• 한국작물학회지
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• 제29권3호
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• pp.254-260
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• 1984

본 시험은 소맥 조숙품종 육성을 위한 기초 연구로서 소맥 60품종을 국내 4개소(수원, 이리, 밀양, 무안)에 공시하여 출수기와 성숙기 및 숙기에 관여하는 내적 요인인 파성, 광주반응. 협의의 조만성 및 내한성을 조사하였으며, 또한 간장 등 일반특성 및 수량구성형질과 조숙성과의 관계를 분석하였던 바 그 결과를 요약하면 다음과 같다. 1. 소맥의 출수, 성숙기는 품종 및 지역간에 고도의 유의성을 보이나 품종과 지역의 교호작용에는 유의성이 없어 품종 자체의 조만성에 따라 어느 지역에서도 안정된 반응을 보였다. 2. 등숙일수는 출수, 성숙기와 같이 어느 지역에서도 안정된 반응을 보였으나 조숙품종군들은 지역간에, 만숙품종군들은 품종간에 고도의 유의한 차이를 보였다. 3. 파성정도가 낮을수록 출수 및 성숙기가 다소빠른 경향을 보였다. 4. 소맥의 출수기의 조만은 협의의 조만성, 광주반응, 파성. 내한성 및 등숙일수 등이 관여하나 파성 및 내한성은 조숙품종들과, 광주반응 및 등숙일수는 만숙품종들과 더 높은 상관관계를 보였다. 5. 4개 시험지 각각에서 출수기에 가장 크게 기여하는 내적 요인은 협의의 조만성과 파성이었음이 확인되었으며, 내한성은 출수기와도 고도의 부의 상관관계를 보였다. 6. 소맥의 출수 및 성숙기가 빠를수록 간장 및 절간장이 짧았는데 이는 만숙품종군보다 조숙품종군에서 더 현저하였다. 7. 출수 및 성숙기는 용적중 및 월동전 경수와 부의 상관을, 그리고 일수입수와는 정상관을 보였다.

• 한국초지조사료학회지
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• 제11권3호
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• pp.145-152
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• 1991

This experiment was carried out to investigate the effects of liming, manure application, and inoculation with Rhizobium on the early growth, nodulation, seedling establishment, winter survival, and forage yield and quality of alfalfa(Medicago sativa L.) at the Experimental Livestock Farm, College of Agriculture, Seoul National University, Suweon in 1985 and 1986. The results obtained are as follows: 1. Seedling vigor and nodule formation of alfalfa at early stage were the best in the treatments of liminginoculation( L1) and liming-manure-inoculation(LM1). 2. Seedling establishment was not significantly affected by the treatments of liming, manure application, nodulation and the combination of these. 3. The LI and LMI treatments showed the highest winter survival of 94.3 and 83.5%, respectively, but the lowest winter su.rvival of 55.9 and 58.5% was found in no treatment(None) and inoculation( I ), respectively. 4. No differences in crude protein(CP1, acid detergent fiber(ADF) and neutral detergent fiber(NDF) contents were found among the treatments. 5. There were significant differences in the total dry matter yield of alfalfa among the treatments. The total dry matter yields of 10,618, 11,830, 11,855 and 13,456 kg/ha from the treatments of L, LM, LI and LMI, respectively, were significantly higher than those of None, M and I treatments. 6. Based on the results of the experiment, it appears that the dry matter yield of alfalfa could be enhanced by the treatments of liming with Rhizobium inoculation and also liming, manure application and Rhizobium inoculation as a practical method.

• Asian-Australasian Journal of Animal Sciences
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• 제17권12호
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• pp.1669-1673
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• 2004

Milk yield, lamb birth weight and weaning weight responses to shearing during winter in sheep were investigated. A total of 46 Karayaka ewes were allocated into two treatment groups. Pregnant ewes in one group were shorn on day 100 of gestation (Shorn, n=24) and the remaining ewes were left unshorn to serve as controls (Unshorn, n=22). The ewes were maintained on pasture during the day and housed in the evenings. Lamb birth weight, weaning weight and ewes'' daily milk yield in fifteen dayintervals until weaning (75 days) were recorded. Shearing ewes on day 100 of pregnancy increased gestation length (p<0.01) compared to unshorn ewes (147.8${\pm}$0.45 vs. 145.9${\pm}$0.42 days). Birth weights of lambs from shorn ewes on day 100 of their pregnancy were higher (p<0.01) than those from unshorn ewes (3.7${\pm}$0.11 vs. 3.2${\pm}$0.07 kg). Shearing pregnant ewes increased (p<0.05) the lamb weaning weight at day 75 post-lambing (23.6${\pm}$1.10 vs. 19.5${\pm}$0.91). It also increased milk yield (p<0.05). Milk yields on day 75 of lactation were 302${\pm}$33 and 425${\pm}$25 g per day for unshorn and shorn ewes on day 100 of pregnancy, respectively. Lamb survival at weaning was higher (p<0.05) in lambs from shorn ewes compared to those from unshorn ewes. In conclusion, shearing pregnant ewes in winter months enhanced milk yield, lamb birth weight, lamb weaning weight and lamb survival. It is suggested that increasing both lamb birth weight and subsequent milk yield of dams by shearing ewes on day 100 of pregnancy during winter may improve postnatal lamb viability.

