• 한국어업기술학회:학술대회논문집
• /
• 한국어업기술학회 2003년도 춘계 수산관련학회 공동학술대회발표요지집
• /
• pp.225-226
• /
• 2003

Catfish (S. asotus) and bullhead (P. fulvidraco), economically important aquacultural species, belonging to order Siluriformes including two family Siluridae and Bagridae, respectively, are considered to be closely related to each other by various authors. Two fish species widely inhabit the slow river and stream that flows to the West Sea and South Sea in the Korean Peninsula. (omitted)

• 한국해양생명과학회지
• /
• 제8권2호
• /
• pp.115-120
• /
• 2023

본 연구는 동자개 정자의 동결보존을 위해 동결보존제의 최적 농도와 적정 희석액을 구명하여 정자를 최상의 상태로 보존하여 인공종자를 생산하는데 목적이 있다. 실험은 3종의 희석액(I: 300 mM glycose, II: Kurokura extender, III: Li extender), 4종의 동결보존제(dimethyl sulfoxide, ethylene glycol, methanol and glycerol)와 4개의 동결보존제 농도(5, 10, 15, 20%)를 조합하여 대하여 조사하였다. 동결보존한 정자를 해동한 후 정자의 생존율과 정자활성지수로 동결보존제의 효과를 평가하였다. 희석액 III(Li extender)과 10과 15%의 methanol을 조합했을 때 동자개 정자의 생존율과 정자활성지수는 각각 66.9 ± 8.7, 67.3 ± 13.1%과 2.6 ± 0.4, 2.6 ± 0.5로 다른 희석액과 동결보존제보다 높았다.

• 한국수산과학회지
• /
• 제46권4호
• /
• pp.377-383
• /
• 2013

We ran a feeding trial to determine optimal dietary protein and lipid levels for growth of juvenile long snout bullhead Leiocassis longirostris Gunther. Eight experimental diets (P20L7, P20L14, P30L7, P30L14, P40L7, P40L14, P50L7 and P50L14) were formulated to contain 20%, 30%, 40% or 50% protein combined with either 7% or 14% lipid. Three replicate groups of fish (mean mass: 3.9 g/fish) were fed one of the experimental diets ad libitum for 8 weeks. Survival of fish fed the P20L14 diet was lower than that of fish fed the P40L14, P50L7 and P50L14 diets. Growth of fish fed diets containing 7% lipid increased with increasing protein level (up to 50% protein); growth of fish fed diets containing 14% lipid increased with increasing protein level (up to 30% protein). The feed efficiency of fish fed a diet with 50% protein and 7% lipid was higher than that of other groups. Whole body moisture and lipid contents were affected by dietary lipid level but not by dietary protein level. The crude lipid contents of fish fed 14% lipid diets were higher than those fed 7% lipid diets across all protein levels (other than the 50% level). Thus, under our experimental conditions, an increase in dietary protein level improved growth and feed efficiency of fish; a diet containing 50% protein with 7% lipid was optimal for growth and effective feed utilization in juvenile long snout bullhead.

• 한국양식학회지
• /
• 제11권2호
• /
• pp.151-158
• /
• 1998

동자개의 배란유도에 대한 LHRH-a, pimozide 및 HCG의 복강내 투여효과에 대해 조사하였다. 어체중 kg당 HCG를 각각 5,000, 10,0000, 20,000 IU를 주사하였을 경우 71.4, 80, 100%의 배란유도율을 나타냈다. 또한 pimozide의 존재에 관계없이 LHRH-a를 주사한 개체들 대부분이 배란되었다. LHRH-a 단독투여 실험에서 kg당 200, 200, $400^{\mu}$g 처리에서 각각 50, 75 및 100%의 배란유도율을 나타냈다. pimozide첨가는LHRH-a의 작용을 향상시켰다. 즉, LHRH-a와 pimozide의 혼합투여에서 어체중 kg당 pimozide 1 mg과 LHRH-a $300^{\mu}$g에서 100%의 가장 좋은 배란유도율을 나타내었다. 그러나 pimozide 단독투여에서 배란이 유도되지 않았다. 호르몬 처리후의 생식소숙도지수(GSI)와 pesudo-GSI의 변화를 조사한 결과, HCG, LHRH-a 및 LHRH-a+pimozide를 주사한 그룹간의 생식소숙도지수(GSI)와 pseudo-GSI에 있어서 퉁계적인 유의차는 없었다(P>0.05). 호르모처리후 배란이 일어나기까지의 소요시간은 HCG처리후 17~22시간, LHRH-a단독 또는 pimozide와의 혼합처리에서 대체로 23~29시간이 걸렸다.

