• Journal of Animal Science and Technology
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• 제47권2호
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• pp.195-204
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• 2005

The current study was conducted to investigate the effects of dietary conjugated linoleic acid(CLA) on growth performance and body fat metabolism in broiler chickens. A total of 48 male birds aged 3 days were randomly allotted into three dietary groups; CORN(com oil 1.5%), CLA I (com oil 0.75 %+ CLA 0.75 %) and CLA II(CLA 1.5%) groups. After feeding commercial diet ad libitum for 3 weeks, eight selected birds on the basis of body weight were housed, two birds in a cage, and continuously given ad libitum corresponding experimental diet for another 2 weeks. As a result, dietary addition of CLA did not influence on body weight, gain and feed conversion rote. The relative weights of the liver and deposited fats(abdominal and thigh fat' pads) were not also affected by the dietary treatments. Serum glucose, triglyceride and cholesterol levels markedly( P < 0.05) decreased in CLA II compared with those in CORN group. However, serum nonesterified fatty acid(NEFA) was not altered by dietary CLA. Serum leptin level was tended to be decreased by dietary CLA without statistical difference. The diet supplemented with CLA caused a significant(P< 0.05) decrease in hepatic total lipid and NEFA without changing triglyceride level. Also, feeding dietary CLA at the level of 1.5% reduced leptin mRNA expression in the liver and abdominal fats compared with feeding com oil, In conclusion, our results suggest that dietary 1.5% CLA may affect, at least in part, lipid metabolism in the liver of broiler chickens.

• Journal of Animal Science and Technology
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• 제55권2호
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• pp.131-139
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• 2013

The aim of this study was to assess the effects of housing systems on physiological and immunological responses as stress indicators in laying hens. A total of 500 White Leghorn aged 16 weeks were allotted into ten conventional cages (10 birds/cage and 810 $cm^2$/bird) and four floor pens (100 birds/pen and 2,800 $cm^2$/bird) for 24 weeks. The hens housed in conventional cages with higher stocking density resulted in a significantly (P<0.05) lower BW compared with those housed in floor pens with lower stocking density without affecting the relative weights of immune organs between housing conditions. In plasma biochemical values, cholesterol and corticosterone were significantly (P<0.05) lower in the hens housed in floor pens compared with those housed in conventional cages. In pro-inflammatory cytokines, hepatic interleukin (IL)-10 and interferon-gamma (IFN-${\gamma}$) levels were significantly (P<0.05) higher in the hens housed in conventional cages compared with those kept in floor pens. Splenic and thymic IFN-${\gamma}$ expression was significantly (P<0.05) up-regulated in the hens kept in conventional cages compared with those kept in floor pens without affecting IL-1, IL-10, lipopolysaccharide- induced tumor necrosis factor-${\alpha}$ factor (LITAF) and inducible nitric oxide synthase (iNOS). In the bursa of Fabricius, IL-10 and iNOS expression of the hens housed in conventional cages were significantly (P<0.05) higher compared with those of the hens housed in floor pens. In conclusion, layers housed in conventional cages enhanced plasma cholesterol, corticosterone and some pro-inflammatory cytokines in the immune organs compared with those in floor pens.

• 한국가금학회지
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• 제44권3호
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• pp.161-172
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• 2017

This study was conducted to determine the effect of Saccharomyces cerevisiae (SC) as a dietary probiotic and evaluated the most suitable feeding interval for this probiotic on growth performance, carcass yield, and meat quality parameters in broiler chickens. In total, 1,050 one-day-old Cobb 500 chicks were randomly assigned to one of seven dietary treatment groups, in a $2{\times}3$ factorial arrangement with 3 SC dosages (0.6%, 1%, and 1.4%) and two feeding intervals [long term (LT) for 35 days and short term (ST) for 28 days after hatching], with a negative control diet (NC; 0% SC). Triplicate experiments were performed with 50 birds per cage. Broilers fed a diet including SC showed increased (p<0.01) daily gain and feed efficiency compared to the control. Further, broilers fed the 1.4% SC supplemented diet showed a significantly increased (p<0.01) average daily gain (ADG) and feed conversion ratio (FCR) compared to broilers fed the 0.6% and 1% SC incorporated diets. Similarly, broilers fed an LT SC diet showed a greater (p<0.01) increase in ADG and FCR compared to broilers fed an ST SC diet. Moreover, broilers fed an LT SC diet displayed a reduced (p<0.05) meat pH, gizzard weight, and increased (p<0.05) meat water-holding capacity compared to broilers fed an ST SC diet. Broilers fed the 1.4% SC supplemented diet showed increased (p<0.05) thigh muscle weight compared to broilers fed the 0.6% and 1% SC supplemented diets. In conclusion, broilers fed LT SC diets showed improved growth performance and carcass quality parameters compared to broilers fed ST SC diets, and the NC diet, from hatching to day 35.