• 한국작물학회지
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• 제46권4호
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• pp.296-302
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• 2001

Winter cereals are acclimated during wintering, and thereafter their freezing resistance is increased. In order to analyze inheritance and heritabilities for photoinhibition of photosynthesis by high light intensity under low temperature, and to evaluate the relationship between low temperature-induced photoinhibition and winter survival, 4 parental half diallel crosses were used. The detached leaves of 7-8cm long from plants grown for 35 and 55 days were placed on wet filter paper and placed in trays at 5$^{\circ}C$ cold room with 1,200 $\mu$mol $m^{-2}$ $s^{-1}$ PPFD. Chlorophyll fluorescence was measured with a chlorophyll fluorescence system after dark adaptation for 30 min. The Fv/Fm of 35day old plants was reduced from 0.714 in the control leaves to 0.409 and 0.368 following photoinhibitory treatment of 6h and 8h and the CVs were increased from 0.8% to 22.2-22.3%. The Fv/Fm of 55-day old plants was reduced from 0.775 in the control leaves to 0.485 and 0.439 following photoinhibitory treatment of 10h and 12h, respectively. According to half diallel cross analysis, Reno and Dongbori 1 (highly resistant to photoinhibition) was dominant, but Oweolbori (susceptible to photoinhibition) was recessive, and photoinhibition showed partial dominance with highly additive gene action. Dongbori 1 showed the greatest GCA effects for photoinhibition, and GCA/SCA ratios (8.7-22.3 times) indicated that the additive variance for the character was more important. Winter survival in barley crosses was positively correlated with resistance to photoinhibition and significantly fitted by linear regression ($R^2$=0.751$^{**}$-0.779$^{**}$). The chlorophyll fluorescence measured by Fv/Fm has been found to be highly inheritable and very useful in evaluating relative levels of freezing resistance in barley.ley.

• 수산해양교육연구
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• 제27권3호
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• pp.718-724
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• 2015

To survey the most feeding frequence of formulated diet as food for cultured puffer in winter season, we performed a rearing test using juveniles of river puffer, Takifugu obscurus (body weight 15.0 g) for 120 days. The feeding frequencies were set up as 2times/1day, 2times/2days, 2times/3days and 2times/4days. We tested triplicately the experiment and investigated survival rate, daily food intake (DFI), feed efficiency (FE), condition factor (CF), daily growth rate (DGR). Consequently, growth was increased following to an increasing of feeding frequency, was the fast in 2times/1day of feeding frequency, and was the slowest in 2times/4days (p<0.05). DFI and CF were increased following to an decreasing of feeding frequency and was the highest in 2times/4days of feeding frequency. FE was decreased following to an decreasing of feeding frequency, and was the highest in 2times/1day of feeding frequency. In a proximate carcass composition at the final day, moisture and crude lipid contents were the lowest in 2times/4days, and in survival, there was not any significant difference among experimental groups. Therefore, we concluded that the 2times/2days are the best of feeding frequency for economical benefit of river puffer culture in winter season.

• 한국패류학회지
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• 제27권3호
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• pp.193-198
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• 2011

인위적 수온급변이 참가리비의 생존율에 미치는 영향을 조사하였다. 수온변화는 봄과 여름철에 동해안에서 나타나는 변화양상을 실험실 내 사육수조에서 인위적으로 유도하였다. 봄철 저수온 기간 중 수온 자극에 의한 참가리비의 생존율은 평균 51.6%를 보였고, 소형패 (85.82%) 와 대형패 (55.0%) 보다 중형패에서 4.4%로 가장 낮았다. 여름철 고수온 기간 중 수온 자극에 의한 참가리비의 생존율은 평균 43.3%를 보였으며, 중형패 (60.0%) 보다 소형패가 46.7%로 낮게 나타났다. 대체적으로 봄철보다 여름철에 생존율이 더 낮았다. 이와 같은 결과들은 참가리비의 폐사가 수온 변화와 밀접한 관련이 있음을 보여주고 있다. 봄철 중형패의 낮은 생존율은 충분한 영영 공급을 받는 소형패나 두 번의 겨울을 보내 수온변화에 적응한 대형패에 비해 충분히 성장하지 못한 상태에서 겨울을 보내기 때문에 나타나는 결과로 보인다.

• 한국수산과학회지
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• 제49권3호
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• pp.343-350
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• 2016

The sea cucumber Apostichopus japonicus is a commercially valuable aquaculture species in Korea. Aquaculture species require specific nursery culture conditions to increase survival and growth rates. Sea cucumbers hibernate during the high temperatures of summer and during the low temperatures of winter, and suboptimal temperature conditions decrease sea cucumber growth and survival rates. The natural South Korean environment is very unfavorable for culturing sea cucumber; therefore, developing a recirculating aquaculture system (RAS) capable of breeding and growing sea cucumber year-round is necessary. The aim of this study was to investigate growth performance of juvenile sea cucumber in a RAS. Growth and survival rates of juvenile sea cucumber were high during our 24-week experiment. Sea cucumber survival rates were 87.8-93.3%, and specific growth rates were 0.4689-0.7846.

