• 한국어병학회지
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• 제8권1호
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• pp.1-11
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• 1995

한국산 어류 (전어) 아가미에서 기생성 요각류 2 종, Nothobomolochus thambus (Poecilostomatoida, Bomolochidae) 와 Mitrapus heteropodus (Siphonostomatoida, Lernanthropidae) 이 채집되었다. N. thambus 은 특이한 턱다리의 구조를 가지므로 Nothobomolochus 속 다른 종과 쉽게 구별된다. ; 턱다리의 큰 강모 2 개중 1 개는 잔털을 갖지 않는다. ; M. heteropodus 의 주요 특징은 4번째 다리의 구조이다 ; 4 번째 다리의 안다리는 바깥다리의 1/5 크기이다. 이들은 모두 한국 미기록종이다.

• Fisheries and Aquatic Sciences
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• 제26권4호
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• pp.256-267
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• 2023

The suitability of any fish species for successful aquaculture requires basic information on its reproduction and growth. This study investigated some facets of the reproductive biology of Synodontis shall (Mochokidae) from River Siluko in Nigeria. Fish samples were collected forth-nightly for a duration of fourteen (14) months-March 2015 to April, 2016 with the assistance of artisanal fishermen. Fishes were identified using taxonomic guides and standard techniques were used for determination of sex ratio, gonad maturation and fecundity. Linear regression method was used to define the correlation between fecundity and fish length, body weight and ovary weight. Results showed that sex ratio did not indicate a significant divergence (p > 0.05) from the 1 male to 1 female distribution ratio (1:1.41). Gonad morphology revealed paired gonads. Testes and ovaries were classified into four maturity stages: immature, resting, ripening and ripe. Gonadosomatic index ranged from 0.04 to 5.68 (males) and 0.03 to 20.19 (females). Absolute fecundity ranged from 1,014 to 4,520 eggs (mean = 2,592 eggs) and did not correlate significantly (p > 0.05) to ovary weight. This study has contributed to existing data on the biology of freshwater fish species in Nigeria and provided valuable information for fishery management tools in the conservation and utilization of this valuable freshwater fish species.

• 수산해양기술연구
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• 제60권2호
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• pp.186-193
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• 2024

Most fishing nets used in fish cage aquaculture are made of synthetic fibers such as polyamide (PA) and polyethylene (PE). Therefore, it is challenging to maintain the internal volume of the fish cage due to biofouling, which can increase the load on the cage or reduce dissolved oxygen levels by impeding smooth current flow. To address this issue, research has been conducted to replace conventional synthetic fiber cage nets with brass nets, demonstrating certain benefits such as improved productivity and ease of fish cage management. However, given the need for a more thorough examination of brass fishing net weaving technology and performance, this study assessed the optimal weaving method for brass fishing nets to be used in fish cages. Additionally, it provided essential data for the practical application of brass fishing nets by evaluating their weight, tensile strength, elongation, fatigue resistance, and wear resistance. The study concluded that weaving brass fishing nets using the chain link method ensures durability, ease of installation, and compact storage in a scroll-like form. Moreover, due to their superior fatigue and wear resistance properties, brass nets can offer increased utility if appropriate net diameter and length are selected to compensate for their higher weight per unit area and relatively higher cost compared to existing fiber fishing nets.

• 수산해양기술연구
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• 제51권1호
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• pp.102-110
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• 2015

The characteristics of aquatic light fields are generally reflected in the visual systems of fishes inhabiting them. Therefore, research on light sensitivity of fish is useful to explain the correlation between the visual function and habitat, behavior and distribution of fish. Rockfish is an important species in coastal ecology and also one of the main species for culturing in Korea. To make a contribution on the maintenance of the fish resources and understanding the ecology of the rockfish, the visual spectral sensitivities of the dark-adapted rockfishes were measured in the range of visible light (405~660 nm) using a light source of light-emitting diodes (LEDs). In order to assess electrophysiological response of the fish, the ERGs (electroretinograms) of the dark-adapted rockfishes were recorded on a data logger (12 bits) and a laptop computer. Juvenile (n=5; weight: $20.3{\pm}5.2g$; total length: $10.3{\pm}0.7cm$) and adult (n=5; weight: $87.8{\pm}21.8g$; total length: $18.1{\pm}1.3cm$) rockfishes were used in experiment. The visual threshold of juvenile and adult rockfish were 11.66 (log quanta/$cm^2/s$) and 11.81 (log quanta/$cm^2/s$) in 574 nm, respectively. The peak wavelength of the spectral sensitivity in the dark-adapted juvenile and adult rockfish was commonly 551 nm (series of green color). Collectively, these results demonstrate that the rockfish has suitable visual capabilities for inhabiting coastal water in Korea.

