• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.05a
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• pp.469-469
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• 2000

뱀장어 Anguilla japonica는 민물에서 자라고 알을 낳을 때가되면 바다로 회유한다. 그러나, 해양에서 성숙된 뱀장어나 알이 채집되지 않아 정확한 산란기는 알려져 있지 않았다. 어류의 이석에는 하루주기로 나이테(일륜)가 형성되기 때문에 이 일륜의 수로부터 산란기를 추정할 수 있다. 지금까지 실뱀장어 이석의 미세성장선수로부터 산란기를 추정한 자료의 문제점을 분석하고, 산란장 주변에서 채집된 댓잎뱀장어(leptocephalus) 이석의 미세성장선수로부터 산란기를 추정하였다. (중략)

• KOREAN POULTRY JOURNAL
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• s.94
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• pp.90-94
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• 1977

양계경영에 있어서 점등관리는 닭의 발육, 성 성숙, 산란성과 밀접한 관계를 갖고 있으며 육성기와 산란기의 적절한 점등관리는 닭의 품종, 계통, 연령 및 능력에 못지 않게 중요하다. 광선이 닭에 주어지면 시신경을 통하여 뇌하수체 전엽에 자극이 주어져서 성선자극호르몬이 분비되며 그 호르몬의 작용에 의하여 배란이 일어나게 된다. 이러한 닭의 감광성을 이용하여 산란을 촉진하게 하는 것이 점등관리인 것이다.

• The Korean Journal of Malacology
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• v.13 no.1
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• pp.43-54
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• 1997

1994년 1월부터 12월까지 1년간에 걸쳐 우리 나라 서해안 비인만의 조간대에서 채집된 떡조개, Dosinorbis(Phacosoma) japonocus(Reeve)를 대상으로 성숙 및 산란시기를 규명하기 위해 생식소 여포지수(GFI)및 생식소지수(GI)의 월별변화, 생식주기, 월별 난경 조성 및 성비를 조사하였다. 본 종은 자웅이체이고, 생식소는 중장선 하부와 소화맹낭 그리고 섬유성 결체조직과 근섬유에 의해 치밀하게 구성된 외측 근섬유층 사이에 위치하고 있다. 산란기 추정을 위해 조사된 GFI와 GI의 월별변화 양상은 생식주기와 일치하는 경향을 보였다. 난경 55-65$\mu\textrm{m}$인 성숙란들은 젤라틴성 막에 의해 둘러싸여 있다. 본 종의 생식주기는 초기활성기 (12-2월), 후기활성기(2-5월), 성숙기(5-8월), 부분산란기(6-8월)그리고 퇴화 및 비활성기(8-12월)의 연속적인 5단계로 나눌 수 있었다. 산란기는 수온 및 먹이이용 가능성과 밀접하게 관련되어 있는 것으로 보이며, 산란은 수온이 2$0^{\circ}C$ 이상인 6월부커 8월까지 일어났고, 산란성기는 6월과 7월이었다. 산란기는 단지 그 해 하계에만 일어남으로써 1년에 1회의 산란기를 가지나 그 산란 빈도 횟수는 1년에 1회의 산란계절 중 2회 이상 일어나는 것으로 추정된다. 암.수 개체들의 성비는 통계 처리한 결과 1:1(x$^{2}$=0.08, P>0.05)로 나타나 암.수간 성비에 차이가 없었다.

• Proceedings of the Korea Society of Poultry Science Conference
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• 2004.11a
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• pp.107-108
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• 2004

산란계 육성기 제한시기 및 제한강도가 육성기 발육형태 및 산란생산성 반응을 구명하고자 1일령 갈색 산란 실용계 Isa-brown 1,000수를 공시하여 70주간 사양시험을 실시하였다. 사료급여 방법은 자유채식구와 제한급이구 9처리를 두었는데, 제한시기는 4, 6 및 8주령으로 하였고 제한강도는 각 시기별 70 %, 85 % 및 12주령 기준으로 70 %에서 85 %로 하는 처리를 두었다. 육성기 사료섭취량은 제한급이시기가 빠를수록 제한강도가 강할수록 자유채식구에 비하여 유의적으로 낮게 나타났다(P<0.05). 산란생산성은 4주령, 85 %구와 6주령 70 % 및 6주령 70 $\longrightarrow$ 85 % 전환구가 가장 우수한 것으로 나타났다. 계란 난각의 품질은 제한급이구가 산란후기에 자유채식구 대비 양호한 것으로 나타났다. 이상의 결과에서 육성기 제한급이는 육성기 사료섭취량을 절감할 수 있으며 생산성과 난각질 향상에 기여할 것으로 판단된다.

• Korean Journal of Ichthyology
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• v.7 no.2
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• pp.195-202
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• 1995

The seasonal changes in the muscle components of hibernant fish, amphibious mudskipper (Boleopthalmus pectinirostris), caught during the period between June 1993 and April 1994 were studied. The distributional changes of its major components in each muscle tissues was also observed before and after spawning and hibernation. Moisture content was the lowest after spawnig season and the highest just after hibernation, but crude protein was the highest after spawning sea-son. Crude lipid in female was the highest before spawning season, while in male it was the highest after spawning season, but both of female and male the lowest just after hibernation. Carbohydrate content in female and male showed the highest value just before hibernation and tended to decrease thereafter. In case of mudskipper, dyeing distribution was more or less spread in almost all of the tissues after spawning season but showed nearly no difference just after hibernation with the exception of small increase in dyeing degree of muco layer and epidermis layer. Investigation of mudskipper muscle tissue through the method of sudan black B dyeing yielded the results as follows ; lipid component in mudskipper in seasons before and after spawning season was percieved as mainly distributed in muco layer, epidermis and hypodermis layer respectively and also percieved a little between hypodermis subscutoneus cells. In season just before hibernation, it prevailed in almost all of the tissues, contrary to the weakness in its distribution degree just after hibernation.

