• 한국수산과학회지
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• 제49권5호
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• pp.612-619
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• 2016

In this study, we crossbred Epinephelus akaara and E. lanceolatus to produce a hybrid grouper with faster growth and adaptation to domestic aquaculture environments. The plasma cortisol and glucose levels and osmoregulation (stress response indicators) of the hybrid grouper, E. akaara ♀ × E. lanceolatus ♂, were investigated under several salinity levels (32, 24, 16, and 8 psu). The body lengths and weights of E. akaara (8.2 ± 0.1 cm, 8.3 ± 0.4 g) and the hybrid (8.6 ± 0.1 cm, 10.0 ± 0.4 g) were similar at the start of the experiment, but were significantly different at the end of the experiment. Juveniles of both E. akaara and the hybrid showed greater weight gain, specific growth, and feed conversion rate (FCR) under low salinity of 16 psu. Under the 8 psu treatment, the juvenile E. akaara all died, while the hybrid juveniles survived. Plasma cortisol levels were not affected by lower salinity in both species. The above results indicate that the hybrid is more tolerant of low salinity than is E. akaara, although both species exhibited higher growth and FCR at 16 psu, lower than the salinity of natural seawater. Thus, juveniles of both E. akaara and the hybrid can be more effectively cultured in brackish areas or waters with salinity lower than that of seawater.

• 한국수산과학회지
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• 제36권1호
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• pp.39-43
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• 2003

넙치의 생존, 성장 및 대사에 미치는 카드뮴의 만성적 독성을 파악하기 위하여 6주 동안 여러 가지 카드뮴 농도에 노출시켜 실험을 실시하였다. 넙치의 생존율은 카드뮴농도 980 ${\mu}g/L$에서 유의한 감소를 나타냈다. 넙치의 성장률과 사료효율은 카드뮴농도가 증가할수록 감소를 하여 210 ${\mu}g/L$ 이상의 농도에서는 대조구에 비하여 유의한 감소를 나타냈다. 넙치의 대사율은 카드뮴농도 90, 210, 450, 980 ${\mu}g/L$에서 대조구보다 각각 3.3, 18.3, 30.0, $50.1\%$가 저하하여 210${\mu}g/L$ 이상의 농도에서는 유의한 감소를 나타냈다.

• 한국토양비료학회지
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• 제42권5호
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• pp.323-329
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• 2009

This study was conducted to analyze growth responses of fast growing tree species(8 clones of hybrid poplars, Salix alba, Metasequoia glyptostroboides, Liriodendron tulipifera, Acer okamotoanum, and Quercus palustris), the chemical characteristics of soil and $NO_3-N$ concentration of groundwater in a plantation applied with liquid pig manure. Concentrations of nitrogen and phosphorous in the soil treated with liquid pig manure were higher than that of the soil treated without liquid pig manure. With the exception of S. alba, DBH(Diameter at Breast Height) growth of all the fast growing tree species treated with liquid pig manure was higher than that of the species treated without liquid pig manure. In liquid pig manure treatment group, P. euramericana 'Eco28' clone showed the best performance in height and DBH growth. Concentration of nitrogen in the leaf with liquid pig manure was higher than that of the leaf treated without liquid pig manure. Based on the $NO_3-N$ concentration of groundwater analyzed during the experimental period, there was no evidence that groundwater was polluted by the liquid pig manure applied at the plantation.

• ALGAE
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• 제34권2호
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• pp.153-162
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• 2019

