• Asian-Australasian Journal of Animal Sciences
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• v.18 no.7
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• pp.973-979
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• 2005

The present study was planned to examine the effect of different feeding regimens on milk urea concentration and milk protein concentration. The objectives are to describe the diurnal variations of milk urea (MU) concentration and to predict plasma urea (PU) concentration from MU concentration. Six lactating Murrah buffaloes were distributed in two groups and were fed two different diets in a crossover design. The diets consisted of leguminous crops as diet 1 (berseem (Trifolium alexandrinum)+concentrate mixture 1+wheat straw)) and non-leguminous crops as diet 2 (oats (Avana sativa)+concentrate mixture 2+wheat straw). All the diets were isocaloric and isonitrogenous. Each diet was fed to the animals for a period of 28 days, followed by a 10 day gap to obviate the carry over effect of the previous diet and then a switch over to the other diet. Digestibility trials were conducted on the last 7 days of each feeding period. Milk samples were collected on day 3, 7, 10, 14, 17, 21, 24 and 28 of the feeding period and blood samples were collected on the same day at morning within 30 minutes after morning milking. The average milk urea (MU) values (mg/dl) differed significantly (p<0.01) and were 44.83${\pm}$0.62 and 42.53${\pm}$0.73, respectively, for diets 1 and 2. Milk urea concentrations (mg/dl) also varied (p 0.01) among the days of feeding period, but were stabilized after 10th day of feeding period. In contrast, diets and days of feeding period had no significant effect on percent milk protein. Plasma urea concentration showed a significant (p<0.01) positive correlation (r = 0.93) with MU concentration. To predict the PU from MU the following equation was developed 'PU = 10.67${\pm}$0.76${\times}$MU (mg/dl) with $R^2$ = 0.87'. A clear diurnal variation of MU was found with lowered morning value (42.04${\pm}$0.68 mg/dl) than the evening value (45.32${\pm}$0.66 mg/dl). Present findings suggested that MU or PU concentration could be used as an indicator to monitor the feeding strategy. Plasma urea can be predicted from MU, whenever interpretation of milk urea data required consideration of diurnal variation.

• Journal of the Korean Applied Science and Technology
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• v.38 no.1
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• pp.241-262
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• 2021

This paper reviewed the necessity of a information and communication technology (ICT)-based smart livestock system as a development strategy for the animal life industry in the future. It also predicted the trends of livestock and animal food until 2050, 30 years later. Worldwide, livestock raising and consumption of animal food are rapidly changing in response to population growth, aging, reduction of agriculture population, urbanization, and income growth. Climate change can change the environment and livestock's productivity and reproductive efficiencies. Livestock production can lead to increased greenhouse gas emissions, land degradation, water pollution, animal welfare, and human health problems. To solve these issues, there is a need for a preemptive future response strategy to respond to climate change, improve productivity, animal welfare, and nutritional quality of animal foods, and prevent animal diseases using ICT-based smart livestock system fused with the 4th industrial revolution in various aspects of the animal life industry. The animal life industry of the future needs to integrate automation to improve sustainability and production efficiency. In the digital age, intelligent precision animal feeding with IoT (internet of things) and big data, ICT-based smart livestock system can collect, process, and analyze data from various sources in the animal life industry. It is composed of a digital system that can precisely remote control environmental parameters inside and outside the animal husbandry. The ICT-based smart livestock system can also be used for monitoring animal behavior and welfare, and feeding management of livestock using sensing technology for remote control through the Internet and mobile phones. It can be helpful in the collection, storage, retrieval, and dissemination of a wide range of information that farmers need. It can provide new information services to farmers.

• Korean Journal of Ichthyology
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• v.35 no.4
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• pp.305-312
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• 2023

Diet composition and feeding strategy of the largehead hairtail, Trichiurus japonicas were studied using 375 specimens collected by purse seine, set net fisheries and lure fishing from February 2021 to January 2022 in the southern sea of Korea. The anal length (AL) of these specimens was from 3.4~49.0 cm. T. japonicus fed majorly on Fishes (especially Engraulis japonicus) based on ranking index (%RI=99.3). Fishes were the main prey items for all size classes. T. japonicas also showed size-related dietary shift from E. japonicus to T. japonicus, Larimichthys polyactis and Engraulidae. Fishes were the main prey items for all seasons. The main fish prey during spring and summer was E. japonicus, but in the autumn and winter, the E. japonicus portion decreased, and T. japonicus, L. polyactis, and Engraulidae portion increased. T. japonicus were specialized feeders with E. japonicus as their dominant prey.