• 한국약용작물학회지
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• 제11권5호
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• pp.402-407
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• 2003

개시호 (Bulpleurum longeradiatum)를 대상으로 상염 색법과 FISH기법을 통한 염색체 분석을 통하여 다음과 같은 결과를 얻었다. 개시호의 체세포 염색체 수는 2n=12이었으며, centromeric index를 전중기 염색체를 이용한 핵형 분석에서 염색체 조성은 3쌍의 중부 염색체 (3번, 4번 및 6번)와 3쌍의 차중부 염색체 (1번, 2번 및 5번)로 구분되었다. 염색체의 길이는 $2.55{\sim}5.05\;{\mu}m$로, 전체 길이는 $18.15\;{\mu}m$로 나타났다. 5S 와 45S rDNA를 탐침으로 FISH를 수행한 결과 4번 염색체의 동원체 부위 에서 한 쌍의 5S rDNA signal이 확인되었고, 2번 염색체의 부수체에서 한 쌍의 45S rDNA signal이 관찰되었다.

• 한국어병학회지
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• 제19권2호
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• pp.99-108
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• 2006

Diseased tiger puffer (Takijugu rubripes) showed anorexia and severe anemia in the gills. In wet mount preparations Heterobothrium sp. with 4 sets of clamps on the opisthohaptor attached to the gill filaments of the diseased fish. From the drum-shaped filter for filtration of the culturing water and the sediment of aquarium held the diseased fish in the laboratory, their eggs forming long strings through connection of the bipolar filaments could be easily collected. The parasites with 4 pairs of clamps on the opisthohaptor were 2.38mm in length and 0.71 mm in width, but had no isthmus which was separated the opisthohapor from the body proper. The parasites could be easily distinguished from Heterobothrium tetrodonis and H. okamotoi in the absence of distinct isthmus, and resembled H. yamagutii described from the gills of Takifugu xanthopterus in Japan. Their eggs were yellowish spindle in shape and 180-200 x 5-6 Iffil in size, which were pointed at both ends. The eggs were linked to adjacent egg shells like a string of beads by the filaments. Onchomiracidia, ciliated larvae spawned from the eggs were 133 Iffil (120-146 Iffil) x 751ffil (68-80 Iffil) in size. The length of the ciliates was 12 Iffil in the anterior part of the larvae and 14 Iffil in the posterior part. Round or leaf-shaped young parasites attached on the secondary gill lamellae. There was a tendency that most of round smaller parasites without an opisthohaptor were found in the middle part of the gill lamellae while leaf-shaped larger ones with a opisthohaptor attached on the distal part of the gill filaments. Each clamp of mature parasites grasped one secondary gill filament which resulted in bending of the filaments and hyperplasia of the epithelium and mucous cells. In the branchial cavity around the pseudobranch, mature parasites grasped the adjacent ones by means of the clamps, and the epithelia of the branchial cavity around the parasites showed severe irregular hyperplasia and erosion with strongly PAS-positive mucous cells.

• 한국수산과학회지
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• 제18권5호
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• pp.484-490
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• 1985

우리나라 서해안의 경기만에서 채집한 횐베도라치 개체군의 식성을 파악하기 위하여 흰베도라치 소화관내용물과 환경생물을 비교연구한 결과는 다음과 같다. 1. 흰베도라치의 먹이생물은 체장에 따라 다소의 차이는 있으나 대체로 환경에서 우점적으로 출현하는 요각류의 Paracalanus parvus, Corycaeus affinis, Calans sinicus를 주로 섭이하며 미색류, 어란, 십각류 유생도 체장에 따라 다소높은 먹이생물로 나타났다. 2. 흰베도라치 치자어의 먹이에 대한 선택성은 대체로 성장함에 따라 점진적으로 높아지는 현상을 보였다. 즉 체장이 커질수록 요각류를 선호하며, 체장 45.0mm부터는 미색류를 많이 섭이하는 경향이었다. 그러나 체장 45.0mm부터 십각류유생이 대한 선택성은 감소되어 소극적 섭이를 하였고, 전 체장군에서 모악류의 섭이량은 별로 많지 않는 것으로 나타났다. 3. 흰베도라치의 먹이생물크기에 대한 선택성은 뚜렷하지 않으며 우점적으로 출현하는 먹이생물의 크기에 좌우되는 것으로 나타났다. 4. 흰베도라치의 성장함에 따른 먹이생물의 중요도는 전 체장군에서 요각류가 높게 나타났으며, 체장에 따라 어란도 다소 높았다. 체장 45.0mm부터는 십각류유생에 대한 선택성은 감소하였으나 먹이생물로서의 중요도는 높게 나타났다. 요각류의 종별 중요도에서는 체장 36.0mm 이하에서 P. parvus, C. affinis가 높았고, 체장 $45.0{\sim}46.0mm$에서는 C. sinicus가 높게 나타났다.

