• Korean Journal of Fisheries and Aquatic Sciences
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• v.14 no.1
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• pp.43-46
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• 1981

The ratio of the eatable flesh taken from the filefish and its chemical components were investigated from March 1980 to February 1981 and the results are as follows :1. The ratio of the eatable flesh taken from the fish was low during March to June and high during July to December. 2. The moisture content was $81.4-82.0\%$ during March to June, $77.5-80.1\%$ during July to December and $79.4-81.4\%$ during January to February. 3. The protein content was $15.4-15.7\%$ during March to June, $17.0-19.9\%$ during July to December and $16.1-17.0\%$ during January to February. 4. The Lipid content was $0.31-0.41\%$ during March to January, $0.46-0.84\%$ during July to January and $0.43\%$ during February. 5. The carbohydrate content was $0.3-0.4\%$ during March to July, $0.5-0.7\%$ during August to January and $0.3\%$ during February. In conclusion, the ratios of the eatable flesh taken from the filefish and its protein content were highest during July to December in one year.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.17 no.6
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• pp.523-528
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• 1984

The small filefish, Rudarius ercodes, generally spawning from mid May to early October in the natural habitat, was exposed to various photoperiod and temperature regimes. These environmental effects on the gonad activity, regression and recrudescence were experimentally investigated based on the mechanism of reproductive cycle. Spawning season was initiated in the early spring with the gonad activated by long photoperiod(13L) and stimulated by compensatory temperature rising. Even when the gonad activated readily at the above critical daylength (12L to 13L)was kept back at the below if, it went on maturing. At the end of spawning period (mid September), since the shortening of daylength (12L) resulted in the gonad regression regardless of temperature, the short daylength might be related to the termination of spawning in situ. When the regressive gonad at the post spawning period was treated by the above 13L: $20^{\circ}C$ condition, it could recrudesce and bring forth even spawning. From this fact, the feasible control of annual reproductive cycle of small filefish was recognized. But even in the long daylength, the temperature above $28^{\circ}C$ was preventive of gonad maturation.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.28 no.4
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• pp.428-434
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• 1995

The purpose of this study is to develop a sanitary aquarium for the safety slices of raw fish by using U.V. light. Water re-circulating system was composed of two tanks. One of the tanks $(90\times45\times45cm\;in\;size),$ was used for rearing fish and the other $(90\times45\times45cm\;in\;size),$ with 37 pieces of corrugated plastic plates was used for the growth of Nitrosomonas and Nitrobacter to remove ammonia from the water. Consequently, bactericidal effects of U.V. light were examined under the controlled condition of water with flow rate 730m1/sec (water flow thickness: 10mm), the width 41cm of water flow route, and the distance 4.75cm from the lamp to its water bottom, and U.V. light 75W (5 lamps). The water of the aquarium tank will be theroetically circulated 1 cycle per 18 min. In these conditions the bactericidal effect was $85\%$ just after passing through U,V. light and 3 log cycle in aquarium tank water. The count of Vibrio parahaemolyticus just after irradiation was decreased by about over than 3 log cycle. Under the irradiation for 72 hours, viable cell counts in both skin and gill of fish reared were decreased into about 2 log cycle, but there was no significant decrease in viscera. When the temperature of the tank was controlled at about $20-23^{\circ}C$ under the same condition, viable cell counts were reduced about 2 log cycle, and fecal coliforms were reduced about 1 log rycle and 3 log cycle in Crassostrea gigas and Mytilus edulis, respectively.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.15 no.3
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• pp.185-190
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• 1982

In utilization of small size red muscled fishes like mackerel, sardine, and filefish, mechanical dressing is usually required. The removal of dark muscle is also necessary to improve qualify of the product, which could hardly be done by mechanical process. As a method of separating dark muscle, specific gravity method using sugar solution was investigated in this study. And the effects of the level of specific gravity, the size and density of meat particles, and stability of meat particle float on the separation of dark muscle were discussed. From the results, effective specific gravity, in case of sucrose solution, ranged 1.067 to 1.072 for mackerel, 1.062 to 1.070 for sardine, and 1.072 to 1.077 for filefish, respectively. The maximum separation of more than $90\%$ was obtained at specific gravity of 1.075, 1.070, and 1.075 in cases of mackerel, sardine and filefish, respectively. The size of meat particles which were ground with 0.2cm orifice plate was adequate to yield $90\%$ separation or above. The meat particle float in the glucose solution began to precipitate within 5 minutes after separation while 25 minutes in case of sucrose solution. Lipids were also fairly removed by the dark muscle separation process.

• Development and Reproduction
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• v.11 no.3
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• pp.227-233
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• 2007

The milt properties of filefish(Thamnaconus modestus) included physical properties of sperm and biochemical properties of seminal plasma. The physical properties of milt were $0.3{\pm}0.1\;mL{\cdot}fish^{-1}$ in sperm volume, $2.6{\pm}0.1{\times}10^7\;spermatozoa{\cdotg}mL^{-1}$ in sperm concentration and $73.3{\pm}6.7$ in spermatocrit. The biochemical properties of seminal plasma contained $9.8{\pm}0.9\;mmol{\cdot}L^{-1}$ potassium, $164.0{\pm}4.0\;mmol{\cdot}L^{-1}$ sodium, $151.0{\pm}1.2\;mmol{\cdot}L^{-1}$ chloride, $14.9{\pm}0.6\;mg{\cdot}dL^{-1}$ calcium, $7.2{\pm}0.1\;mg{\cdot}dL^{-1}$ magnesium, $1.0\;mg{\cdot}dL^{-1}$ glucose, $0.1\;g{\cdot}dL^{-1}$ total protein and $1.0\;mg{\cdot}dL^{-1}$ total lipid. The osmolality and pH of seminal plasma were $322.8{\pm}2.8\;mOsmol{\cdot}kg^{-1}$ and $7.7{\pm}0.1$, respectively. The spermatozoon of filefish consisted of three parts: head without acrosome, mid-piece with five mitochondria and flagellum with "9+2" pattern. The head of spermatozoon in longitudinal section was horseshoe-shaped, and $1.3{\sim}1.6\;{\mu}m$ long and $1.0{\sim}1.3\;{\mu}m$ wide.