• Korean Journal of Ichthyology
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• v.23 no.2
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• pp.163-167
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• 2011

The feeding habits of Coilia nasus were studied using 107 specimens collected from January to December 2005 in the coastal waters off Gori, Korea. The size of C. nasus ranged from 8.4 to 29.5 cm in standard length (SL). C. nasus was a carnivore that mainly consumed shrimps and copepods. Its diet also included small quantities of amphipods, euphausiids and chaetognaths. The feeding strategy graphical method reveled than C. nasus was specialized feeder and showed narrow niche width. Both small and large size class of C. nasus mainly consumed shrimps and copepods, and did not showed significant size-related changes in feeding habits. However, the mean number and weight of preys per stomach was higher than large size class than small size class.

• Korean Journal of Ichthyology
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• v.36 no.1
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• pp.77-83
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• 2024

The feeding habits of shotted halibut, Eopsetta grigorjewi, were studied by examining the stomach contents of 419 individuals. We collected E. grigorjewi samples using offshore gill net and bottom trawl in West Sea of Korea from January to December 2019. The specimens ranged in total length (TL) from 22.5 to 50.3 cm. The main prey organisms were Macrura and Pisces, while Brachyura, Ophiuroidea, Littorinimorpha and Paguridea were found small amounts. E. grigorjewi fed on Macrura in summer and autumn, and mainly fed on Pisces in winter and spring. Smaller individuals (<30 cm TL) consumed Macrura such as Crangon hakodatei. The proportion of these prey items decreased with increasing Pisces such as Ammodytes personatus and Engraulis japonicus. The feeding strategy of E. grigorjewi is estimated to maintain prey individual as they grow, but increase their prey weight.

• Biotechnology and Bioprocess Engineering:BBE
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• v.5 no.4
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• pp.275-287
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• 2000

Fermentation strategies for recombinant protein production in Pichia pastoris have been investigated and are reviewed here. Characteristics of the expression system, such as phenotypes and carbon utilization, are summarized. Recently reported results such as growth model establishment, app58lication of a methanol sensor, optimization of substrate feeding strategy, DOstat controller design, mixed feed technology, and perfusion and continuous culture are discussed in detail.

• Biotechnology and Bioprocess Engineering:BBE
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• v.7 no.1
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• pp.43-51
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• 2002

The cloning and expression of $\beta-glucosidase$ II, encoded by the gene ${\beta}glu2$, from thermotolerant yeast Pichia etchellsii into Escherichia coli is described. Cloning of the 7.3 kb BamHI/SalI yeast insert containing ${\beta}glu2$ in pUC18, which allowed for reverse orientation of the insert, resulted in better enzyme expression. Transformation of this plasmid into E. coli JM109 resulted in accumulation of the enzyme in periplasmic space. At $50^{\circ}C$, the highest hydrolytic activity of 1686 IU/g protein was obtained on sophorose. Batch and fed-batch techniques were employed for enzyme production in a 14 L bioreactor. Exponential feeding rates were determined from mass balance equations and these were employed to control specific growth rate and in turn maximize cell growth and enzyme production. Media optimization coupled with this strategy resulted in increased enzyme units of 1.2 kU/L at a stabilized growth rate of $0.14\;h^{-l}$. Increased enzyme production in bioreactor was accompanied by formation of inclusion bodies.

