• Journal of Aquaculture
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• v.9 no.2
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• pp.169-178
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• 1996

This experiment was conducted to develop an experimental model and a semipurified diet for vitamin C requirement study in juvenile Korean rockfish, Sebastes schlegeli. Prior to the start of the feeding trial, fish were fed the control diet for four weeks to deplete their body reserves of vitamin C, Then fish were divided into six groups and given one of the laboratory developed semipurified diets supplementing either 0 (control), 25, 50, 75, 150, o. 1500 mg L-ascorhic acid (AA)/kg diet for eight weeks. Fish fed control diet had lower hematocrit than did fish from groups fed the other diets (P<0.05). Also these fish had significantly lower percent weight gain (WG), feed conversion ratio (FCR) and muscle AA than did fish fed diets containing 150 and 1500 mg AA/kg diet (P<0.05). Diet analysis of vitamin C showed that the control diet had 39,7 mg AA/kg diet. Therefore, these fingings suggest that the experimental model and the semipurified diet can be useful for vitamin C requirement study, and the dietary vitamin C requirement is greater than 40 mg AA/kg diet, but 150 mg AA/kg diet is adequate for the maximum growth in juvenile Korean rockfish.

• The Korean Journal of Food And Nutrition
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• v.25 no.3
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• pp.590-598
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• 2012

Sprague-Dawley rats were fed with normal (Control), high cholesterol (HC), and high cholesterol containing 3.5% pectin-hydrolytic activity industrial enzyme (Viscozyme L)-treated tomato cakes (ETC) for 4 weeks. In the first week, the weight gain of the HC-fed group was significantly increased to 151.7% (p<0.05), compared to the 115.4% weight gain of the ETC-fed group. The feed efficiencies of the Control- and ETC-fed groups ($0.236{\pm}0.041$ and $0.447{\pm}0.030$, respectively) were significantly different to those of HC-fed group ($0.355{\pm}0.034$) (p<0.05). The kidney and epididymal fat pad of the rats fed with ETC were decreased to 0.303 g and 0.274 g, respectively. There were no significant differences in serum cholesterol, triglycerides, high density lipoprotein-cholesterol or low density lipoprotein-cholesterol levels between the HC- and ETC-fed groups. The ETC-fed group exhibited approximately a 1.1-fold higher total antioxidant activity determined by 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) radicals than the HC-fed group at 2 weeks. Glutathione peroxidase activity of the ETC-fed group exhibited 2.5-and 1.3-fold increases at 2 and 4 weeks, respectively.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.29 no.5
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• pp.643-650
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• 1996

A long term feeding trial was conducted to study the effects of different dietary vitamin C levels on growth and its tissue distributions in juvenile Korean rockfish, Sebastes schlegeli. Prior to the start of feeding trial, fish were fed the basal diet supplementing no L-ascorbic acid for four weeks to minimize their body reserves of vitamin C. Then fish were divided into six groups with triplicates and given one of the laboratory semipurified diets supplementing either 0, 25, 50, 75, 150, or 1500 mg L-ascovbic acid (AA)/kg diet $(C_0,\;C_{25},\;C_{50},\;C_{75},\;C_{150},\;&\;C_{1500})$. Fish fed the $C_0$ diet had lower percent weight gain, feed conversion ratio, specific growth rate, and protein efficiency ratio than did fish fed the other diets (P<0.05). After 28 weeks of feeding trial, tissue AA concentrations of fish fed $C_0$ diet were lower than those of fish fed $C_{1500}$ diet (P<0.05). A large amount of total tissue Ah may be reserved in muscle, but the unit AA concentration seemed to be higher in brain than did the other tissues. The growth performances of fish fed $C_{25}$ diet were not different compared to those of fish fed $C_{50}-C_{1500}$ diets (P>0.05), and diet analysis of vitamin C showed that the $C_{25}$ diet had 65 mg AA/kg diet. Therefore, the present long-term study may suggest that the dietary vitamin C requirement is approximately 65 mg AA/kg diet in juvenile Korean rockfish.

• Korean journal of applied entomology
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• v.51 no.4
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• pp.469-477
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• 2012

Ostrinia larvae feed the pods and stem of red bean and seriously damage the bean production from farmers. In this study we investigated biological and developmental characteristics including field collection, host feeding preference, artificial rearing diet, morphological and molecular taxonomical identification, and pheromone analysis for an Ostrinia sp. in Korea. The male adults have massive tibia in the middle legs and 3-lobed uncus in the genitalia. The partial nucleotide sequences of mitochondrial cytochrome oxidase I (COI) and II (COII) were not corresponded to those DNA sequences from other Ostrinia species reported previously in Japan and China. Host plants for this species are also different from the previous species reported. In the gas chromatography (GC) analyses, (Z)-9-tetradecenyl acetate was not detected from the pheromone gland of our species while the component as a sex pheromone was found in O. zaguliaevi and O. zealis, With taken results, we conclude this Ostrinia species in Korea is Ostrinia scapulalis or closely related species. When larvae collected in a fall were incubated in the outdoor condition, they emerged to adult between June and July in the next year. The result indicates that the winter diapause could be started in late larval stage. In addition, we developed a semi-synthetic artificial diet adopted for mass rearing of the O. scapulalis in laboratory.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.8
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• pp.866-871
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• 2006