• 한국가금학회지
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• 제44권2호
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• pp.67-73
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• 2017

The purpose of our study was to determine the effects of varying levels of energy, protein, and amino acids on the performances of laying hens. A total of 240 Hy-Line Brown laying hens at 36 weeks of age were used in this 4-week feeding trial. The hens were randomly allocated to five treatment diets, with eight replications of six hens in each replicate cage. The treatment diets were as follows: A- basal diet + 18% crude protein, metabolizable energy 2,800 kcal, total (methionine + cysteine) 0.65%; B- basal diet + 17% crude protein, metabolizable energy 2,700 kcal, total (methionine + cysteine) 0.59%; C- basal diet + 16.5% crude protein, metabolizable energy 2,700 kcal, total (methionine + cysteine) 0.59%; D- basal diet + 16.5% crude protein, metabolizable energy 2,700 kcal, total (methionine + cysteine) 0.54%; and E- basal diet + 16% crude protein, metabolizable energy 2,680 kcal, total (methionine + cysteine) 0.54%. The study results revealed that the hen-day egg production of hens that were fed with low-energy diets (B, C, and D) was comparable with that of hens fed with high-energy diet A, whereas average daily feed intake in hens fed treatment diet D and E was significantly higher (P<0.05) than that in hens fed treatment diet A. Overall, the eggshell thickness was unaffected by any of the treatment diets. Egg weight was comparable among the treatment diets, except for treatment diet E. Haugh unit improved with decreasing levels of dietary energy, protein, and methionine + cysteine in the diet. We can summarize that laying hens fed with low dietary energy and low crude protein treatment diets B, C, and D had satisfactory performance compared with those fed with high-energy treatment diet A. This indicates that there is the potential to reduce feed costs by formulating diets with lower energy and low protein levels.

• Toxicological Research
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• 제20권2호
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• pp.159-166
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• 2004

Safety pharmacological properties of CJ-11555, an anti-cirrhotic agent, were investigated in experimental animals and in vitro test system. CJ-11555 had no effects on normal body temperature in rats, motor coordination, chemoshock induced by pentetrazol, electric shock induced by electric shocker and writhing syndromes in mice at dose levels of 100, 300 and 1,000 mg/kg. CJ-11555 inhibited intestinal activity and prolonged hexobarbital-induced sleeping time in mice at the dose level of 1,000 mg/kg. CJ-11555 affected on general activity and behaviour tests in SD rats, such as lacrimation, ptosis, piloerection, decreased body tone, abnormal dispersion within the cage, diarrhoea, red colored faeces, slight hypothermia and decreased grooming, at the dose level of 1,000 mg/kg in rats. CJ-11555 was effected on cardiovascular and respiratory system in anesthetized beagle dogs, such as tachycardia, increase of mean blood pressure and decrease of PR interval, decrease of respiratory rate and minute volume, at dose levels of 10 and 30 mg/kg. However, these effects were also observed in vehicle treated anesthetized beagle dogs. In in vitro experiments, CJ-11555 inhibited agonists (histamine, acetyl-choline or $BaCl_2$) induced contraction of isolated guinea-pig at the concentration of 30$\times$$10^6$ M. CJ-11555 was weekly inhibited hERG channel current at concentrations of 10 and 30$\times$$10^6$ M, and $IC_{50}$ was estimated to be higher than 30${\times}$$10^6$M. Based on these results, it was concluded that CJ-11555 affected on cardiovascular and respiratory system, general activity and behaviour and hexobarbital-induced sleeping time at the dose level of 1,000 mg/kg and contraction of the smooth muscle and hERG channel current at the concentration of 30$\times$$10^6$ M.

• 한국식물병리학회지
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• 제1권3호
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• pp.190-194
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• 1985

벼검은줄오갈병 매개충인 애멸구의 기주식물 선호성은 실내유균접종과 포장상태에서 공히 옥수수가 벼보다 낮으나 발병율은 아주 높았다. 바이러스가 매개충의 생태에 미치는 영향은 보독충이 무독충보다 성충의 생존일수, 부화약충수 및 성충율에서 심한 장애를 나타냈다. 벼에서는 감염초기부터 후기까지 건물중이 이병주가 건전주보다 낮았다. 그러나 옥수수에서는 감염초기에 이병주가 건전주보다 건물중이 높았다. 한천내확산법 및 미량심강법에 의한 감염바이러스의 정량결과, 항혈청과의 반응정도는 옥수수잎, 벼줄기, 벼잎, 옥수수줄기에서 부분순화한 항원바이러스의 순으로 나타났다. 이병기주식물의 phloem gall 형성에서 저온처리의 효과가 인정되었다.