• 한국수산과학회지
• /
• 제49권6호
• /
• pp.779-784
• /
• 2016

We evaluated seasonal variations in the proximate, fatty acid and total amino acid compositions and mineral content of the muscles of wild and cultured Korean bullhead Pseudobagrus fulvidraco. The wild and cultured samples showed a significantly higher proportion of crude lipids than other components. Crude lipid content was highest in May in wild fish but lowest in May in cultured fish. We found no significant difference between wild and cultured samples in terms of fatty acid and total amino acid compositions and mineral content. The levels of saturated fatty acids (SFA) and polyunsaturated fatty acids (PUFA) as well as n-6/n-3, were higher in the muscles of wild fish compared with those of cultured fish. However, monounsaturated fatty acids (MUFA) levels were higher in cultured fish. Both wild and cultured fish were good sources of eicosapentaenoic acid (EPA) and docosa hexaenoic acid (DHA). In wild fish, the Mg and Zn contents were highest in August, while the Ca, P, Na, K, Fe, and Cu contents were highest in May. However, the mineral content of the cultured fish did not exhibit significant seasonal variation.

• 한국발생생물학회지:발생과생식
• /
• 제22권1호
• /
• pp.9-18
• /
• 2018

This study was conducted to investigate the skeletal development of bullhead torrent catfish, Liobagrus obesus larvae and to utilize them as basic data for the taxonomic study of Liobagrus larvae. Skeletal development was observed by being divided into cranium, visceral skeleton, shoulder girdle bone, pelvic girdle bone and vertebra. On the first day after hatching, the pre-larvae had an average total length of 7.92 mm, and a line-shaped parasphenoid ossified in the cranium. In the jaw bone, the dentary supporting the lower jaw and the maxillary supporting the upper jaw were ossified. In the anterior abdominal vertebrae of the vertebra, seven centrums began to ossify and five neural spines ossified simultaneously. On the 3 day after hatching, pre-larvae had an average total length of 8.95 mm, and the prefrontal ossified in cranium. The number of abdominal vertebrae was increased to 14, and three parapophysis developed from the front side. On the 24th day after hatching, post-larvae had an average total length of 15.2 mm and the epural bone ossified in coccyx. The parhypural bone was ossified, and ossification of coccyx and pelvic girdle bone was completed. On the 30th day after hatching, the average total length of the juvenile was 17.8 mm, and the ossification of cranium and visceral skeleton was all completed while the preorbital and three suborbitals were ossified in the orbital region of the cranium.

• 한국어류학회지
• /
• 제13권1호
• /
• pp.74-84
• /
• 2001

사육 조건하에서 동자개 Pseudobagrus fulvidraco의 발육에 따른 형태 변화 및 상대성장에 대해 검토하여 발육단계를 구분한 결과를 요약하면 다음과 같다. 1. 수정난은 난경 2.04${\pm}$0.07 mm (n = 100)의 비교적 큰 구형의 분리되는 침성부착난으로서 수조의 바닥 및 기질에 강하게 부착한다. 2. 부화자어는 전장 약 4.92${\pm}$0.33 mm로, 부화 후 1일에 입이 열리고, 부화 2일후에는 항문이 열리고, 부화 후 3일에 섭이를 시작하여 후기자어기에, 부화 후 30일경에 전장 약 32 mm에 유어기에 이른다. 3. 전장에 대한 각 부위의 상대성장에 굴곡점은 전장 7~8 mm, 17~32 mm, 32 mm 전후에 집중적으로 나타났다. 4. 외부형태의 변화 및 상대성장의 굴곡점이 나타나는 어체 크기 등을 종합적으로 고려하여 자어기에서 유어기까지의 발육단계를 구분하면, 자어기는 전장 17 mm 이하, 치어기는 17~32 mm, 유어기는 32 mm 이상으로 사료된다. 상대성장의 측정결과 전기자어기에는 머리부분에 관련된 형질, 후기자어기 이후에는 운동능력에 관련된 형질의 우성장이 뚜렷하였다.

• 한국환경생물학회:학술대회논문집
• /
• 한국환경생물학회 2004년도 학술대회
• /
• pp.108-110
• /
• 2004

• 한국동물학회:학술대회논문집
• /
• 한국동물학회 2000년도 한국생물과학협회 학술발표대회
• /
• pp.183.3-184
• /
• 2000

No Abstract, See Full Text

• 한국유체기계학회 논문집
• /
• 제14권6호
• /
• pp.18-25
• /
• 2011

A boundary-layer pump with a single disk has been experimented to obtain its characteristic curve by changing the impeller of a centrifugal pump to a single disk. The primary objective to use of these types of pumps is to avoid hurting water life during transportation unnecessarily. The change of impeller should degrade the performance of pump, so we used the method to increase the roughness on the disk with sandpaper and mesh. The enhancement of shear force from the rotation of disk to the internal flow brought an augmentation of momentum transport, and the characteristics were far improved from the original single-disk pump without decreasing the survival rate of water life in the case of Pseudobagrus fulvidraco (bullhead fish). However, in the case of Artemia cyst (zooplankton), the survival rate was very degraded due to the micro scale smaller than turbulent eddy size. The result of this study could be used for the design of transportation and bio-filtering of water lying on a specific bandwidth of its scale of size.