• Fisheries and Aquatic Sciences
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• 제24권12호
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• pp.400-405
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• 2021

In this study, the relationship between the growth of abalone and the presence of epibionts was investigated in abalone cultured in Goheung, Jeollanam-do, where there are severe problems high water temperatures and attachment. The experiment was conducted for eight months (May-December 2020), and 40 abalone were collected every month. Water temperature was at its highest at a range of 13.5℃-26.6℃ and dissolved oxygen levels were at their lowest at a range of 4.0-10.2 ㎍/L in August. The shell height (mm) of abalone grew to 117.7% (81.8 ± 1.9 mm) in cultures where epibionts were removed (ER) and 111% (77.4 ± 3.3 mm) where they were not (non-epibionts, NER). Their total weight (TW) and body weight increased significantly and steadily with ER, whereas the TW increased sharply after August with NER. In the condition index, no significant difference was observed between ER and NER. The monthly proportion of epibionts increased significantly in July, accounting for the value of 69.9% reached in December.

• Fisheries and Aquatic Sciences
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• 제24권7호
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• pp.235-242
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• 2021

The present study investigated the critical thermal maxima (CT_max) of red-spotted grouper, Epinephelus akaara under different acclimation temperatures (T_acc). Fish were acclimated at 24℃, 28℃, and 32℃ water temperature for 2 weeks. Water temperature was increased at a rate of 1℃/h and CT_max level was measured following the critical thermal methodology (Paladino et al., 1980). The results showed that CT_max values of E. akaara were 35.61℃, 36.83℃, and 37.65℃ for fish acclimated at 24℃, 28℃, and 32℃, respectively. The acclimation response ratio (ARR) was 0.26. The CT_max values were significantly correlated with body size. Collectively, it is said that the CT_max value of red-spotted grouper can be affected by different adaptation temperature (24℃, 28℃, and 32℃) and the fish acclimated to a higher temperature has a higher CT_max level. Besides, the CT_max value of 35.61℃-37.65℃ indicating the upper thermal tolerance limit for E. akaara under different T_acc (24℃, 28℃, and 32℃). Understanding the thermal tolerance of E. akaara is of ecological importance in the conservation of this species.

• 한국자기공명학회논문지
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• 제26권4호
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• pp.46-50
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• 2022

Antifreeze proteins (AFPs) bind to the ice crystals and then are able to inhibit the freezing of body fluid at subzero temperatures. Type III AFPs are categorized into three subgroups, QAE1, QAE2, and SP isoforms, based on differences in their isoelectric points. We prepared the QAE2 (AFP11) and SP (AFP6) isoforms of the notched-fin eelpout AFP and their mutant constructs and determined their temperature gradients of amide proton chemical shifts (𝚫δ/𝚫T) using NMR. The nfeAFP11 (QAE2) has the distinct 𝚫δ/𝚫T pattern of the first 3₁₀ helix compared to the QAE1 isoforms. The nfeAFP6 (SP) has the deviated 𝚫δ/𝚫T values of many residues, indicating its backbone conformational distortion. The study suggests the distortion in the H-bonding interactions and backbone conformation that is important for TH activities.

• 대한화학회지
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• 제66권4호
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• pp.278-283
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• 2022

Kirkwood의 방법을 이용하여 단순입방격자나 체심입방격자와 같이 두개의 동등한 상호침투 격자로 구성된 이성분 격자 용액의 자유에너지를 절대온도 역수의 10차항까지 계산하였다. 이를 이용하여 이성분 격자 용액에 대한 액체-액체 공존 곡선과 임계용액온도를 계산하여 분자들의 논랜덤 혼합 효과를 정량적으로 살펴보았다. 그리고 단순입방격자 이성분용액의 공존 곡선을 Monte-Carlo 컴퓨터 모사의 결과와 비교하여 잘 일치하는 것을 알 수 있었다.

• 한국수산과학회지
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• 제56권1호
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• pp.44-53
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• 2023

In this study, the morphological development and early life cycle of larvae and juvenile Rhinogobius brunneus found in Wicheon, Nakdong River, Korea, were investigated. The fertilized eggs were 2.20×0.68 mm (long×short) in diameter. The eggs began hatching approximately 104 h after fertilization at water temperatures of 17.3-20.5℃ (mean 18.9±1.6℃). The newly hatched yolk-sac larvae were 3.71±0.06 mm in total length (TL), with an unopened anus. Three days after hatching, the preflexion larvae were 4.37±0.16 mm in TL with yolk absorption. Twenty days after hatching, the flexion larvae were 6.50±0.22 mm in TL and the tip of the notochord was bent upward. Twenty-seven days after hatching, the postflexion larvae were 11.8±0.63 mm in TL, and the tip of the urostyle was bent at 45°. Forty days after hatching, individuals measured 18.5±0.93 mm in TL and were considered as juveniles as the number of fins became constant for each part. All the postflexion larvae had detached fins. Additionally, the melanophore was observed to be distributed on the head, centrum of the body, and dorsal fin, and there was a difference in the morphology from the water stream.