The nutrient recovery in phosphate crystallization process was investigated by using laboratory scale uptlow reactors, adopting sequencing batch type configuration. The industrial waste lime was used as potential cation source with magnesium salt($MgCl_2$) as control. The research was focused on its successful application in a novel integrated sludge treatment process, which is comprised of a high performance fermenter followed by a crystallization reactor. In the struvite precipitation test using synthetic wastewater first, which has the similar characteristics with the real fermentation effluent, the considerable nutrient removal(about 60%) in both ammonia and phosphate was observed within $0.5{\sim}1$ hr of retention time. The results also revealed that a minor amount(<5%) of ammonia stripping naturally occurred due to the alkaline(pH 9) characteristic in feed substrate. Stripping of $CO_2$ by air did not increase the struvite precipitation rate but it led to increased ammonia removal. In the second experiment using the fermentation effluent, the optimal dosage of magnesium salt for struvite precipitation was 0.86 g Mg $g^{-1}$ P, similar to the mass ratio of the struvite. The optimal dosage of waste lime was 0.3 g $L^{-1}$, resulting in 80% of $NH_4-N$ and 41% of $PO_4-P$ removal, at about 3 hrs of retention time. In the microscopic analysis, amorphous crystals were mainly observed in the settled solids with waste lime but prism-like crystals were observed with magnesium salt. Based on mass balance analysis for an integrated sludge treatment process(fermenter followed by crystallization reactor) for full-scale application(treatment capacity Q=158,880 $m^3\;d^{-1}$), nutrient recycle loading from the crystallization reactor effluent to the main liquid stream would be significantly reduced(0.13 g N and 0.19 g P per $m^3$ of wastewater, respectively). The results of the experiment reveal therefore that the reuse of waste lime, already an industrial waste, in a nutrient recovery system has various advantages such as higher economical benefits and sustainable treatment of the industrial waste.

• Journal of Animal Science and Technology
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• v.44 no.6
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• pp.769-782
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• 2002

Three kinds of green forages(rye, oats and mixed forages) was harvested and mixed with rice straw, wheat bran and 2 grains(corn and soybean), which harvested 2 different dates(common harvesting dates, 7 days early to common harvesting dates). And each mixture was ensiled in 6 poly vinyl chlorides that was 60 liter, immediately. They were opened at 0, 5, 10, 25, 35, 60 and 100 days after ensiling for chemical analysis. And its effects of those TMFFs on feed values were observed. Average contents of water, crude protein, ADF, NDF, Ca and P of formulated TMFs were 72 to 75%, 14.75 to 18.24, 12.47 to 19.07, 39.82 to 47.01, 0.99 to 1.07 and 0.38 to respectively. Crude protein content was the highest in the mixed forages-TMFF and the lowest in the rye-TMFF. The ADF and NDF contents of rye-TMFF were higher than orthers. And CP, ADF, NDF, TDN, P and Ca contents were no significant difference among treatments regardless of storage period and harvest time, but all treatments indicated good quality. Intenal temperatures of TMFF were shown to be 1 to 5$^{\circ}C$ higher than ambient temperatures. The temperature of the Oat-TMFF formulated during winter sustained higher to the level of 6${\sim}$9$^{\circ}C$ for 10 days. The pH of TMFF were 4.0 to 4.2 and the content of $NH_3$-N was shown to be 7.79 to 8.23mg/$d{\ell}$. In the VFA contents, any tendency was not shown at all treatments depending on harvest time. Even though rye-TMFF showed the lowest VFA value. At all treatments except rye-TMFF, propionate production was increased and stable after 25 days of storage. Digestibility of rice straw from TMFF on DM basis was 15${\sim}$20% higher compared with non-treated rice straw.

• Journal of Life Science
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• v.26 no.2
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• pp.190-197
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• 2016

Aflatoxin M₁ can be produced in cow’s milk when cows eat contaminated produce. Milk is a major source of food for infants and for children who have a weak level of immunity, and the detection of Aflatoxin M₁ for risk assessment is necessary in order to reduce the amount of it in milk. In this study, the Aflatoxin M₁ level was monitored for one year in raw milk samples obtained from Chungnam Province, Korea. The milk samples were divided into three categories: 1. milk samples from a standard general farm, 2. milk samples from a HACCP controlled farm, and 3. milk samples from the supply of Aflatoxin M₁ reduced fodder. The average concentrations of Aflatoxin M₁ in milk were 0.023±0.005 ug/l for the standard general farm, 0.017±0.004 ug/l for the HACCP controlled farm, and 0.013±0.003 ug/l for the supply of Aflatoxin M₁ reduction fodder. Milk collected from the supply of Aflatoxin M₁ reduction fodder had the lowest level of Aflatoxin M₁. However, when efficiency and economic aspects are considered the most effective way of reducting Aflatoxin M₁, could be taking milk from the HACCP controlled farm and implementing good feed management. Institutional support from the government, careful management of dairy farming, and a strict farm sanitation program are required in order to lower the level of Aflatoxin M₁ in milk.