• Fisheries and Aquatic Sciences
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• 제21권11호
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• pp.34.1-34.13
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• 2018

Sexual maturity ($L_{50}$), the length at which 50% of fish in a size class are mature, is a key aspect of domestication of new fish species because it guides the procedure for identification of appropriate broodstock size for artificial spawning. In this study, the $L_{50}$ was determined for 1083 Barbus altianalis samples obtained from Lake Edward and the Upper Victoria Nile. Gonads of freshly killed samples were examined macroscopically and verified with standard histological procedures for the maturation stages that were used to determine $L_{50}$. Oocytes and spermatogenic cell sizes were compared for fish obtained from both water bodies. Results indicated that there were no variations in macro gonad features observed for fish from Lake Edward and Upper Victoria Nile. Similarly, there were no significant differences in oocyte sizes (P > 0.05) between the two populations but significant differences in spermatogenic cell sizes were noted (P < 0.05) except for spermatozoa (P > 0.05). This however did not suggest peculiar differences between the two populations for staging the gonads. Consequently, no staging variations were suggested for both populations in determination of $L_{50}$. Sexual maturity was found in the same class size of fork length (FL) 20-24.9 cm and 35-39.9 cm for males and females from both water bodies, respectively. At this FL, however, males were too small, and for good selection of vigor broodstocks for spawning and conservation purposes, they are better picked from class size of 30-34.9 cm FL and above. These findings were crucial for integration of appropriate breeding size in spawning protocol by farmers and fisheries scientists conserving wild B. altianalis populations.

• 한국수자원학회논문집
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• 제56권spc1호
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• pp.1037-1048
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• 2023

하천에 설치된 댐, 보 등과 같은 횡단구조물은 수생태계에 영향을 미치며 종적 연결성을 단절하기 때문에 어류의 이동을 확보하기 위하여 어도가 설치된다. 그러나 어도 내부의 흐름 특성 및 어종에 따라 어류의 통과효율의 차이가 발생한다. 본 연구에서는 3차원 RANS 모형과 자유수면 해석을 위한 VOF (volume of fluid)기법을 적용한 수치모형을 활용하여 계단식 어도에서 발생하는 난류흐름을 수치모의 하였다. 계단식 어도의 pool의 길이 변화 및 상류 수위 변동을 고려하였으며 이들의 변화에 따라 평균유속 및 난류운동에너지 분포를 분석하였다. 표면류 및 잠입류 특성을 잘 재현하였으며 pool의 길이가 증가하면서 표면류에서 잠입류로 변화하였고 상류 수위가 증가함에 따라 표면류 특성이 명확하게 나타났다. 어도 내 어류의 이동과 관련된 수리학적 인자는 유속 및 난류운동에너지 등이 있으며 이를 바탕으로 어류의 소상 가능성을 검토하였다.

• 한국환경생태학회지
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• 제27권6호
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• pp.695-703
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• 2013

2011년 4월부터 2012년 5월까지 복원된 청계천 수역에서 어류상과 참갈겨니(Zacco koreanus) 개체군을 조사하였다. 출현한 어종은 총 3과 24종이었고 고유종은 각시붕어(Rhodeus uyekii), 줄납자루(Acheilognathus yamatsutae), 가시납지리(Acheilognathus gracilis), 몰개(Squalidus japonicus coreanus), 참갈겨니(Zacco koreanus) 등 이었다. 각 조사지점에서 우점종은 피라미(Zacco platypus, St. 1, 3, 4)와 참갈겨니(St. 2) 이었다. 2008년 이전 조사와 비교 시 본 조사에서 새로 출현한 어종은 각시붕어, 가시납리리, 참마자(Hemibarbus longirostris), 줄몰개(Gnathopogon strigatus), 몰개, 모래무지(Pseudogobio esocinus), 강준치(Erythroculter erythropterus), 민물검정망둑(Tridentiger brevispinis) 등 이었다. 인위적인 방류로 도입된 종은 비단잉어(Cyprinus carpio), 중국붕어(Carassius auratus,), 금붕어(Carassius auratus), 갈겨니(Zacco temmincki), 참갈겨니, 미꾸라지(Misgurnus mizolepis) 등으로 추정된다. 참갈겨니 전장과 체중의 관계식 회귀계수 값은 $3.58(BW=0.000007T{_L}^{3.58})$이었고 비만도 (K)는 평균 0.82이었다. 전장이 20~80mm는 만 1년생, 90~120mm는 만 2년생, 130mm 이상은 만 3년생 이상으로 추정되었다. 참갈겨니는 청계천에서 도입된 이후 안정적으로 산란이 이루어지고 있는 것으로 추정되었다.