• 한국수산과학회지
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• 제53권5호
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• pp.725-732
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• 2020

The sudden drop of water temperature in winter is very threatening factor that affects the productivity of farmed fish and the management in aquafarm. In this study, we investigated the effect of low temperature on the survival, oxygen consumption and stress responses of parrotfish Oplegnathus fasciatus due to acute drop of water temperature. The survival rate of parrotfish Oplegnathus fasciatus was 5% at 6℃, 95% at 8℃ and 100% at 10℃ on the 4^th day of exposure in each experimental temperature. Low-lethal temperature for 4days of parrotfish Oplegnathus fasciatus (4 day-LT₅₀) was 6.99℃ (confidence limit, 6.55-7.42℃). Oxygen consumption rate was significantly decreased with decreasing water temperature. Temperature coefficient (Q₁₀) was found to be 4.0 between 10℃ and 8℃ and 0.39 between 8℃ and 6℃. As a result of investigating the stress response according to the drop in water temperature, the concentration of SOD (Superoxide dismutase), cortisol, glucose, total Ig, AST (Aspartate) and ALT (Alanine aminotransferase) increased with decreasing of water temperature. This study would be useful for the management of temperature about cultured fish.

• 한국양식학회:학술대회논문집
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• 한국양식학회 2003년도 추계학술발표대회 논문요약집
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• pp.28-28
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• 2003

Viable interspecific hybrids between yellowtail flounder (Pleuronectes ferrugineus, Store.) and winter flounder (Pleuronectes americanus, Walbaum) were produced by artificial insemination of yellowtail flounder eggs with winter flounder sperm. However, mean fertilization rate, hatching success and early survival up to 3 weeks post hatch were significantly lower than those of parental pure cross controls (P<0.01). Overall, cytogenetic traits (karyological analysis and estimation of cellular DNA contents using flow cytometry) of hybrid flounder were intermediate between the two parental species. Microsatellite assay was used to distinguish the parental genomes in the hybrids; in most cases, one allele was specific to each of the parents. Morphometrics assessed by body proportions indicated that hybrids generally displayed a morphology intermediate between the maternal and paternal species. Interspecific hybrids exhibited abnormal and retarded gonad development in both sexes based on histological analysis of gonads from adult fish. The sterility of the hybrids presents a significant advantage for their use in aquaculture, as potential escapees would not be capable of reproducing in the wild and contaminating natural stocks.

• 한국초지조사료학회지
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• 제12권4호
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• pp.218-225
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• 1992

대관령지역에서 orehardgrass 17개 품종을 공시하 여 월동성지수와 상대경수출현율당 개체중에 의한 월동성의 품종간 차이를 비교함과 동시에 월동성검 정에 유효한 형질을 평가하고자 하였다. 1. 월동전 유식물체의 초세는 l번초의 개체중과 상대경수출현융당 개체중과는 유의한 부의 상관을 나타내었다 2. I번초의 개체중은 개체당경수,I경중,포장생존율, 출수율 및 출수경중과는 유의한 정상관이 인정되었다 3. I번초의 개체중은 월동성지수와는 5%수준, 상대 경수출현율당 개체중과는 1%수준의 유의한 정상관이 인정되었다. 4 .월동성지수는 포장생존율과 상대경수출현융당 개체중은 1경중 및 출수경중과 각각 1%수준의 정상 관이 인정되었다. 5 월동성 지수에 의하여 2품종군으로 분류할 수 있는데 월동성지수가 100이상인 품종에는 Hallmark, lna, Rancho, Amba, Filippa, Sparta, Hokuto, Kitam midori, Okamidori, Wasemidori, Shinyo, Potomac 그리고 Summer-green의 13개 품종이 포함되었고, 월동성지수가 100미만의 품종에는 Able, Juno, Napier 그리고 Jesper의 4개 품종이 포함되었다. 6. 상대경수출현융당 개체중에 의해서도 2 품종군 으로 분류할 수 있는데 상대경수출현율당 개체중이 l 1.0이 상의 품종에 는 Amba, Okamidori, Wasemidori 그리고 Summer-green의 4개 품종이 포함되었고, 100미만의 품종에는 Able, Hallmark, lna, Juno,Napier, Rancho, Filippa, Jesper, Sparta, Hokuto, K Kitamidori, Shinyo 그리고 Potomac의 13개 품종이 포함되였다 상대경수출현율당 개체중이 1.0이상으로 월동성이 높은 품종은 Amba, Okamidori, Wasemidori, Sum¬m$\varepsilon$r-gr$\varepsilon$en 의 4개 품종이었으며 이 들 품종들의 월 동 성지수는 100이상을 나타내였다. 7 .상대경수출현율당 개체중은 대관령지역(해발 8 800m)에서 월동성을 나타내는 유효한 생태적인 형질 이라고 생각되었다.