• 한국물환경학회지
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• 제20권1호
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• pp.48-54
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• 2004

Two methods, a Ceriodaphnia algal uptake suppression test (CAUST) and a new toxicity test based on temperature control (TTBTC) which are based on feeding behaviour and temperature control, respectively, were developed and compared for the adoption as the better methodology for short-term toxicity screening. As previously published by Lee et aI., (1997), the CAUST method is based on the feeding behaviour of C. dubia and requires as little as 1 hour of contact time between C. dubia neonates and toxicant. However, even though CAUST requires only 1 hour of contact time, this method still take many hours for the preparation and measurement. Before the test starts, neonate digestive tracts were cleared by feeding yeast to the daphnids, Neonates were then exposed to toxicant, followed by addition of Scenedesmus subspiatus into the bioassay vessels. Daphnids were examined under the bright-field microscope with the presence of algae (indicated by a green colored digestive tract) or the absence of algae. Uptake indicated no toxic effect, whereas, absence of uptake indicated toxic inhibition. Unlike CAUST, the newly developed method (TTBTC) is based on just temperature control for the toxicity test of C. dubia. Initially, neonates are exposed to toxicants while the temperature of water bath containing media increased to $35.5^{\circ}C$. After 1.25 hour of contact time, the number of the daphnids, either live (no toxic effect) or dead (toxic effect), is counted without the aid of any instrument. In both methods, median effective concentrations ($EC_{50}$ values) were computed based on the results over a range of dosed toxicant concentrations. It showed that TTBTC was as sensitive as the standard 48-hour acute bioassay and CAUST. TTBTC and CAUST were much more sensitive than the I-hour I.Q. test and 30-minute Microtox. This study indicates that TTBTC is an easier and more rapid toxicity test than the standard 48-hour acute bioassay and even CAUST.

• 한국축산식품학회지
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• 제42권3호
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• pp.517-535
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• 2022

The primary aim of this study was to evaluate the effect of feeding alfalfa: Concentrate at different ratios (8:2 or 2:8) to Korean native black goats (KNBG) for 90 days on meat quality and bioactive compound content. Feeding KNBG alfalfa and concentrate at different ratios did not impact meat pH, color, microorganism composition, volatile basic nitrogen levels, or lipid oxidation. The low alfalfa (KLA) group exhibited increased oleic acid and monosaturated fatty acid levels, both of which impact the palatability traits of meat. The abundance of bioactive compounds increased in the loin meat of the KLA group, leading to an increase in antioxidant activities. Our results suggest that feeding alfalfa and concentrate at a 2:8 ratio to KNBG can increase taste-related fatty acids and bioactive compounds in loin meat, relative to that achieved by feeding at an 8:2 ratio. Further investigation is required to evaluate the quality and the metabolites of bioactive compounds in KNBG meat and the effect of the different dietary ratios of forage and concentrate.

• Journal of Animal Science and Technology
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• 제46권5호
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• pp.773-782
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• 2004

본 연구는 산차와 비유기가 다양한 Holstein 종 56두를 사용하여 사료섭취량과 에너지요구 량을 근거로 개체별 사료에너지요구량의 서열을 설정하고, 이를 3개 우군으로 나누어 각 우군의 상반평균치에 기준하여 자가배합사료(herdmix ration)를 조제한 후 이것을 이용한 사양체계가 비유기 및 산차에 미치는 영향을 관행 사양체계와 switch-over method로 비교하였다. 자가배합사료 급여체계는 전 비유기 동안 산유량과 유지율을 증진시켰으며(P<0.05), 산차별 생산능력도 모든 산차에서 향상되었다(P<0.05). 비유단계별 성적에서는 비유초기와 중기에서 Herd-mix구의 설제산유량(AMY) 및 지방보정유량(FCM)이 유의적으로 증가하였으나(P<0.05) 유지율은 유의차가 없었다. 비유말기에는 AMY, 유지율 및 FCM 모두 Herd-mix구가 관행구에 비하여 증가하였으며 특히 유지율과 FCM이 현저하게 증가하였다(P<0.01). Herd-mix구와 관행구의 FCM 비유지속성은 각각 93.24%와 92.69%로서 Herd-mix구의 비유지속성이 높았으며 비유곡선의 형태도 이상적 추세를 보였다. 유대와 사료비를 고려한 조수익을 산출한 결과 Herd-mix구가 관행구보다 40% 높았다. 결론적으로, 본 연구는 젖소의 에너지요구량과 사료 에너지 농도를 정확히 평가하여 우군을 편성한 후 그 상반평균을 배합목표로 설정하고 사용할원료에 대한 실질적인 평가를 근거로 배합비를 설정하는 것이 산유능력을 향상시킴과 동시에 경제적으로 유려하다는 사실을 입증하였다.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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• pp.171-172
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• 2006

The effect of the preparation factors, such as the feeding mode and rate of raw materials, the reaction temperature and the surfactant on the size distribution of molybdenum trioxide particle were investigated by orthogonal test. The optimum conditions for the preparation of $MoO_3$ precursors are as following; opposite feeding fast, reaction temperature of $60^{\circ}C$ and adding dispersant.

