• 한국수산과학회지
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• 제54권1호
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• pp.118-123
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• 2021

This study was conducted to evaluate plant proteins as a replacement for a fishmeal diet in the rearing of coho salmon Oncorhynchus kisutch. Twelve groups of 20 fish averaging 34.0±0.62 g were randomly distributed into 12 rectangular tanks (250 L). Four experimental diets included a control diet containing 60% fishmeal (Control), and three other diets that replaced 20% of fishmeal with soy protein concentrate (SPC), fermented soybean protein concentrate (F-SPC), and enzyme-processed soy protein concentrate (E-SPC). At the end of the feeding trial, fish that were fed Control, SPC and E-SPC diets showed significantly higher weight gain, specific growth rate, feed efficiency, and protein efficiency ratio than those that were fed F-SPC diet. However, there were no significant differences among the fish that were fed Control, SPC, and E-SPC diets. No significant differences were observed in crude protein, crude lipid, and ash of whole body among the fish that were fed all the diets. Therefore, these results indicated that 20% of fishmeal could be replaced by E-SPC or SPC without any adverse effects on the growth performance of coho salmon.

• 한국수산과학회지
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• 제54권3호
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• pp.298-310
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• 2021

Freshwater eel Anguilla japonica is a commercially important species in East Asia. However, given the continuously decreasing resources due to many problems as climate change, habitat destruction and overfishing, mass seed production is crucial. In particular, the eel larvae present a unique life history, spending prolonged periods in the Pacific Ocean. Therefore, finding suitable feed that lasts through the long larval stages is rather difficult. In the present study, we histologically observed the development of digestive organs for 50 days after hatching (DAH). The endogenous reserves were completely absorbed at 7 DAH, and the first exogenous feeding started thereafter. The teeth appeared at 4 DAH and dramatically changed from needle-like to broad-based types by 50 DAH. The intestine remained as straight gut until 50 DAH. The intestinal cilia appeared first at 6 DAH and their density continuously increased thereafter. Interestingly, goblet cells appeared in the intestine, but not in the esophagus, where these cells are commonly observed in other teleosts. In addition, high amounts of eosinophil substances, assumed to be zymogen granules, accumulated in the pancreas, suggesting a specific digestive strategy of this species. Overall, these observations largely update the previous reports and can be useful to improve A. japonica seed production.

• 한국어류학회지
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• 제33권4호
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• pp.273-277
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• 2021

한국 서해에 출현하는 용가자미 (Cleisthenes pinetorum)의 섭식습성에 대한 연구를 위해 2019년 1월부터 12월까지 자망어선에서 어획된 360개체(전장 21.7~48.1 cm) 위내용물을 분석하였다. 용가자미의 주 먹이생물은 거미불가사리류와 어류로 나타났고, 이외에도 새우류, 난바다곤쟁이류, 단각류, 게류 등을 소량 섭식하였다. 이러한 연구의 결과는 고리연안에서 보고된 용가자미의 섭이 습성 결과와 차이를 보였다(Huh and Baeck, 2003). 용가자미가 성장함에 따라 거미불가사리류의 비율이 감소하고 어류의 비율이 증가하였고, 용가자미 전장이 증가하면서 개체수와 습중량은 증가하는 경향을 보였다.

• Journal of Animal Science and Technology
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• 제64권3호
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• pp.462-470
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• 2022