Anthropogenic disturbances, including coastal habitat modification and climate change are threatening the stability of kelp beds, one of the most diverse and productive marine ecosystems. To test the effect of temperature and irradiance on the microscopic gametophyte and juvenile sporophyte stages of the rare kelp, Saccharina angustissima, from Casco Bay, Maine, USA, we carried out two sets of experiments using a temperature gradient table. The first set of experiments combined temperatures between $7-18^{\circ}C$ with irradiance at 20, 40, and $80{\mu}mol\;photons\;m^{-2}\;s^{-1}$. The second set combined temperatures of $3-13^{\circ}C$ with irradiance of 10, 100, and $200{\mu}mol\;photons\;m^{-2}\;s^{-1}$. Over two separate 4-week trials, in 2014 and again in 2015, we monitored gametogenesis, the early growth stages of the gametophytes, and early sporophyte development of this kelp. Gametophytes grew best at temperatures of $8-13^{\circ}C$ at the lowest irradiance of $10-{\mu}mol\;photons\;m^{-2}\;s^{-1}$. Light had a significant effect on both male and female gametophyte growth only at the higher temperatures. Temperatures of $8-15^{\circ}C$ and irradiance levels of $10-100{\mu}mol\;photons\;m^{-2}\;s^{-1}$ were conditions for the highest sporophyte growth. Sporophyte and male gametophyte growth was reduced at both temperature extremes-the hottest and coldest temperatures tested. S. angustissima is a unique kelp species known only from a very narrow geographic region along the coast of Maine, USA. The coupling of global warming with high light intensity effects might pose stress on the early life-history stages of this kelp, although, as an intertidal species, it could also be better adapted to temperature and light extremes than its subtidal counterpart, Saccharina latissima.

• 한국수산과학회지
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• 제52권1호
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• pp.43-48
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• 2019

This study was conducted to investigate the effect of extruded pellet (EP) size on the growth performance of olive flounder Paralichthys olivaceus at the juvenile (Exp-I; $62.2{\pm}0.05$), growing (Exp-II; $150{\pm}1$) and sub-adult (Exp-III; $299{\pm}1$) stages. In Exp-I (3, 4, 5 and 6 mm diets), Exp-II (4, 9, 11 and 13 mm diets) and Exp-III (9, 11, 13 and 16 mm diets), triplicate groups of fish were fed four EP diets of different pellet sizes. In Exp-I, larger pellet sizes were significantly better than the smallest pellet size (3 mm). In Exp-II, significantly improved feed and protein efficiency were observed with increasing pellet size. The feed conversion ratios of the fish fed the 4 and 9 mm diets were significantly lower than those of fish fed 11 and 13 mm diets. The dietary digestibility of protein and energy was higher in smaller EPs than in larger sizes. In Exp-III, the growth performance of fish was not affected by the pellet size. However, feed intake was significantly affected, increasing with increasing pellet size. Therefore, the optimum pellet sizes for olive flounder under the conditions in this study were 5 mm for 60-150 g fish and 9 mm for 150-500 g fish.

• 한국수산과학회지
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• 제34권2호
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• pp.131-136
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• 2001

양산시 내원사 계곡에 서식하는 다슬기 (Semisulcospira libertina libertina)를 대상으로 상대성장과 보육낭내 유생조성을 조사하였다. 조사한 다슬기의 총 개체수는 1,200마리였으며, 각고(SH), 각경 (SD), 전중 (TW), 육중 (MW) 및 각중 (SW) (평균$\pm$표준편차)은 각각 $15.96\pm3.41\;mm$, $7.82\pm1.38mm$, $0.55\pm0.31\;g$, $0.24\pm0.15g$, $0.39\pm0.23g$이었다. 각각의 상대성장식은 SD=0.3583 SH+2.1648 $(R^2=0.8391),\;TW=0.0005SH^{2.4853}\;(R^2=0.8391)$, $MW: 0.0005SH^{2.849}\;(R^2= 0.8391)\;SW=0,0004SH^{2.3798}\;(R^2=0.7057)$였다. 다슬기는 연중 보육낭내 발생중인 유생을 갖고 있었으며, 유생수는 봄$\cdot$여름에 감소하고 가을에 증가하는 경향을 보였다. 다슬기 암컷 1개체당 보육낭내의 평균 유생수는 11월에 396$\pm86$마리로 가장 많았으나, 7월에는 $91\pm86$33마리로 가장 적은 수를 나타냈다. 보육낭내 유생의 발달단계별 조성에 있어서 trochophore는 5월에 $66.7\%$, pre-veliger는 11월에 $70.7\%$, veliger는 2월에 $60.9\%$, juvenile은 1월에 $13.9\%$로 가장 높은 값을 보였다. 출산 전 단계인 juvenile의 빈도는 $3\~5$월, $8\~11$월에 감소하는 경향을 나타냈다. 이상의 조사결과에 따라, 다슬기의 출산성기는 $3\~5$월, $8\~10$월의 연 2회인 것으로 추정되었다.

