• Korean Journal of Poultry Science
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• v.17 no.4
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• pp.318-326
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• 1990

This experiment was conducted to determine the economic housing density levels on caged laying hens The experiment was carried out with 600 ISA Babcock strain of white coder and 450 ISA Brown strain of brown color for production period(21－72 weeks) from May 11. 1987 to June 27. 1988. The levels of housing density was employed 5 or 6 by hen's color from 272 to 920$\textrm{cm}^2$/per hen. The results obtained were summarzed as follows ： 1. Although there were not statistically significant among the housing density levels, The body weight gain for pullet period(14－20 weeks) were in case of white pullet the lowest at the group of high crowding density (272$\textrm{cm}^2$/per pullet) and in case of Brown pullet was the lowest at the group of high crowding density(306$\textrm{cm}^2$/per pullet). 2. Viabillity of pullet from 14 to 20 weeks were more 97% and there urere not statistically significant among the housing density. 3. Viabillity of laying hens was increased as increasing housing density through the etire product period(21－72 weeks) but 453$\textrm{cm}^2$/per hen group(in case of brown hen) showed a significant difference (P＜.05). 4. Rate of egg production through the etire production period(21－72 weeks) were significantly increased by increasing housing density (P＜.05 or .01). 5. Average egg weight through the entire production period(21－72 weeks) was not significantly different among housing density levels at all laying kent 6. In case of white strain, egg mass per hen among treatment during the age of 63－72 weeks were decreased by increasing housing density, meanwhile, in case of brown strain were increased by decreasing housing density during the whole period and there were significant different among the all treatment 7. There were no significant different in feed intake among the all treatment through the entire production period(21－72 weeks) at the white strain laying hens but in case of brown strains, Feed intake were increased by increasing housing density and feeding spece/per hen, and there were significant different among the all treatment 8. Feed requirements per egg at white strain was the highest when the 272$\textrm{cm}^2$/per hen levels and at the brown strains was the highest when the 306$\textrm{cm}^2$/per hen levels, however, among the other treatment were no significant.

• Food Science of Animal Resources
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• v.25 no.2
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• pp.175-188
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• 2005

This study investigated the effects of silkworm droppings (SWD) added diet feeding on quality characteristics of pork loin meat Pigs were divided into 7 treatment groups (10 pigs/group) and subjected to one of seven treatment diets $(0,\;1\%,\;2\%\;and\; 3\%\;SWD\;for\;4 weeks,\;1\%\;2\%\;3\%$ SWD for 8 weeks, SWD diets; total fed diets) before slaughter. Pork loin were collected from the animals (110kg body weight) slaughtered at a commercial slaughterhouse. Pork loin meat were packaged aerobically and then stored at $4^{\circ}C$ for 2, 5, 8, or 12 days. Samples were analyzed for general composition, texture characteristics and physico-chemical properties. pH value was not significantly different between the control and SWD treatment groups. pH of control and SWD treatment groups were increased as the storage period passed General composition, cooking loss and texture was not significantly different between the control and SWD treatment groups. WHC of SWD treatment group was higher than that of control group. WHC of control and SWD treatment groups were significantly decreased as the storage period passed (p<0.05). Meat and fat color (CIE $L^{\ast}$, $a^{\ast}$, $b^{\ast}$) were no significant differences between the control and SWD treatment groups. $L^{\ast}$ and $b^{\ast}$ value of meat color were decreased as the storage period passed There was a not significantly difference in shear force value among control and SWD treatment groups. Shear force value was decreased significantly during storage in all treatment groups. In all results, dietary SWD-supplementation was not affected in general components, texture characteristics and physico-chemical properties. It is suggested that dietary SWD-supplementation could produce of high quality pork.

• Journal of Animal Science and Technology
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• v.48 no.2
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• pp.255-268
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• 2006

Twenty four Hanwoo cull cows were assigned to 2 groups, control and melengerol acetate(MGA)+selenium supplement containing vitamin E(SeE), based on the parity(6.5±1.7 birth) and body weight (493.17±55.61kg), and the experiment was conducted to establish the reasonable fattening method of cull cows for 240 days. Average daily body gains during 240 days were 0.51kg and 0.63kg in control and MGA+SeE, respectively(P<0.10). DDMI/ADG of MGA+SeE group improved compared to control group(P<0.05). Therefore, supplementation of MGA+SeE in concentrates may accelerate both of the growth rate and feed efficiency in Hanwoo cull cows. MQI from MGA+SeE was more developed based on the larger rib-eye area and thinner backfat thickness in carcass than that from control. Marbling score for MGA+SeE tended to increase compared to control. Dietary Se supplementation significantly affected muscle Se concentration in longissimus dorsi meat of MGA+SeE group(P<0.05). Similar results to Se were obtained from α-Tocoperol concentration. During 7 days of simulated retail display, accumulations of thiobarbituric acid reactive substances(TBARS) concentration in beef was greater(P<0.05) in control than in supplemented cows. These results supported the hypothesis that supplementation of MGA+SeE improve the growth performance and carcass grade both by the growth stimulating effect of MGA+SeE and by preventing the oxidation of the longissimus dorsi muscle in Hanwoo cull cows.

