• Title/Summary/Keyword: Lighting Performance

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Effect of Dietary Oligosaccharides on the Performance, Intestinal Microflora and Serum Immunoglobulin Contents in Laying Hens (Oligosaccharides 계열 생균제가 산란계의 생산성, 장내 미생물 및 혈청 면역 글로불린 함량에 미치는 영향)

  • Kim, C.H.;Shin, K.S.;Woo, K.C.;Paik, I.K.
    • Korean Journal of Poultry Science
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    • v.36 no.2
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    • pp.125-131
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    • 2009
  • This study was conducted to investigate the effects of dietary supplementation of mannan-oligosaccharides (MOS) and fructo-oligosaccharides (FOS) on the performance, immune response and small intestinal microflora in laying hens. A total of 960 Hy-Line $Brown^{(R)}$ laying hens of 27 wks old, housed in 2 bird cages, were assigned in a completely randomized block design into one of the following 6 dietary treatments: control, antibiotic (6 ppm avilamycine), 0.025% MOS, 0.05% MOS, 0.25% FOS, and 0.5% FOS. Each treatment had 4 replicates of 40 birds and was fed ad libitum for 6 wks under 16 h lighting regimen. There were significant differences among treatments in hen-day and hen-housed egg production. Hen-day egg production in 0.025% MOS was significantly higher than that of control. Hen-housed egg production in antibiotic-treated group was significantly higher compared with control. Egg weight, feed intake and feed conversion were not significantly different among treatments. Egg shell thickness was highest in 0.25% FOS, but was not significantly different among the rest of treatments. There were no significant differences among treatments in egg shell strength, egg shell color, egg yolk color and Haugh unit. IgG concentrations in serum were not significantly different among treatments. On the other hand, IgA concentrations of the treated birds tended to be increased compared with control. Dietary treatments tended to decrease Cl. perfringens and E. coli, and to increase Lactobacillus spp. The result of this experiment showed that dietary supplementation of MOS and FOS in laying hens tended to improve egg production comparable to the supplementation of antibiotics. The level of serum IgA and small intestinal microflora were also significantly affected by the treatments.

Effects of Dietary Supplementation of Copper-soy Proteinate on the Performance of Laying Hens (Copper-soy Proteinate의 첨가가 채란계의 생산성에 미치는 영향)

  • Lee, Mun-Ku;Kim, Chan-Ho;Shin, Dong-Hun;Jung, Byoung-Yun;Paik, In-Kee
    • Korean Journal of Poultry Science
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    • v.38 no.3
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    • pp.165-171
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    • 2011
  • This study was conducted to investigate the effects of dietary supplementation of copper-soy proteinate (Cu-SP) on the performance of laying hens. A total of 1,000 Hy-Line Brown laying hens of 32 wks old were assigned to one of the following 5 dietary treatments: Control, Cu-SP 50, 100, 150, 200 (50, 100, 150, 200 ppm Cu supplementation as Cu-soy proteinate). Each treatment was replicated 4 times with fifty birds per replication, housed in 2 birds cages. Fifty birds units were arranged according to randomized block design. Feeding trial lasted 5 wks under 16L : 8D lighting regimen. There were no significant differences among treatments in hen-day and hen-house egg production, egg weight, broken & soft egg production. Feed intake and feed conversion rate (FCR) were significantly (P<0.01) lower in Cu-SP treated groups than Control. Eggshell thickness was significantly (P<0.01) higher in Control than Cu-SP 100, 150 and 200. Egg yolk color index was significantly (P<0.01) higher in Cu-SP 200 than other treatments. Egg shell color index was significantly (P<0.05) higher in Cu-SP 150 and Cu-SP 200 than Cu-SP 100. Concentration of copper, iron and zinc of the egg yolk were not significantly influenced by treatment. There were no significant differences in the level of leukocytes and erythrocytes in the chicken blood. The result of this experiment showed that dietary supplementation of Cu-SP at the level of 50ppm of Cu can reduce feed intake and FCR.

Effect of Dietary Supplementation of Cu-methionine Chelate and Cu-soy Proteinate on the Performance, Small Intestinal Microflora and Immune Response in Laying Hens (사료내 Cu-methionine Chelate와 Cu-soy Proteinate가 산란계의 생산성, 소장내 미생물 균총 및 면역체계에 미치는 영향)