• 한국유기농업학회지
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• 제20권4호
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• pp.643-654
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• 2012

본 실험은 점착트랩을 이용하여 토마토에 나타나는 가루이류에 대한 방제 효과를 알아보기 위해 수행하였다. 담배가루이와 온실가루이는 두 종 모두 성충 대부분이 백색과 청색보다 황색 트랩에 포획되었다. 토마토 주위에 높이별로 점착트랩을 설치하였을 때 담배가 루이가 포획된 마릿수는 큰 차이를 보이지 않았지만 온실가루이는 상단에 설치한 트랩에 더 많이 포획되었다. 온실가루이는 기주가 어릴 때 트랩에 더 유인되는 경향을 보여주었다. 담배가루이와 온실가루이에 대한 황색점착트랩의 유인력은 천적인 담배가루이좀벌과 온실가루이좀벌에 대한 트랩의 유인력과 차이를 보이지 않았다. 토마토유묘가 있는 스크린케이지 안에 황색점착트랩을 설치한 결과 담배가루이와 온실가루이 밀도가 80% 이상 감소하였다. 방제용 점착트랩을 설치한 토마토재배 온실의 가루이밀도가 무처리온실에 비해 3분의 1 이하로 낮게 나타났다.

• 한국소음진동공학회논문집
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• 제16권2호
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• pp.163-168
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• 2006

The PWR Nuclear Fuel assembly consists of more than 250 fuel rods that are supported by leaf springs in the cells of more than 10 Spacer Grids (SG) along the rod length. Since it is not easy to conduct mechanical tests on a full-scale model basis, the small-scaled rod bundle $(5\times5)$ which is called partial fuel assembly is generally used for various performance tests during the development stage. As one of the small-scaled tests, a flow test should be carried out in order to verify the performance of the spacer grid to obtain the Flow-Induced Vibration (FIV) characteristics of the scaled fuel assembly over the specified flow range. A vibration test should be also performed to obtain the modal parameters of the assembly prior to the flow test. In this study, we want to develop the estimation procedure of the damping ratio for the scaled test assembly. For the damping factor of the partial fuel assembly and the grid cage at the first vibration mode, as one of the vibration tests, a so-called pluck testing has been performed in air as a preliminary test prior to in-flow damping measurement test. Logarithmic decrement method is used for calculation of the damping ratio. Estimated damping ratio of the partial fuel assembly is about $0.7\%$ with reasonable error of $2\%$ for the previous results. Nonlinear behavior of the partial fuel assembly might be stem mainly from the rod-grid support configuration.

• Natural Product Sciences
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• 제8권2호
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• pp.44-47
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• 2002

The effects of Eurycoma longifolia Jack on masculine copulatory behaviour were studied in the middle aged male Sprague-Dawley rats, 9 months old and retired breeders after dosing them with 500 mg/kg twice daily for 10 days prior to test. The test lasted for 30 minutes after a 20 minute adaptation period, was carried out on the 11th day during the dark phase of the light-dark cycle (2000-0700 hours) and in subdued light, using a modified copulation cage but with the presence of a piece of mirror of appropriate size to facilitate observation. Results showed that the mean values of EL-1, EL-2 and EL-3 of the control middle aged male rats were 103.20 sec, 91.21 sec and 80.00 sec but were significantly (p<0.05) increased to 118.40-120.20 sec, 101.24-171.28 sec and 100.42-110.21 sec respectively in the methanol-chloroform, methanol-butanol-water and methanol-butanol treated middle aged male rats. However, further results also showed that PEI-1 and PEI-2 of the control middle aged male rats were 182.30 sec and 257.2 sec but were significantly (p<0.05) decreased to 100.42-121.31 sec and 40.21-132.31 sec respectively in the methanol-chloroform-butanol-water and methanol-butanol treated middle aged male rats. In conclusion, this study showed that although E. longifolia Jack continued to enhance the sexual activity of the middle aged male rats by extending the duration of coitus and decreasing the refractory period between the different series of copulation, but to a smaller degree as compared to sexually active, adult male rats (Ang and Sim, 1997).

• 한국정밀공학회지
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• 제27권2호
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• pp.130-136
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• 2010

For stability analysis of the lumbar spine, the hypothesis presented is that the disc has stress sensors driving feedback mechanism, which could react to the imposed loads by adjusting the contraction of the muscles. Fusion in the motion segment of the lumbar spinal column is believed to alter the stability of the spinal column. To identify this effect finite element (FE) models combined with optimization technique was applied and quantify the role of each muscle and reaction forces in the spinal column with respect to the fusion level. The musculoskeletal FE model was consisted with detailed whole lumbar spine, pelvis, sacrum, coccyx and simplified trunk model. Vertebral body and pelvis were modeled as a rigid body and the rib cage was constructed with rigid truss element for the computational efficiency. Spinal fusion model was applied to L3-L4, L4-L5, L5-S1 (single level) and L3-L5 (two levels) segments. Muscle architecture with 46 local muscles was used as acting directions. Minimization of the nucleus pressure deviation and annulus fiber average axial stress deviation was selected for cost function. As a result, spinal fusion produced reaction changes at each motion segment as well as contribution of each muscle. Longissimus thoracis and psoas major muscle showed dramatic changes for the cases of L5-S1 and L3-L5 level fusion. Muscle force change at each muscle also generated relatively high nucleus pressure not only at the adjacent level but at another level, which can explain disc degeneration pattern observed in clinical study.