• KOREAN POULTRY JOURNAL
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• v.28 no.1 s.315
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• pp.99-105
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• 1996

• KOREAN POULTRY JOURNAL
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• v.31 no.10 s.360
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• pp.70-74
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• 1999

• Proceedings of the Korea Society of Poultry Science Conference
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• 2003.05a
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• pp.27-35
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• 2003

(시험 1) 육용종계 산란기의 단백질공급수준에 관한 연구: 육용종계 산란기의 적정 단백질공급수중을 구명하기 위하여 강원도 홍천군 북방면소재 홍천종계에서 케이지 사양형태의 아바에이카 육용종계 400수를 공시하여 2001년 2월부터 2001년 12월까지 40주간 (24∼64주령) 1일1수당 단백질 공급량을 18, 20, 22, 24g으로 달리하는 4개처리로 사양시험을 실시한 결과를 요약하면 다음과 같다. 1) 총 산란율과 종란 산란율은 모두 처리간에 유의적인 차이가 있었으며 (P<0.05), 20g 공급구가 가장 높았으나 18∼22g 공급구간에는 유의차가 없어고 24g 공급구는 20g 공급구에 비해 유의적으로 낮았다(P<0.05). 2) 평균난중은 1일 단백질공급수준이 증가할수록 증가하는 경향이었으나 (P<0.05), 20∼24g 공급구간에는 유의차가 없었고 18g 공급구만 24g 공급구와 유의적인 차이가 있었다. 성계생존율은 처리간에 유의적인 차이가 없었다. 3) 계란kg당 또는 계란1개당 사료요구율과 ME요구량은 모두 1일 CP 20g 공급구가 가장 우수했으며(P<0.05), 계란 kg당 사료요구율과 ME요구량에서는 CP 18g 공급구계란1개당 사료요구율과 ME요구량에서는 CP 24g 공급구만 CP 20g공급구오 유의차를 보였다(P<0.05). 4) 계란kg당 또는 계란 1개당 CP요구량은 모두 1일 단백질 공급량이 많아질수록 증가하였으나(P<0.05), 18g과 20g 공급구간에는 유의차가 없었다. 5) 계란kg당 또는 계란 1개당 사료비는 모두 CP 20g 공급구가 가장 우수하였으나(P<0.05), 계란1개당 사료비에서는 18∼20g 공급구간에 유의차가 없었다. (시험 2) 육용종계 하절기 산란피크계의 에너지 공급수준에 관한 연구: 육용종계 산란기의 적정 에너지공급체계를 구명하기 위하여 강원도 홍천군 북방면소재 홍천종계에서 케이지 사양형태의 로스 육용종계 400수를 공시하여 2002년 4월부터 2003년 1월까지 40주간 (24∼64주령) 표2와 같은 4가지 에너지공급체계로 사양시험을 실시한 결과를 요약하면 다음과 같다. 1) 총 산란율, 종란 산란율, 평균난중 및 성계 생존율은 모두 처리간에 유의적인 차이가 인정되지 않았으나, 산란율은 1일 에너지공급량이 많을수록 오히려 저하하는 경향을 보였다. 2) 사료요구율, ME 및 CP요구량과 사료비는 모두 1일 에너지공급량이 많아질수록 증가하는 경향을 보였다(P<0.05).

• Journal of Aquaculture
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• v.15 no.1
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• pp.23-29
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• 2002

To develop techniques for the production of artificial seedling of Corbicula japonica, protocols for induction of spawning and larval development were developed. During the assumed spawning period of August to mid-September, attempts were first made to induce spawning by gonadal incision and UV-irradiation but all in vain. At the end of August, elevated thermal induction evoked 90 % positive response in animals maintained at $3\textperthousand$ salinity. Immersion in (1/1000~3/1000 N) ammonium hydroxide ($NH_4$OH) also induced spawning in 15~45%) of the treated animals at $3\textperthousand$ salinity. Fertilized eggs measured 86$\mum. At 23.0~24.5$^{\circ}C$, the fertilized egos developed into 4-cell stage embryos within 2 hours, trochophores 15 hours, D-shaped larvae 2 days, umbo 9 days and fully grown veligers, ready to infiltrate into the sediment, within 16 days.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.4
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• pp.523-527
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• 1997