• 한국산학기술학회논문지
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• 제18권1호
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• pp.135-140
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• 2017

본 연구는 포유기간 중 이복자돈과의 합사가 모돈과 자돈의 체표면 온도 변화에 미치는 영향을 조사하기 위하여 실시하였다. 임신모돈 12두를 공시하여 6두는 개별 분만펜에 위치시켜 분만 후 이유시까지 복당 사육을 유지하였으며(대조구), 6두는 중간 칸막이의 제거가 가능한 가변형 분만펜에서 3복이 한 펜이 되도록 분만 11일차에 칸막이를 제거하여 이유시까지 유지하였다(처리구). 합사 30분 후에 열화상카메라를 이용하여 모돈 및 자돈의 체표면 온도를 측정하였다. 분만 후 포유모돈의 평균 체표면 온도는 처리구에서 $37.1^{\circ}C$로 대조구의 $36.3^{\circ}C$보다 유의적으로 높은 것으로 나타났고 (p<0.05), 최고온도에서는 두 처리간 유의적인 차이가 없었다. 이와 대조적으로, 포유 자돈의 평균 체표면 온도는 포유기 합사에 의해 유의적으로 감소하였으며(대조구 37.5, 처리구 $36.0^{\circ}C$; p<0.01). 최고온도에서 또한 대조구와 처리구에서 각각 $39.4^{\circ}C$와 $39.1^{\circ}C$로 유의적인 차이는 아니지만 대조구에서 낮은 경향으로 관찰되었다(p=0.079). 결론적으로 포유기간 중에 이복자돈과의 합사에 의해 모돈의 체표면 온도는 상승되지만, 자돈의 체표면 온도는 감소하는 것으로 관찰되었다. 더 나아가 체표면 온도와 심부온도와의 상관관계를 구명하고, 합사에 의한 모돈 및 자돈의 생리적 변화에 대한 연구가 필요할 것으로 사료된다.

• Asian-Australasian Journal of Animal Sciences
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• 제27권5호
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• pp.690-699
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• 2014

Three feeding trials were conducted to evaluate the effects of feeding rate and water temperature on growth and body composition of juvenile Korean rockfish, Sebastes schlegeli rearing at 3 different water temperatures. A total of 270 fish (each experiment) individual body weight (BW) averaging $16{\pm}0.3g$ ($mean{\pm}SD$) were fed a commercial diet for 4 wk at $16^{\circ}C$, $20^{\circ}C$, and $24^{\circ}C$. At each temperature, triplicate tanks were assigned to one of 6 feeding rates: 1.5%, 2.5%, 2.8%, 3.1%, 3.4%, and satiation (3.7% BW/d) at $16^{\circ}C$, 1.9%, 2.9%, 3.2%, 3.5%, 3.8% and satiation (4.1% BW/d) at $20^{\circ}C$ and 1.7%, 2.7%, 3.0%, 3.3%, 3.6%, and satiation (3.9% BW/d) at $24^{\circ}C$ water temperature. Weight gains of fish in satiation and 3.4% groups at $16^{\circ}C$, in satiation and 3.8% groups at $20^{\circ}C$ and in satiation and 3.6% groups at $24^{\circ}C$ were significantly higher than those of fish in the other treatments (p<0.05). A broken line regression analysis of weight gain indicated that optimum feeding rates of juvenile Korean rockfish were 3.41% at $16^{\circ}C$, 3.75% at $20^{\circ}C$ and 3.34% at $24^{\circ}C$ water temperature. Results of the present study indicate that the optimum feeding rate could be >3.1% but <3.41% at $16^{\circ}C$, >3.5% but <3.75% at $20^{\circ}C$ and >3.0% but <3.34% at $24^{\circ}C$. As we expected results suggest that fish performed better at $20^{\circ}C$ than $16^{\circ}C$ or $24^{\circ}C$ water temperature and the optimum feeding rate could be 3.1% BW/d to 3.7% BW/d in 16 g of juvenile Korean rockfish.