• Journal of Animal Science and Technology
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• v.55 no.3
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• pp.219-227
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• 2013

This study was conducted to elucidate the characteristics of equine meat traits and to evaluate the utilization of dried-citrus pulp abundantly produced in Jeju Island as feed ingredient in the diet of finished meat horses. Treatment groups consisted of wheat bran (A) and the dried-pellet mixture of citrus pulp (20%) and wheat bran (80%) (B). Feeding of agricultural by-products were 2 times in a day at the level of 1.5% of body weights. Water and dried-grass forage was not restricted. The average daily gain was similar in both groups. Feed conversion of treatment B showed lower level than that of A. Carcass rate of B was relatively lower than that of A, but meat yield grade of B was higher than that of A. For meat color traits, $L^*$ of B was lighter than that of A, and $b^*$ of group B was lower than that of group A. From the analysis of physical characteristics of equine meats, shearing force had decreased in the treatment B but the levels of drip loss and water holding cavity had increased in the treatment B compared to A. The level of crude fat is lower in the treatment B than the treatment A. For the mineral contents, the treatment B showed higher levels of Ca, K, Mg, Cu and Mn than that of A. For the fatty acid contents, the treatment B showed increased levels of stearic acid, oleic acid, eicosenoic acid, and arachidonic acid compared to A. Consequently, these results suggested that dried-citrus pulp might be utilized as replacement material for equine forage. Please rewrite the whole abstract and should include all required information. Before resubmission, please check it again from a native colleague in your group.

• Korean Journal of Environment and Ecology
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• v.33 no.5
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• pp.515-524
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• 2019

The purpose of this study is to investigate the effects of artificial disturbance by analyzing and comparing the survey data of the Yeongju dam located in Yeongju-si, Gyeongbuk before and after impoundment. We surveyed four sites between the downstream of sediment control to the downstream of Yeongju Dam four times between April and October 2018. The macroinvertebrate data before the survey were gathered from the literature. The total number of benthic macroinvertebrates we observed was $35,037ind./m^2$, including 77 species, 48 families, 14 orders, 7 classes, and 3 phyla. The result of the community analysis showed that the dominant index increased from 0.44(${\pm}0.11$) before impoundment to 0.62(${\pm}0.16$) after impoundment. The diversity index increased from 2.26(${\pm}0.30$) to 1.75(${\pm}0.45$), the evenness index from 0.75(${\pm}0.10$) to 0.66(${\pm}0.14$), and the richness index from 3.11(${\pm}0.98$) to 2.25(${\pm}0.81$). The most dominant species changed from Hydropsychidae spp. to Chironomidae sp. The result of the Principal Components Analysis (PCA) based on Axis 1 showed that the sites of 2014 and Hydropsychidae spp. had a negative value, while the sites of 2018 and Chironomidae sp. had a positive value. In all study sites, the dominance increased while the diversity decreased. The community change was the largest in St. 2. The results of the functional group analysis showed that the scrapers increased while gathering-collectors increased among the functional feeding group and that the clingers decreased while borrows increased among the habitat oriented group. The Benthic Macroinvertebrate Streambed Index (BMSI) decreased from an average of 57.1(${\pm}8.0$, C class) to an average of 30.0(${\pm}12.1$, C class). St. 3 and St. 4, in particular, showed a high reduction rate.

• Korean Chemical Engineering Research
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• v.57 no.6
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• pp.874-882
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• 2019

In this study, the gasification characteristics of four types of unused woody biomass and one waste wood in a lab-scale bubbling fluidized bed gasifier (Diameter: 0.11 m, Height: 0.42 m) were investigated. Effect of equivalence ratio (ER) of 0.15-0.3 and gas velocity of $2.5-5U_0/U_{mf}$ are determined at the constant temperature of $800^{\circ}C$ and fuel feeding rate of 1 kg/h. The silica sand particle having an average particle size of $287{\mu}m$ and olivine with an average particle size of $500{\mu}m$ were used as the bed material, respectively. The average product gas composition of samples is as follows; $H_2$ 3-4 vol.%, CO 15-16 vol.%, $CH_4$ 4 vol.% and $CO_2$ 18-19 vol.% with a lower heating value (LHV) of $1193-1301kcal/Nm^3$ and higher heating value (HHV) of $1262-1377kcal/Nm^3$. In addition, it was found that olivine reduced most of C2 components and increased $H_2$ content compared to silica sand, resulting in cracking reaction of tar. The non-condensable tar decreases by 72% ($1.24{\rightarrow}0.35g/Nm^3$) and the condensable tar decreases by 27% ($4.4{\rightarrow}3.2g/Nm^3$).