• Korean Journal of Organic Agriculture
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• v.29 no.1
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• pp.137-148
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• 2021

The present study investigated the effect of average daily gain (ADG) on carcass traits of Hanwoo steers. A total of 233 heads of Hanwoo steer slaughtered from 2017 to 2020 were employed in the analysis. Their body weight profiles during feedlot and carcass traits were used. The entire feedlot period is split into two periods. ADG during the first period (ADG1) was then defined as an independent variable in statistical analysis. In the meantime, it was examined that how the cutoff month for the period split altered the significance of the effect of ADG1 on carcass traits. Subsequently, steers were assigned to two groups (High vs. Low) based on the median of total ADG1, and we compared the carcass traits of each group using a linear mixed model. ADG1 during 10 to 23 months showed a significant effect on all carcass traits except the marbling score. ADG1 significantly influenced carcass weight and eye muscle area of Hanwoo steers. And it was found that greater ADG1 could get greater carcass weight and eye muscle area (p<0.001). The result of this study provides preliminary information for the target month in the calculation of ADG1 mostly influencing carcass performance, and feeding strategy of Hanwoo steer in terms of sustainability.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.5
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• pp.655-667
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• 2001

This experiment was conducted to investigate the effect of feeding a low CP diet supplemented with synthetic amino acids on performance, nutrient utilization and carcass characteristics of finishing pigs fed under a three-phase feeding regimen. Ninety-six finishing pigs (Landrace$\times$Large White$\times$Duroc), $55.75kg{\pm}0.65$ of initial body weight, were blocked by weight and sex and allotted to four dietary treatments in a randomized block design. There were six pens per treatment and four pigs per pen. Pigs were fed a 16%-14%-12% CP (for phase I-II-III, respectively), sequence of diets. Dietary treatments were 1) Control, 2) Con+L (a sequence of diets reduced in CP by l percentage unit with lysine (L) supplementation, 3) Con+LMT (a sequence of diets reduced in CP by 2 percentage unit with LYS, methionine (MET) and threonine (THE) supplementation) and 4) Con+LMTT (a sequence of diets reduced in CP by 3 percentage unit with LYS, MET, THR and tryptophan (TRP) supplementation). The finishing period (55 to 105 kg) was divided into three phases (55 to 72 kg, 72 to 90 kg and 90 to 105 kg). Pigs fed either the control or Con+L diet grew faster (p<0.05) than pigs fed the Con-LMT or Con+LMTT diet. There was no difference in ADFI among dietary treatments. Phosphorus (P) digestibility was lowest in the control group and highest in the Con+LMTT group (p<0.05). Within each phase, no significant differences in dry matter (DM) and CP digestibilities were found. Although some amino acid digestibilities were affected by dietary treatments, digestibilities of essential amino acids (EAA), non-essential amino acids (NEAA) and total amino acid were not significantly influenced by dietary treatments. For the entire experiment periods, Con+L, Con+LMT and Con+LMTT treatments resulted in 13.4, 18.8 and 21.6% lower total N excretion compared with the control. Con+LMT and Con+LMTT treatments showed significantly lower BUN concentration compared with the control and Con+L treatment (p<0.05), but there was no significant difference in BUN concentration between pigs fed the control and Con+L treatment or between pigs fed Con+LMT and Con+LMTT treatments (p>0.05). Carcass length, backfat thickness and carcass grade were not significantly affected by dietary treatments (p>0.05). In conclusion, reducing dietary CP level by 1 percentage unit and supplementing only LYS at each phase could be a very beneficial feeding strategy for finishing pigs fed under a three phase feeding regimen in terms of both environmental and economical aspects.

• Korean Journal of Ecology and Environment
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• v.51 no.2
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• pp.184-191
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• 2018

During the breeding season, some Eurasian Oystercatchers (Haematopus ostralegus osculans) in Yubu Island foraged in the open mudflat area nearby the breeding ground, instead of the tide water line area, main feeding site throughout the year. We found significant differences in foraging behavior and prey species diversity between the two different feeding site types. Even though the birds took more steps for most probably searching preys, their feeding success was much lower in the open mudflat area than the tide water line area. The multiple peck and boring methods were more frequently adopted to catch polychaetes on the open mudflat area, whereas the single peck method was dominant and gastropods and bivalves were main preys in the tide water line area. This study suggests that the bird shows flexible foraging strategy of shifting feeding site, foraging behavior and preys for better reproductive success.