• 한국수산과학회지
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• 제42권3호
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• pp.250-256
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• 2009

A 8-week feeding trial was conducted to investigate the effects of dietary supplementation of Kugija (Lycium chinense) on the growth and immunological response in juvenile Korean rockfish (Sebastes schlegeli). Six experimental diets were supplemented with Kugija at 0, 0.1, 0.5 1.0, 3.0 and 5.0% ($K_0,\;K_{0.1},\;Ko_{0.5},\;K_{1.0},\;K_{3.0},\;K_{5.0}$) on a dry-matter basis. After 2 weeks, triplicate groups of 30 fish initially averaging 3.36$\pm$0.2 g (mean$\pm$SD) were randomly distributed into the aquarium and were fed one of the experimental diets for 8 weeks. By the end of the 8-week feeding trial, fish fed the $K_{0.5}$ and $K_{1.0}$ diets exhibited a higher weight gain and specific growth rate than fish fed $K_0$ and $K_{0.1}$ diets (P<0.05). Feed efficiency of fish fed the $K_{0.5}$ diet showed significant higher value than that of fish fed the $K_0$, $K_{3.0}$ and $K_{5.0}$ diets (P<0.05). Hepatosomatic index of fish fed the $K_{0.5}$ diet was significantly higher than that of fish fed the $K_{0.1}$ and $K_{5.0}$ diets (P<0.05). Hematocrit of fish fed the $K_{0.5},\;K_{1.0}$ and $K_{5.0}$ diets was significantly higher than that of fish fed the $K_0$ diet (P<0.05). Glutamic oxaloacetic transaminase of fish fed the $K_{0.5},\;K_{1.0},\;K_{3.0}$ and $K_{5.0}$ diets was significantly lower than in fish fed the other diets (P<0.05). Glutamic pyruvic transaminase activity of fish fed the $K_{3.0}$ diet was significantly lower than those of fish fed the $K_0$ and $K_{0.1}$ diets (P<0.05). However, there was no significant difference in the activity of the transaminase in fish fed the $K_{0.5}\;K_{1.0},\;K_{3.0}$ and $K_{5.0}$ diets. Lysozyme activity of fish fed the $K_{0.5}$ and $K_{1.0}$ diets was significantly higher than that in fish fed the $K_0$ and $K_{0.1}$ diets (P<0.05). Respiratory burst activity of fish fed the $K_{3.0}$ diet was significantly higher than those of fish fed the $K_0$ and $K_{0.1}$ diets (P<0.05). However, there was no significant difference in respiratory burst activity of fish fed the $K_{0.5}\;K_{1.0},\;K_{3.0}$ and $K_{5.0}$ diets. Fish fed Kugija showed lower early mortality than fish fed a Kugija-free diet upon challenge with Vibrio ordalii. The results suggest that feeding of Kugija (Lycium chinense) enhances growth, non-specific immunity and disease resistance in juvenile Korean rockfish.

• 한국발생생물학회지:발생과생식
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• 제10권4호
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• pp.271-275
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• 2006