• Korean Journal of Environment and Ecology
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• v.36 no.2
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• pp.150-164
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• 2022

The objective of this study is to analyze the biodiversity changes and characteristics of the benthic macroinvertebrate community in the Nakdong River with eight weirs, which was constructed as one of the Four Major River Restoration Projects from May to October 2020. The study also includes the analysis of changes in the major groups of benthic macroinvertebrates for about ten years, from 2010 to 2020. The surveys collected 97 species of benthic macroinvertebrates belonging to 83 genera, 52 families, 18 orders, five classes, three phyla, and 128.1 individuals/m². Chironomidae sp. and Tubificidae spp., which are pollutant indicators, dominated throughout the sections. The community analysis result shows the average dominant index and the diversity index of 0.62±0.20 and 1.87±0.63, respectively, and indicated the most stability of the freshwater ecosystem in the upper stream of the Nakdong River. The survey showed dominance by Chironomidae sp. at the center of the Nakdong River weir and the most unstable community in Chilgok and Gangjeong Goryeong weirs. The results of the community stability analysis showed a high distribution of the characteristic group I with high resilience and resistance and small distribution of characteristic group III with low resistance and resilience, indicating a very unstable condition of communities in the Nakdong River weir section. Predators were relatively abundant among the functional feeding groups (FFGs), whereas shredders, gathering-collectors, and filtering-collectors were relatively lower. Among the habitat orientation groups (HOGs), burrowers and climbers were dominant, indicating a wide distribution of groups in ecosystems with low dissolved oxygen. An endangered species level II of Macromia daimoji was found in Sangju and Nakdan weirs. The analysis results for 10 years from 2010 showed that the number of species and populations increased immediately after the dam construction but plummeted in 2016 and are now stabilizing. Chironomidae spp. has been dominant in all sections over the past 10 years, and they are currently maintained at a rate of about 50%. The EPT groups have decreased significantly since 2011, and the Plecoptera and Trichoptera of the group have not yet been restored. The population of Tubificidae spp. showed an increase after construction was completed in 2012 and drastically increased in 2015 and 2020. The species of Cristaria plicata, designated as endangered species level I, has not been observed since 2011 in Hapcheon Changnyeong weir. Moreover, Macromia daimoji was rarely observed in seven weirs until 2015, and it has been confirmed that the current distribution habitat has decreased rapidly.

• Korean Journal of Environmental Biology
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• v.40 no.4
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• pp.363-373
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• 2022

On April 29, 2021 (1st), June 2 (2nd), and August 17 (3rd), we surveyed benthic macroinvertebrates fauna at Muljangori-oreum wetland in Bonggae-dong, Jeju Island, Korea. Muljangori-oreum wetland was divided into four areas. The survey was conducted in three accessible areas (areas 1-3). As a result of habitat environment analysis, the average monthly temperature from 2017 to 2021 was the highest in July and August and the lowest in December and February. This pattern was repeated. As a result of analyzing changes in vegetation and water surface area through satellite images, normalized difference vegetation index (NDVI) increased from February to July and decreased after July. Normalized difference water index (NDWI) was analyzed to show an inverse relationship. A total of 21 species from 13 families were identified in the qualitative survey and a total of 412 individuals of 24 species from 15 families were identified in the quantitative survey. A total of 26 species from 17 families, 8 orders, 3 classes, and 2 phyla of benthic macroinvertebrates were identified. The dominant species was Chronomidae spp. with 132 individuals (32.04%). Noterus japonicus was a subdominant species with 71 individuals (17.23%). As a result of comparative analysis of species identified in this study and the literature, it was confirmed that species diversity was high for Coleoptera and Odonata. Main functional feeding groups (FFGs) were found to be predators. Habitat orientation groups (HOGs) were found to be swimmers. In OHC (Odonata, Hemiptera, and Coleoptera) group, 17 species (73.91%) in 2021, 23 species (79.31%) in 2016, 26 species (86.67%) in 2018, and 19 species (79.17%) in 2019 were identified. Cybister japonicus, an endangered species II, was confirmed to inhabit Muljangori-oreum wetland in the literature. Ten individuals (2.43%) were also confirmed to inhabit Muljangori-oreum wetland in 2021. Therefore, continuous management and habitat protection are required to maintain the habitat environment of C. japonicus in Muljangori-oreum wetland.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.1
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• pp.21-26
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• 2001