• Korean Journal of Ichthyology
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• v.31 no.3
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• pp.141-149
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• 2019

This study presents data on spawning season, weight-length relationships (WLRs) and condition factor of Gadus chalcogrammus inhabiting the middle East Sea, Korea. Monthly changes in the gonadosomatic index (GSI) revealed that the spawning period was from December to March. Overall value of the exponent b, estimated by nonlinear least squares from weight and length data was 2.806, ranging from 2.778 for female fishes to 2.985 for immature group. The b values were similar between spawning and non-spawning, and between female and male fishes, but it was significantly higher for immature than mature fishes. The condition factors were significantly higher for immature than mature groups, and during non-spawning than spawning periods, but it was not significant between male and female fishes.

• Korean Journal of Optics and Photonics
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• v.13 no.3
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• pp.209-214
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• 2002

The effect of surface roughness on mirror scattering has been studied. Five kinds of substrates with different surface roughness were fabricated. On those substrates, a dielectric multi-layer coating with high reflectivity was deposited by ion beam sputtering and electron beam evaporation. A total integrated scattering measurement set-up was built for the evaluation of deposited samples. Most of the ion beam sputtered mirrors showed lower scattering than the electron beam evaporated one, which deposited on substrates similar in surface roughness. Over ~2 $\AA$ in surface roughness, scattering strongly depend on the micro-structure of the super-polished surface. The lowest scattering we have achieved is 2.06 ppm by ion beam sputtering from the substrate with surface roughness of 0.23 $\AA$.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.10a
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• pp.287-287
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• 2000

전북 식도 연안 정치망에서 1996년 6월에서 11월 사이 월별로 채집된 멸치 유어 이석의 일륜과 그 폭을 광학현미경과 주사전자현미경으로 관찰하여 산란기를 추정하고, 일일 성장률을 역추산하여 산란기에 따른 일일 성장률을 비교 분석하였다. 시상면 (sagittal plane)을 지나는 이석에는 부화 성장 정지선(hatch check)이 형성되었고, 그 외부를 둘러싼 난황 자어기에 형성된 것으로 추정되는 평균 4개의 불분명한 미세성장선이 관찰되었으며, 난황흡수성장정지선(yolk-absorption mark)이후에는 비교적 명확한 일륜이 형성되었다. (중략)

• Korean Journal of Ichthyology
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• v.7 no.2
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• pp.187-194
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• 1995

This study was carried out to obtain fundamental data on the metabolism of hibernant fish loach, Misgurnus mizolepis. Main focus was on the compositon of muscle components and its changes in fresh - water loach before and after spawning season and before and after hibernation. Distributional changes of carbohydrate, protein and lipid in the muscle tissues were also investigated. Change patterns of miosture and crude protein, and moisture and crude lipid were in inversely proportional, i.e. : moisture amount showed the lowest value after spawnig season, the highest just after hibernation, but crude protein and crude lipid were the highest values after spawning season, and the lowest just after hibernation. Carbohydrate showed the highest value just before hibernation and tended to decrease thereafter. Muco layer of epidermis and muscle cell of hypodermis layer in loach were remarkable in its PAS dyeing degree after sapwning season, and it was presumed to include high percentage of protein or carbohydrate. Dermis layer became thinner before spawning hibernation. Lipid component in female tended to distribute relatively widely in the muscle cell layer before spawning season, but in case of male mainly in muco layer and epidermis layer. It appeared that lipid was spreaded mainly in epidermis and hypodermis tissue after spawning season, while it prevailed in almost all tissues but tended to decrease after hibernation.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.22 no.3
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• pp.154-160
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• 1989

To obtain basic data on food components of triploid fish, we undertook the analysis of free amino acid, nucleotide, total creatinine, betaine, trimethylamine oxide(TMAO) and their related compounds in diploid and triploid carps(Cyprinus carpio). The contents of total free amino acid and its related compounds in belly and dorsal muscles of triploid carp were 346.1mg/100g and 333.4mg/100g. Histidine occupied $45.1\%\;and\;46.9\%$ in belly and dorsal muscles, and followed by taurine, lysine and glycine in order. As for the compositions of nucleotide and its related compounds in those muscles of triploid carp, IMP were revealed $73.9\%\;and\;65.8\%$ of total nucleotide and its related compounds. The major component of the other organic base in those muscles of triploid carp was total creatinine, but betaine and TMAO were poor. The contents of taste compounds such as free amino acid, nucleotide, total creatinine, betaine, TMAO and their related compounds were less in triploid carp than in diploid carp of nonspawning season, while were more in triploid carp than in diploid carp of spawning season. Total amino acid contents were more in diploid carp of nonspawning season than in triploid carp, but mineral contents were more in triploid carp than in diploid carp of spawning season. Therefore, it is believed that triploid carp is very worthy for a tasty and nutritional food source.