The addition of dietary proteases (PRO) to weaner diets hydrolyzes soybean-based anti-nutritive factors and improves weaned pig's dietary digestibility and growth performance. Therefore, this study explores the effects of PRO in a lower crude protein (CP) level diet than that in a commercial diet on the growth performance, nutrient digestibility, and intestinal morphology of weaned pigs. A total of 90 weaned pigs were randomly assigned to 3 dietary treatments with 6 pigs per pen and 5 replicated pens per treatment using a randomized complete block design (block = body weight [BW]): 1) a commercial weaner diet as a positive control (PC; phase1 CP = 23.71%; phase2 CP: 22.36%), 2) lower CP diet than PC as a negative control (NC; 0.61% less CP than PC), and 3) an NC diet with 0.02% PRO. Pigs fed PC and PRO had higher (p < 0.05) final BW, average daily gain, and/or gain to feed ratio for the first three weeks and the overall experimental period than NC. The PC and PRO groups had greater (p < 0.05) apparent ileal digestibility of dry matter, CP, and energy than the NC group. Moreover, pigs fed PC and PRO increased (p < 0.05) apparent total tract digestibility of CP compared with those fed NC. In addition, the PRO group had a higher number of goblet cells than the PC and NC groups. However, pig fed PC and PRO increased (p < 0.05) villus height and height to crypt depth ratio in the ileum compared with those fed NC. In conclusion, PRO supplementation in a commercial weaner diet with low CP levels improves growth rate and nutrient digestibility by modulating the intestinal morphology of weaned pigs.

• 한국수산과학회지
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• 제56권4호
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• pp.541-548
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• 2023

Behavior serves as an important indicator of the effects of environmental stressors on organisms. In this study, one-year-old abalone Haliotis discus hannai (15.1±0.8 mm) were used and each 0.34 m2 tank was stocked with 100, 150, 200, 250, and 300 juvenile abalone. After 328 days, we found that the low stocking density treatment showed significantly higher growth, whereas the high stocking density treatment showed significantly lower growth. In addition, abalone showed a lower rate of movement, distance moved, and velocity at higher stocking densities, but only velocity differed significantly. In contrast, In the Supplied the feed tanks significant difference between the moving distance and velocity. When the two groups of different sizes were mixed in tank, the rate of movement, distance moned, and velocity showed significant differences between differently-sized indivisuals. Our study indicates that breeding abalone at high densities has a negative effect on their growth and survival, which is thought to primarily be caused by spatial competition, and secondarily by differences in body size, ultimately affecting growth and productivity.

• 한국초지학회:학술대회논문집
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• 한국초지조사료학회 2002년도 창립 30주년 International Symposium
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• pp.103-127
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• 2002

독일에서 초지를 근거로 한 가축경영의 중요한 문제는 목초보다는 옥수수나 곡류로 아주 쉽게 얻어질 수 있는 사료인 고에너지 농후사료가 필수적인 고능력우의 사육에 있다. 그러므로 우유생산은 초지지역에서 사료작물 지역으로 이동하는 추세이다. 아마 미래에는 우유생산은 초지지역에서 사료작물 지역으로 이동하는 추세이다. 아마 미래에는 우유생산에 있어서 농후사료에 의한 과잉영양분은 정부에 의해 제약을 받게 될 것이며, 발생되는 문제는 가장 좋은 초지를 이용하고, 최적의 사일리지 및 분료이용 기술을 이용하므로 해결될 수 있다. 지속적인 조사료 생산의 가장 중요한 단계는 특히, 사일리지 목초지에서 일반적인 보파기술을 포함한 초지관리에 있다. Hessian 초지의 약 40% 정도가 초지이용을 유지하기 위하여 그리고 자연자원을 보호하기 위하여 농업-환경 프로그램들(agri-environmental programs)로 관리를 받고 있다. 선택적인 조치들이 자연 및 산림보존에 대한 특별한 문제들을 해결하기 위하여 수행되어지고 있다.

• 한국프랜차이즈경영연구
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• 제7권2호
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• pp.5-14
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• 2016