• Journal of Animal Science and Technology
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• 제52권3호
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• pp.205-212
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• 2010

Two experiments were conducted to study the effects of dietary protein level and phase feeding regimens on performance, carcass characteristics and pork quality in growing-finishing pigs. In both experiments, growing pigs (n=90; barrows; Landrace $\times$ Yorkshire $\times$ Duroc) were allotted to 3 treatments. Each treatment had 3 replicate pens comprising 10 pigs in each. In Exp. 1, pigs (average body weight $25.06{\pm}0.57\;kg$) were fed diets having low (17.50-14.50-12.51%), medium (19.49-17.50-13.87%) or high (22.47-19.49-16.36%) CP concentration (LP, MP and HP diets, respectively) diets during grower-finisher I-finisher II phases, respectively. Feeding of MP diet resulted in higher (P<0.05) ADG and better FCR than pigs fed LP diet. Pigs fed HP diet had lower (P<0.05) pork color and marbling score. Meat of pigs fed LP diet had higher (P<0.05) Thiobarbituric acid reactive substances (TBARS), while meat of pigs fed HP and LP diets had greater drip loss than pigs fed MP diet. In addition, meat from pigs fed LP diet was darker while meat of pigs fed HP and MP diets was paler and redder. In Exp. 2, pigs (average body weight $10.40{\pm}0.61\;kg$) were subjected during 126 days to three or four phase regimes of different duration. The treatments T1 and T2 were subjected to four phase feeding regimens (grower I, grower II, finisher I and finisher II) for 22, 42, 32 and 30 days (T1) and 40, 40, 25 and 21 days (T2), respectively, while T3 was subjected to three phase feeding regimen (grower I, grower II and finisherI) for 40, 56 and 30 days, respectively. Duration of phase feeding regimens had no effect (P>0.05) on the performance, carcass traits and meat quality of pigs. These results suggest that both high and low levels of CP have a negative effect on performance and pork quality; however, alterations in the phase feeding regimens do not have any discernible effect on the performance and pork quality in growing-finishing pigs.

• Asian-Australasian Journal of Animal Sciences
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• 제18권2호
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• pp.241-248
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• 2005

This study is aimed at understanding the role of arsenic in Roxarsone in causing fatty livers in mule ducks. One hundred 10-week-old mule ducks were randomly divided into 5 groups. Ducks received 2 weeks of various treatments followed by 2 weeks of withdrawal. The treatments were non-treatment (control), 300 mg/kg Roxarsone inclusion for 2 weeks ($1^{st}$ and $2^{nd}$ week), Roxarsone inclusion for one week ($2^{nd}$ week only), restrict feeding, or Roxarsone analogue (3-nitro-4-hydroxyphenyl acid) inclusion. Results showed that feed intake and body weight in the Roxarsone groups and the restrict feeding group decreased significantly during the treatment period. However only the liver and heart weights were significantly decreased (p<0.05) in the restrict feeding group. Fatty acid synthetase (FAS) activity showed a significant decrease (p<0.05) in the Roxarsone groups and the restrict feeding group, two-week-Roxarsone treatment significantly increased NADP-malic dehydrogenase (MDH) activity compared to the restrict (p<0.05). After 2 weeks drug withdrawal, the 1-week-Roxarsone or restrict feeding group showed significantly increased (p<0.05) glucose-6-phosphate dehydrogenase (G-6-PDH) activity (p<0.05). Two-week-Roxarsone treatment significantly decreased (p<0.05) the high density lipoprotein (HDL) and increased (p<0.05) the low density lipoprotein (LDL) and very low density lipoprotein (VLDL) ratio. After drug withdrawal, the 1-week-Roxarsone or restrict feeding group showed significantly increased (p<0.05) creatine kinase (CK) activity. The 2-week-Roxarsone treatment group showed significantly increased (p<0.05) aspartate aminotransferase (AST) activity. The restrict feeding treatment group showed significantly decreased (p<0.05) total protein (TP) concentration. After drug withdrawal, the related enzyme activities in the blood that reflected the liver function were restored to the normal physiological range, except for the total bilirubin concentration and CK activity in the 1-week-Roxarsone group. This group showed a significant increase (p<0.05). Thus, the reasons for liver enlargement in the Roxarsone and restrict feeding groups were different.