• 한국식품영양과학회지
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• 제39권6호
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• pp.820-825
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• 2010

본 연구에서는 비만과 관련된 요소 중 하나인 장내 균총을 개선하고자, 식이섬유소가 풍부하고 저칼로리인 담자균류 추출물을 이용하여 in vitro 상에서 비만 관련 장내 미생물에 대한 항균활성을 조사하였다. 항균성 담자 균류 소재 탐색결과 석이버섯 자실체와 운지버섯 균사체의 추출물을 선발하였고, 선발된 담자균류 소재 추출물의 특성을 분석한 결과 열에 대단히 안정하였고, pH에도 비교적 안정한 것으로 나타났다. 또한 rat을 이용한 동물실험에서 석이버섯 80% 에탄올 추출물 투여군이 고지방식이만 투여한 군에 비하여, 장내 균총에서 Bifidobacterium spp.가 증가되었고, Clostridium spp.와 Eubacterium spp.는 감소된 것으로 나타났다. 석이버섯과 운지버섯 추출물이 첨가된 기능성 음료를 제조하고자 관능평가를 실시한 결과, 운지버섯 균사체 배양액에 석이버섯 추출물을 3% 첨가한 실험구가 가장 좋은 평가를 받았다. 이러한 결과를 토대로 석이버섯과 운지버섯 추출물이 장내 균총 개선을 위한 기능성 식품소재로 활용될 수 있을 것으로 생각된다.

• 한국임상수의학회지
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• 제17권1호
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• pp.93-101
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• 2000

This study was carried out to investigate the epidemiological prevalence of diseases from birth to weaning in 268 Koeran native calves which was delivered from three stock farm in Chonbuk area. We examined body weight gain, incidence rate of diseases and mortality rate in relation to age, season, environmental temperature and rearing management conditions for one year. The results of this experiment were as follows: Birth weight and body weight gain of Korean native calves born of primiparae were lower than those of multiparae. Body weight gain of diseased calves was lower than normal calves. Of 268 delivered calves, 242 calves(90.3%) were affected with gastronistestinal and/or respiratory diseases. The prevalence of the diseases were gastronitestinal disease(54.1%), gastronitestinal and respiratory disease(21.6%), and respiratory disease(14.5%). Of 242 diseased calves, 33 calves(13.6%) were occurred gastronitestinal disease and respiratory disease at different time respectively. Of 268 delivered calves, 126 calves were died(47%). The prevalence of the death were gastronitestinal disease(31.4%), gastronitestinal and respiratory disease(14.5%), and respiratory disease(1.1%). 81% of the diseases and 76.2% of the death were occurred in winter and a change of season(December to May). 59.1% of the diseases and 52.4% of the death were occurred at atmospheric temperatures below 1$0^{\circ}C$. 91.7% of the diseased calves and 96.8% of the dead calves were born of primiparae. 77.2% of the gastronitestinal disease were occurred within 2 weeks old, and the incidence was decreased with increasing age. Whereas the incidence of respiratory disease was incidence with ageing, and 69.2% of the respiratory disease were occurred between 2 weeks and 5 weeks old. And 62% of the gastronitestinal and respiratory disease wre occurred between 1 week and 3 weeks old. 65.1% of the dead calves were died within 2 weeks old. The morbidity and population mortality rate in each farm stock were 56.5%-104.9%, and 14.5%-64.2%, respectively.

• 한국버섯학회지
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• 제15권4호
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• pp.190-194
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• 2017

생육이 균일하고 다수성인 산느타리버섯 신품종 '산타리'의 주요특성은 다음과 같다. $26{\sim}29^{\circ}C$이고 버섯발생온도는 $22^{\circ}C$, 버섯생육온도 $18^{\circ}C$로 '호산'과 유사하며, 발생형은 다발형태를 나타내었다. 병재배시 배양기간은 28일, 초발이 소요일수는 3일, 생육일수는 3일로 총재배기간은 34일이 소요되었다. 갓크기는 35.9 mm이며, 갓색도(L)는 53.7로 회갈색을 나타내었고, 대는 직경 10.1 mm, 길이 79.7 mm로 '호산' 에 비하여 굵고 긴형태이며, 대색택은 L=93으로 백색을 나타내었다. 수량은 생산력 검정시 1,100 ml병에서 172 g을 나타내었으며, 농가실증재배시 A(여주1) 120.8 g/900 ml, B (여주2) 165.2 g/900 ml, C(용인) 141.7 g/900 ml으로 대조구 대비 24% 이상 증수되었다. 대의 물리성은 탄력성, 응집성, 씹읍성, 깨집성이 각각 87%, 82%, 193 g, 16.8 kg을 나타났다. DNA다형성을 비교 분석한 결과 URP3, URP10, URP12의 primer에서 교배 모본인 '호산'과 'GMPO20404'의 DNA의 밴드가 혼합되어 있었으며 품종간, 균주간의 밴드 차이가 있었다. 저장 기간에 따른 신선도는 저온저장시 7, 상온보관시 6 을 나타내어 대조품종인 '호산' 보다 상온보관시 신선도가 우수하였다.