본 연구의 목적은 부화 후 67일 동안 대서양산 Haddock, Melanogrammus aeglefinus 치어의 초기성장을 조사하여, 본 종의 발생생물학과 양식 측면에서의 정보 제공하고자 한다. 전장성장은 $TL=3.5374e^{0.0536X}(r^2=0.8759$, TL은 전장이며, X는 부화 후 표본시일), 체중성장은 $BW=0.0002e^{0.1858X}(r^2=0.8671$, BW는 체중이며, X는 부화 후 표본시일)로 각 성장들은 지속적인 성장을 보였다. 체고와 가슴지느러미 길이는 연속적인 성장을 보여 체고성장은 $BD=0.3545e^{0.0778X}(r^2=0.9563$, BD는 체고이며, X는 부화 후 표본시일)였으며 가슴지느러미 길이성장은 $PL=0.0111e^{0.1591X}(r^2=0.9194$, PL은 가슴지느러미 길이이며, X는 부화 후 표본시일). 전장에 대한 체고의 상관관계식은 BD=0.2397X-0.5735($r^2=0.9957$, BD는 체고이며, X는 전장)이었으며 전장에 대한 가슴지느러미 길이의 상관관계식은 PL=0.1929X-1.3767($r^2=0.9882$, PL은 가슴지느러미 길이이며, X는 전장)이었다. 체고에 대한 가슴지느러미 길이성장은 PL=0.8117BD-0.9718($r^2=0.9814$, PL은 가슴지느러미 길이이며, BD는 체고)이었다. 체중에 대한 체고는 $BD=-9.4734X^2+19.046X+1.3672(r^2=0.9041$, BD는 체고이며, X는 체중)로, 체중에 대한 가슴지느러미 길이는 $PL=-6.379X^2+14.023X+0.3774(r^2=0.9494$, PL은 가슴지느러미 길이이며, X는 체중)이었다. 본 연구결과의 Haddock 치어 초기성장 특성은 Haddock 치어 사육에 도움이 될 것이다.

• 한국학교ㆍ지역보건교육학회지
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• 제15권2호
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• pp.23-38
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• 2014

Objectives: Since juveniles' unhealthy diets, and their problematic behavior resulting from drinking cause serious harm to those who are in a period of growth, we attempted to find out the relationship between juveniles' dietary habits and their drinking alcohol. Methods: The data was collected from 74,186 people in a 2012 web-based survey of Korean juveniles' health behavior, which was jointly conducted by the Ministry of Education, Science, and Technology, the Ministry of Health and Welfare, and the Korea Centers for Disease Control. This study conducted a logistic regression analysis using SPSS 18.0. Results: Juveniles who consume fast food at least once in a day have a significantly higher chance of binge drinking (OR=3.063, 95% CI=2.332~4.023), problematic drinking(OR=6.041, 95% CI=4.947~7.379) than those who don't. It also indicates that juveniles who don't eat breakfast have a significantly higher chance of binge drinking (OR=1.358, 95% CI=1.158~1.593), problematic drinking(OR=1.762 95% CI=1.548~2006) than those who eat breakfast every day. Conclusions: Irregular breakfast or a frequent intake of fast food causes problematic drinking, and binge drinking. Therefore, when planning programs for the prevention of juvenile drinking, it seems necessary to include education of healthy dietary habits.

• 한국양식학회지
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• 제11권2호
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• pp.159-166
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• 1998

참전복용으로 경제적인 배합사료를 개발하기 위해 이미 수행된 실험 결과를 바탕으로, 배합되는 원료의 조성비(7 종류)와 단가(사료원료의 단가:kg당 5,000원에서 800원대)를 달리하여 외국산 수입사료 및 천연먹이 (건조미역)와 그 효능을 비교하였다. 평균체중 120 mg의 참전복 치패를 선별하여 각 실험수조에 70마리씩 완전임의 배치하여 각 실험사료마다 3반복으로 4개월간 사육실험하였다. 사육 결과, 생존률은 71~90% 범위였으며, 미역 공급구가 71%로 가장 낮은 값을 보였다. 최종 평균체중, 증체율 가식부 중량, 체중에 대한 가식부 중량비, 평균 각장 및 각폭은 사료 단가가 5,000원대로 가장 비싼 사료와 건조 미역 공급구가 가장 낮은 값을 보여 타 실험구와 차이를 보였으며(P<0.05), 그 외 실험사료들은 서로 유의차가 인정되지 않았다.(P>0.05). 실험 종료시 가식부의 일반성분 중에서 수분과 회분은 실험구간에 서로 유의차가 없었으나(P>0.05), 단백질 함량은 사료 단가가 5,000원대인 사료가 가장 낮았으며, 지질함량은 건조 미역구가 0.73%로 가장 낮았다(P<0.05). 위와 같이 단가가 가장 비싼 사료구 외의 실험 배합사료는 외국 수입사료와 비교하였을 때 그 효능이 전혀 뒤지지 않은 것으로 보아, 사료의 단가는 kg당 1,000원 전후로 낮아질 수 있을 것으로 기대된다.