• Korean Journal of Food Science and Technology
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• v.14 no.1
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• pp.36-42
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• 1982

An investigation on optimum processing conditions for meaty textured fish protein concentrate (MT-FPC) was carried out with the fish meat of filefish, Navodon modestus, and sandfish. Arctoscopus japonicus. The processing conditions were determined by the lipid content and the rehydration capacity of MT-FPC. The optimum pH and sodium chloride content of fish meat were 8.0 and 1.0%, respectively. The most effective soaking conditions were: soaking time in chilled ethanol was 15 min for both filefish and sandfish; amount of chilled ethanol, 3 volumes and 4 volumes for filefish and sandfish, respectively; temperature of chilled ethanol, $25 ^{\circ}C$ for both filefish and sandfish; soaking time in boiling ethanol, 15 and 25 min for filefish and sandfish, respectively; amount of boiling ethanol, 2 and 4 volumes for filefish and sandfish, respectively; and number of snaking in boiling ethanol, 2 and 4 times for filefish and sandfish, respectively. Yields of the product to the minced meat weight, the contents of protein and lipid in MT-FPC prepared from filefish were 13.7%, 84.5% and 0.2%, and those from sandfish were 12.5%, 84.2% and 1.1%, respectively.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.14 no.4
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• pp.189-193
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• 1981

An apparatus for continuous measurements of sorption isotherm of dried food was manufactured to shorten the time required for equilibration. The apparatus was so designed that the temperature, air velocity and relative humidity in the experimental chamber could be controlled. The use of dynamic stream of conditioned air with a velocity of 0.2m/sec, instead of static atmosphere, allowed a faster equilibration of dried filefish muscle at $25^{\circ}C$. The mean time necessary for the equilibration of dried filefish muscle at the water activity of a given state to a higher water activity was about 45 hours. The monolayer moisture content of dried filefish muscle calculated from BET-equation was 0.092 kg water /kg dry matter at $25^{\circ}C$.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.5
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• pp.707-712
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• 1998

Seasonal variation in the proximate composition, cholesterol (CHOL) and $\alpha$-tocopherol ($\alpha$-Toc) content of 12 spices of fish muscle, which caught off Tongyeong coast of the Southern Sea (Nam-Hae) from Mar. 1995 to Feb. 1996, was studied. Lipid and moisture content showed remarkable seasonal variation and there were a negative correlation between the both (r= -0,85, p<0.001), while protein and ash content unchanged almost through the sampling period. The lipid content of anchovy, hickoryshad, black sea bream, finespotted flounder sea eel, bastard, and file fish was high in Dec. Oct. Nov. Jan. Jan. Nov, respectively, and low in the season corresponding to their spawning period. However, in case of striped mullet, yellow tail, mackerel, rock fish and red sea bream, there was no correlation between their lipid content and spawning period, and thus these fishes fore considered to be affected more by water temperature and the content of their diet. CHOL content increased In :he season containing a high level of lipid, whereas $\alpha$-Toc content unchanged almost through the sampling period.

• Korean Journal of Ichthyology
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• v.9 no.1
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• pp.48-60
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• 1997

The species composition and seasonal variations of fish community in the Zostera marina belt at the coastal water off Hamduck, northern part of Cheju Island, were analyzed based on day and night samples collected by a small beam trawl from May 1993 to May 1994. The dominant species among the 58 fish species in 35 family were tubesnout, Aulichthys japonicus, gobie, Pterogobius zonoleucus, filefish, Rudarius ercodes, pipefish, Syngnathus schlegeli and sea catfish, Plotosus lineatus. These species comprised 86.1% in the number of individuals and 62% in biomass. The number of individuals and biomass were high between October and December, and low between January and April. About 90% of fishes were noncommercial and small-sized fishes, less than 14cm in total length. The larvae and juvenile fishes were collected in the study area throughout the year. The recruitments of dominant species were related to the seasonal variations of Z. marina utilized as a shelter or feeding ground. A japonicus, P. zonoleucus, Zoarchias glaber and Hexagrammos agrammus recruited between January and June, and R. ercodes, S. schlegeli, P. lineatus and Petroscirtes breviceps between July and December.

• Korean Journal of Ichthyology
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• v.30 no.2
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• pp.107-113
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• 2018

To observe species composition and seasonal variation of fish in the coastal area, monthly underwater visual census were conducted from October 2016 to September 2017 in Tongyeong, Korea. A total of 5,358 individuals belong to 45 species were observed during the study. Perciforme fish were the most dominant (29 species), followed by Scorpaeniformes (8 species), Tetraodontiformes (3 species). The most dominant species is Sebastes inermis (19.2%), and followed by Rudarius ercodes (18.5%). Thirty three species with the highest abundance were observed in October 2016 and only 4 species were observed in February 2017. Among three subtropical fishes, such as Chaetodontoplus septentrionalis, Labroides dimidiatus, and Ostracion cubicus, the latter 2 species were firstly observed in the southern coast of Korea. Compared with the previous studies using conventional tools such as beam trawl and seine net for fish collection, underwater visual census is much more efficient way to investigate fish diversity and assemblages in coastal waters.