Population analysis of the common squid, Todarodes pacificus identified three seasonal cohorts in the Korean waters. They were significantly separable in terms of spawning period and fecundity, and they were slightly different in frequency distribution of egg size, while they are not significantly different in mantle length at $50\%$ maturity.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.1
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• pp.17-25
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• 1998

A fisheries biological study on the hairtail (Trichiurus lepturus LINNAEUS), which was collected from Cheju City, Hanrim, Sungsanpo and Seogwipo in Cheju Island, was carried out from June through December In 1992. GSI of the hairtail maintained relatively high from June to September, and then it began to decrease in October and remained low until December. The maturation and spawning period was between June and October, and the major spawning occurred in August. The hairtail turned out to be a multiple spawning species which spawn two or three times In a single spawning season. During the spawning season the number of females was greater than that of males, whereas the sex ratio was almost 1 : 1 during the rest of the season. Fecundity estimated from various sizes of the hairtail ranged from 12,821 to 125,876. The bigger the snout anal length and body weight of the hairtail was, the more eggs it possessed.

• Journal of Marine Life Science
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• v.7 no.1
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• pp.37-44
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• 2022

This study was performed to obtain information on the sex ratio, size at sexual group maturity, and main spawning period of Glyptocephalus stelleri. The sex ratio (female: male) was 1:0.54 (n=189:103, 64.7% female), and the frequency of females in the population tended to increase with total length. The oocyte development pattern was group synchronous development, in which oocyte groups at different stages were identified within the same ovary. The total length at 50% sexual group maturity was analyzed using a logistic regression model, and was determined to be 28.51 (female) and 30.49 cm (male). The gonadosomatic index (GSI) displayed the highest values in April (female) and March (male), and the main spawning period being in April to May.

• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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• v.24 no.1
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• pp.75-78
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• 2013

• Proceedings of the Acoustical Society of Korea Conference
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• spring
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• pp.433-438
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• 2002

연안역의 천해 해저면에 설치된 ADCP(Acoustic Doppler Current Profiler, 300kHz, 1200kHz)를 이용, 천해에서 체적 산란강도(volume scattering strength) 수직분포의 시간적인 변동 특성을 알아보았다. 수심 85m와 113m에서 ADCP로 측정한 산란강도의 일주기 변동성은 동물플랑크톤(zooplankton)으로 추측되는 산란체의 일주기 수직 이동(daily vertical migration)의 원인으로 추정되었다. 그러나 수심 20m의 천해에서 관측된 산란강도의 시변동성은 경험적 직교 함수(Empirical Orthogonal Function, EOF) 분석 결과 해저면 부근의 변화가 천해 체적 산란의 변동성에 큰 영향을 주는 것으로 나타났다.

• Korean Journal of Poultry Science
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• v.25 no.4
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• pp.177-183
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• 1998

A feeding trial was conducted to investigate the performance of various Korean Native Chickens (KNC) for 64 weeks. Eight hundreds and ten KNC one-day birds were arranged to three strains, Dark Brown(D), Light Brown(L) and Black(B). Each strain had three replicates of 90 birds a replicate. Birds fed same diet with Korean standard feeding. Data were obtained growing performance to 20 week of age and laying performance from twenty one to sixty four week. During the growing stage from hatch to 20 week of age, there were not significant difference to three strains on viability, body weight and feed intake. L strain tended to be earlier 50％ egg production day than that of other strains, but was not significantly different. Egg production of L strain was the highest of strains. It showed significantly higher egg production compared to that of D strain(P<0.05), but was not statistically different from that of B strain. Laying peak period was between 28 to 32 week of age in all strains, Egg weight was heavier in D strain(P<0.05). Feed intake was the same as 105g, and feed conversion improved in L strain(P<0.05). There were not difference on interior egg and eggshell quality by strains although eggshell thickness improved slightly in D strain. Fertility of D strain was the highest compared to others(P<0.05) regardless laying stages. Hatchability was not influenced by strains at 39 weeks old, but was significantly higher in B strain at 62 week of age(P< 0.05). The results of this experiment indicated that KNC 3 strains were not effect on egg production, feed intake and feed conversion ratio.