Purpose - Competitive industry structure and recent economic depression challenge a survival of Korean small- and medium-sized food franchising companies (SMFCs), albeit the explosive growth of the Korean food service industry for last few decades. Against this backdrop, it examines how these SMFCs overcome liabilities of smallness and resource scarcity to strengthen competitive advantage in the market. To tackle this, in this article we focus on corporate entrepreneurship and human resources as a knowledge-based asset for these SMFCs. Furthermore, the ratio of employee turnover is high in SMFCs. We view that such brain-drain may result in poor performance of the Korean SMFCs. As such, we pay attention to the role of organizational commitment to an organization as a solution for enhancing individual-level employees' loyalty toward their organization. Research design, data, and methodology - Our research question is to what extent corporate entrepreneurship (i.e., innovative organizational culture, organizational autonomy, and administrative innovation) affects an individual-level attitude toward the organization and, in turn, employee creativity and satisfaction in the Korean SMFCs context. We collected data from employees in SMFCs for three months. A total of 126 valid questionnaires were collected, and analyzed the data using partial least squares path modeling. Results - The reliable and valid measurement model feed into testing the structural model. Our findings suggest that innovative organizational culture and organizational autonomy positively affect employee commitment. Particularly, organizational autonomy has a greater effect than innovative culture on employee commitment. However, the relationship between administrative innovation and employee commitment is not significant. We also find that employee commitment positively affects both employee creativity and satisfaction. Conclusions - Our contribution to the existing franchising business and management literature is twofold. First, the conceptual model includes three antecedents in the organizational entrepreneurship dimension to organizational commitment. Second, we conceptualize organizational commitment as employee commitment, and validate its impact on employee creativity and job satisfaction at an individual performance level. Overall, this article suggests that it is critically important for the Korean SMFCs to develop corporate entrepreneurship in order to facilitate employees' positive attitudes toward their organizations.

• 한국초지조사료학회지
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• 제43권3호
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• pp.156-161
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• 2023

This study was conducted to determine the appropriate seeding dates by verifying the difference in winter survival and productivity of alfalfa according to fall sowing dates in the central area of South Korea. The experiment was conducted for 2 years (2020 and 2021) at the field in the Department of Animal Resources Development, NIAS located in Cheonan. Sowing dates started from September 18 to November 8 with 10 days of intervals during 2020 and 2021; SO1 (September 18), SO2 (September 28), SO3 (October 8), SO4 (October 18), SO5 (October 28), and SO6 (November 8). After sowing, the winter survival rate was measured in the spring of the following year, and the dry matter yield was measured by harvesting at 10% flowering and harvesting five times a year. SO6 failed to winter survival, and SO5 also had a lower winter survival rate than SO1~4 (p<0.05). The average annual dry matter yield of alfalfa linearly decreased with delaying sowing dates (p<0.05). The feed value did not differ in the same year by delaying the sowing date in the same year. These results suggest that sowing date should be started before October 18 to increase winter survival and productivity of alfalfa in the central area of South Korea.

• 한국환경과학회지
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• 제32권12호
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• pp.965-972
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• 2023

As the world population growth and economy develops, the importance of eco-friendly organic waste resource treatment and up-cycling increases. Black soldier fly (BSF) (Hermetia illucens) treats organic waste resources that allows it to be recycled as a feed resource. In this study, we analyzed the nutrients composition, amino acid, and fatty acids of BSF larvae fed three agricultural by-products, namely apple pomace, mandarin waste, and oriental melon waste (mainly generated in South Korea). The highest BSF larvae crude protein and amino acid content was obtained in those fed mandarin waste compared with the other two diets (apple pomace and oriental melon waste). BSF larvae fed apple pomace had the highest crude fat, fatty acid, and lauric acid content compared with the other BSF larvae. Furthermore, all crude protein and fat content of BSF larvae fed the three agricultural by-products exceed that of the original agricultural by-products.

• 신재생에너지
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• 제19권4호
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• pp.35-45
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• 2023

Global efforts are focused on achieving carbon neutrality due to the increases in the levels of greenhouse gases. Moreover, the greenhouse gases generated from the disposal of municipal solid waste (MSW) are the primary sources of emissions in South Korea. In this study, we conducted the biological conversion of syngas (CO, H₂, and CO₂) generated from MSW gasification. The MSW-derived syngas was used as a feed source for cultivating Eubacterium limosum KIST612, and pressurization was employed to enhance gas solubility in culture broth. However, the pH of the medium decreased owing to the pressurization because of the CO₂ in the syngas and the cultivation-associated organic acid production. The replacement of conventional HEPES buffer with a phosphate buffer led to an approximately 2.5-fold increase in acetic acid concentration. Furthermore, compared with the control group, the pressurized reactor exhibited a maximum 8.28-fold increase in the CO consumption rate and a 3.8-fold increase in the H2 consumption rate.