To examine functionality of depolymerized alginate obtained by hydrolysis of alginate through a heating process at $121^{\circ}C$ on gastrointestinal physiology, the changes of body weight, organ weight and length, pancreatic and small intestinal composition, and light microscopy (LM) observation of small intestinal microvilli's appearances were checked in the rats. Rats were fed diets containing $1\%, 5\%, and 10\%$ of each depolymerized alginate (HAG-10, HAG-50, HAG-100) and alginate for 35 days, The feeding of 5 and $10\%$ HAG-50 and $10\%$ alginate diets for 35 days significantly depressed the body weight gain, but increased the length and weight of the small intestine and cecum in rats (p<0.01). Pancreatic protease activity was decreased significantly (p<0.01) in all groups except lo/o of HAG-10 diets, but the protein content increased in all groups, However, pancreatic amylase and lipase activities as well as DNA and RNA content were not significantly different. The small intestinal protein and the DNA content were the highest in diets fed $5\%$ HAG-50; RNA content increased significantly (p<0.01) in all groups except in the fiber-free diets. Light microscopy (LM) observation showed growth of small intestinal microvilli with numerous ridges; the multiplication of the convolution goblet cells in rats fed with diets containing $5\%$ of HAG-50 were more than others group.

• Proceedings of the Korean Aquaculture Society Conference
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• 2003.10a
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• pp.68-69
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• 2003

The present study was conducted to investigate the effects of dietary supplementation of $\beta$-1,3 glucan and feed stimulants(BAISM) as a feed additive for juvenile olive flounder (Paralichthys olivaceus). Eight experimental diets supplemented with $\beta$-1,3 glucan and feed stimulants at 0%, $\beta$-1,3 glucan 0.05% ＋ Baism 0.45%, $\beta$-1,3 glucan 0.05% ＋ Baism 0.95%, $\beta$-1,3 glucan 0.10% ＋ Baism 0.90%, $\beta$-1,3 glucan 0.10% ＋ Baism 1.90%, $\beta$-1,3 glucan 0.15% ＋ Baism 1.35%, $\beta$-1,3 glucan 0.15% ＋ Baism 2.85% and $\beta$-1,3 glucan 0.30% ＋ Baism 2.70% of diets as a dry-matter(DM) basis were prepared. Three replicate groups of fish averaging 9.2 $\pm$ 0.1g (Mean $\pm$ SD) were randomly distributed in each aquarium as a group of 15 fish and fed one of eight experimental diets for seven weeks. After the feeding trial, $\beta$-1,3 glucan 0.10% ＋ Baism 0.90%, $\beta$-1,3 glucan 0.10% ＋ Baism 1.90% diets had a higher weight gain (WG), feed efficiency(FE), specific growth rate(SGR) and protein efficiency ratio(PER) than did fish fed 0%, $\beta$-1,3 glucan 0.05% ＋ Baism 0.45%, $\beta$-1,3 glucan 0.05% ＋ Baism 0.95%, $\beta$-1,3 glucan 0.15% ＋ Baism 2.85% and $\beta$-1,3 glucan 0.30% ＋ Baism 2.70% (P<0.05). however, there was no significant difference among fish fed $\beta$-1,3 glucan 0.05% ＋ Baism 0.45%, $\beta$-1,3 glucan 0.05% ＋ Baism 0.95%, $\beta$-1,3 glucan 0.15% ＋ Baism 2.85% and $\beta$-1,3 glucan 0.30% ＋ Baism 2.70%(P>0.05). and $\beta$-1,3 glucan 0.10% ＋ Baism 0.90% diets had a higher peak value of CL(Chemiluminescence) and lysozyme activity, than did fish fed the other diets (P<0.05). These results indicated that dietary sipplementation of $\beta$-1, 3 glucan and Baism affected growth, feed efficiency, specific growth rate, protein efficiency ratio, Peak value of CL and Lysozyme activity, and the optimum dietary supplementation level of $\beta$-1, 3 glucan and Baism as a feed additive could be approximately $\beta$-1, 3 glucan 0.10% ＋ Baism 0.90% of diet in juvenile olive flounder (Paralichthys olivaceus).