• 한국가금학회지
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• 제23권4호
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• pp.185-191
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• 1996

A feeding trial was conducted to investigate the effect of skip-a-day feeding program in early growing stage of male broiler chicks on the compensatory growth, and development of visceral organs during the later realimentation period. Day-old 328 male broiler chickens( Avian x Avian) were divided into control(ad libitum feeding) and skip-a-day feeding(limited feeding) treatments. Each treatment was consisted of 4 pens( replicates) of 41 birds each. Chickens on the skip-a-day program were fasted every other day during the second wk of age(8~15 d of age). During the starter period(0~4 wk), chickens were fed a commercial crumble diet. A commercial pellet diet was fed to chickens during the finishing period( 5~8 wk). Chickens were group-weighed every week, and one bird was selected from each pen to measure carcass characteristics. The skip-a-day program delayed the growth rate of male broilers up to 4 wk of age(P

• 한국연소학회지
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• 제10권2호
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• pp.26-34
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• 2005

The performance of oxygen combustion with $CO_2$ feeding was investigated in a pyrex tube furnace. The inverse type multi-hole burner was used for improving mixing and wide operating range. It introduced oxygen, fuel, and oxygen, respectively, from center tube to outer tubes. Oxygen combustion characteristics with excess oxygen ratio, oxygen feeding ratio, and $CO_2$ feeding flow rate were studied to optimize the operating condition and to apply the oxygen combustion with recirculation of flue gas to a real furnace. This paper presents results on the effect of $CO_2$ feeding flow rate on the structure of the flames and concentrations of NO and CO emissions. The visible flame length was shortest due to well mixing between fuel and oxygen when the oxygen feeding ratio was 0.25. The NO emission was reduced drastically regardless of excess oxygen ratio when the $CO_2$ feeding flow rate was larger than 15 lpm. The CO emission is varied by changing the $CO_2$ feeding flow rate but the CO emission characteristics is highly affected by excess oxygen ratio. When the excess oxygen ratio is below $\lambda=1.1$, the CO emission increased as the $CO_2$ feeding flow rate increased.

• 한국식생활문화학회지
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• 제28권2호
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• pp.125-134
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• 2013

This study investigated the effect of a health-related lifestyle on knowledge, attitude, control belief and behavior intention toward breast-feeding of male and female university students in order to develop a breast-feeding education program for students of childbearing age. The subjects were 445 university students (125 male and 325 female) residing in eight provinces in Korea. The overall percentage of subjects intending to breast-feed their baby was 80.7% (73.6% of males and 84.2% of females). Overall, 84.2% of the subjects had high concerns about their health status. Scores reflecting a positive attitude, knowledge, and control beliefs toward breast-feeding were significantly higher (p<0.05~p<0.001) in female students, students majoring in medicine, and higher grades. The students who scored high at attitude, knowledge, and control beliefs also had a significantly higher (p<0.001) intention to breast-feed. When we investigated the sub factors of attitudes toward breast-feeding, significantly more students taking nutrient supplements scored high for physiological factors (p<0.05) and health-related factors (p<0.01). Significantly more non-smoking and non-drinking students scored high for health-related factors (p<0.001) and physiological factors (p<0.001), respectively. The intention to breast-feed was found to be significantly higher (p<0.01) in students who did not smoke, but not with other health-related lifestyles. In summary, these results indicate that the majority of university students intend to breast-feed, with students having a positive attitude, higher knowledge, and stronger control beliefs having a higher intention to breast-feed. Although a student's health-related lifestyle affects their attitudes on the physiological and health-related aspects of breast-feeding, only smoking status had an observable connection on the intention to breast-feed. Thus, when developing breast-feeding education programs for students, we recommend efforts to enhance a favorable attitude, knowledge, and control beliefs toward breast-feeding.

• Asian-Australasian Journal of Animal Sciences
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• 제20권3호
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• pp.365-372
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• 2007

This study was conducted to determine effects of salinomycin (SL) on feeding-induced changes in glucose kinetics and blood VFA concentrations in sheep fed a high-roughage diet. Four sheep were fed the diet with or without 20 mg/kg diet of SL once daily for 21 d. Glucose entry and utilization rates were determined during the prefeeding and 3 h postfeeding periods, using a [$^{13}C_6$]glucose dilution method and non-steady state equations. Ruminal characteristics and concentrations of blood VFA, plasma glucose and insulin were also measured during the same periods. A feeding-induced increase in ruminal total VFA concentration tended to be inhibited (p<0.10) with SL, although ruminal pH was unaffected (p>0.10) with SL or by feeding. Salinomycin decreased (p<0.05) acetate proportion and increased (p<0.05) propionate proportion in the rumen, but did not modify these changes in response to feeding (p>0.10). A feeding-induced increase in blood acetate concentration was attenuated (p<0.05) with SL. Salinomycin tended to increase (p<0.10) blood propionate concentration without modifying its response patterns to feeding (p>0.10). Plasma concentrations of glucose or insulin were unaffected (p>0.10) with SL. Salinomycin tended to enhance (p<0.10) glucose entry and utilization rates. Feeding also enhanced (p<0.01) both rates, whereas their interactive effect was not detected (p>0.10). We conclude that SL possibly enhances whole body glucose entry and utilization with an increase in blood propionate concentration in sheep given a high-roughage diet, although SL does not appear to affect their responses to feeding.