korea
Park, Kyum Joon ; Sohn, Hawsun ; Kim, Yeong Hye ; Kim, Doo Nam ; Kim, Hyun Woo ; An, Du Hae ; An, Yong-Rock ;
Korean Journal of Fisheries and Aquatic Sciences, volume 46, issue 6, 2013, Pages 966~969
DOI : 10.5657/KFAS.2013.0966
Vessel-based sighting surveys for cetaceans have been conducted in Korean waters since 2000. The supporting data estimate the abundance of finless porpoises along the west coast of Korea; however, they are insufficient because of the coverage and frequency of the surveys. A preliminary aerial survey was conducted in 2011, and the results were assessed with respect to a sighting survey operated by a research vessel in order to compare effectiveness and potentiality. A total of 110.00 nautical miles of effective efforts were made with three sightings under Beaufort scale 4 in the aerial survey, while the vessel-operated survey covered 403.38 nautical miles over 7 days without any sightings under Beaufort scale 4. The standard deviation of the altitude in this survey was 22.7 m, which was significantly higher than that of the referenced study of 4.3 m.
Relative Growth of Microstomus achne (Pleuronectidae, PISCES) during Early Life Stage
Byun, Soon-Gyu ; Kang, Chung-Bae ; Han, Kyeong-Ho ; Kim, Jin-Koo ;
Korean Journal of Fisheries and Aquatic Sciences, volume 46, issue 6, 2013, Pages 970~972
DOI : 10.5657/KFAS.2013.0970
We examined the relative growth of Microstomus achne during early life stages of laboratory-reared larvae and juveniles. Turning points in the relative growth of preanal length and upper jaw length against total length occurred during the settlement period (11.12-19.91 mm in total length). However, turning points in the relative growth of head length and eye diameter, as compared to total length, occurred during metamorphosis (17.57-22.47 mm in total length). Our results suggest that Microstomus achne concentrates its energy on the feeding apparatus (jaw) and digestive organs (intestine) rather than sensory or neural organs (eye, head) during early larval stage growth.
Vertical Distribution and Feeding Ecology of the Mirror Dory Zenopsis nebulosa in the Southern Sea of Korea
Kim, Hye Rim ; Kim, Jung Yun ; Kim, Hee Yong ; Choi, Gwang Ho ; Choi, Jung Hwa ;
Korean Journal of Fisheries and Aquatic Sciences, volume 46, issue 6, 2013, Pages 973~976
DOI : 10.5657/KFAS.2013.0973
We observed the vertical distribution and feeding ecology of the Mirror dory, Zenopsis nebulosa, in the Southern Sea of Korea from 2009 to 2013 using an otter trawl. The total length of captured individuals ranged from 11 to 48 cm. Individuals captured at greater depths were significantly larger than those from shallower sites. Fish abundance was significantly related to depth and temperature. We found that 89% of the total catch was obtained at depths between 80 and 140 meters. Prey organisms, including fish, crustaceans, and cephalopods, were found in Z. nebulosa stomachs. Fishes were the main prey items for all size groups. Cephalopods were consumed by individuals > 25 cm in length. Our findings suggested that the vertical distribution of Z. nebulosa varied with depth and temperature, and that the fish are carnivores.