  • Paik, I.K.;Kim, C.H.;Park, K.W.
    • Korean Journal of Poultry Science
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    • v.35 no.3
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    • pp.303-311
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    • 2008
  • This study was conducted to investigate the effect of dietary supplementation of Cu-methionine chelate(Cu-Met) and Cu-soy proteinate(Cu-SP) on the performance, small intestinal microflora and immune response in laying hens. A total of 960 Hy-line $Brown^{(R)}$ laying hens of 39 wks old were assigned to one of the following 6 dietary treatment: control(C), antibiotic(Avilamycine 6 ppm), Cu-Met 50 and Cu-Met 100(50 and 100 ppm Cu as Cu-methionine chelate), Cu-SP 50 and Cu-SP 100(50 and 100ppm Cu as Cu-soy proteinate). Each treatment was replicated 4 times with forty birds per replication, housed in 2 birds per cages. Forty birds units were arranged according to randomized block design. Feeding trial lasted 6 wks under 16 hours lighting regimen. Hen-day and hen-house egg production of groups treated with Antibiotic and Cu supplements tended to be higher than the control with significant difference (P<0.05) shown between Cu-Me 100 and control. Egg weight was significantly (P<0.05) heavier in antibiotic and Cu-SP treatments than Cu-Met treatments but they were not significantly different from the control. Eggshell strength, egg shell thickness, egg yolk color and Haugh unit were not significantly different among treatments. There were no significant differences in leukocytes and erythrocytes in the chicken blood. But mean corpuscular hemoglobin value(MCH) was significantly (P<0.05) higher in Cu-SP 100 than antibiotic treatment. The concentrations of serum IgG and IgA were not significantly different among treatments. Copper concentration in the liver tended to increase as the level of copper supplementation increased, that of Cu-SP 100 being significantly (P<0.05) higher than those of the control and antibiotic treatment. Concentrations of iron and zinc of the liver were not significantly influenced by treatments. Populations of Cl. perfringens and Lactobacilli in the small intestinal content were significantly (P<0.05) influenced by treatments. Population of Cl. perfringens decreased and that of Lactobacilli increased in the copper supplemented groups. The result of this experiment showed that Cu-Met and Cu-SP are comparable to antibiotic in improving egg production in laying hens. Birds fed diets supplemented with Cu-SP produced heavier eggs than those fed diets with Cu-Met. There were no significant differences in the performances between 50 ppm and 100 ppm copper supplementation as organic forms.

Effect of Supplementary Herbs and Plant Extracts on the Performance of Laying Hens (허브 및 식물 추출물의 급여가 산란계의 생산성에 미치는 영향)

  • Kim, C.H.;Paik, I.K.
    • Korean Journal of Poultry Science
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    • v.35 no.1
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    • pp.71-78
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    • 2008
  • This study was conducted to investigate the effects of dietary supplementation of herbs and plant extracts (PE) on the performance, small intestinal microflora and immune response in laying hens. A total of 1,440 Hy-Line Brown laying hens of 67 wks old were assigned to one of the following 9 dietary treatments : T1 : Control (C), T2 : C + Avilamycine 6 ppm, T3 : C + Herb $Mix^{(R)}$ 0.2%, T4 : C + Biostrong $510^{(R)}$ 0.02%, T5 : C + $APEX^{(R)}$ 0.02%, T6 : C + $Digestarom^{(R)}$ 0.02%, T7 : C + $Phellozyme^{(R)}$ 0.1%, T8 : C + $Galicin^{(R)}$ 0.05%, T9 : C + CRINA $Poultry^{(R)}$ 0.05%. Each treatment was replicated 8 times with twenty birds housed in 2 bird cages. Twenty bird units were arranged according to completely randomized block design. Feeding trial lasted 6 wks under 16 hours lighting regimen. Hen-day egg production was not significantly different among the treatments, but that of supplemented groups tended to be higher than the control. There were significant differences among treatments in feed intake and feed conversion ratio. Feed intake was higher in the supplemented groups than the control. Feed conversion ratio was higher in T8 than other treatments. Egg shell color index and egg yolk color index were significantly different among treatments. Egg shell color was affected by supplements and egg yolk color index of T9 (PE-CRINA) was significantly higher than the control. Haugh unit was not significantly different among treatments. There were significant differences in leukocytes and erythrocytes parameters. The level of serum WBC and stress index (heterophil/lymphocyte) were higher in supplemented groups than the control. The level of RBC tended to be lower in the herb or PE groups than the control. The concentration of serum IgG was not significantly different among the treatments, but all those of the supplemented groups were higher than the control. The number of Lactobacilli spp. tended to increase and that of Cl. perfrigens decrease in the supplemented groups. The number of E. coli significantly decreased in the supplemented groups. The results of this experiment showed that feeding herbs and plant extracts to laying hens tended to improve the egg production and affect positively on the level of blood parameters and small intestinal microflora.

Effects of Dietary Supplementation of Vitamin C and Sea Buckthorn on the Performance and Meat Quality in Old Laying Hens (비타민 C와 비타민나무 부산물 첨가가 산란 성계의 생산성 및 계육 품질에 미치는 영향)

  • Kang, Hwan Ku;Kim, Ji-Hyuk;Hwangbo, Jong;Kim, Chan Ho
    • Korean Journal of Poultry Science
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    • v.42 no.2
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    • pp.181-189
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    • 2015
  • The objective of this study was to investigate the effect of dietary supplementation of vitamin C and Sea buckthorn on the performance, blood biochemistry and meat quality in old laying hens. A total 200 Hy-Line Brown laying hens (101 weeks old) were randomly allotted to 1 of 5 dietary treatments : (1) Basal : basal diet, (2) Vit. C : basal diet + 0.1% vitamin C, (3) SB 0.1 : basal diet + 0.1% Sea buckthorn, (4) SB 0.5 : basal diet + 0.5% Sea buckthorn, and (5) SB 1.0 : basal diet + 1.0% Sea buckthorn. Each treatment was replicated 4 times with 10 birds units were arranged according to randomized block design. Feeding trial lasted 4 weeks under 16L:8D lighting regimen. The diets were fed to hens on an ad libitum basis for 4 weeks. Result indicated that during feeding trial of the experiment, hen-day egg production and feed conversion ratio were not significantly influenced by treatments. However, feed intake was significantly (P<0.05) higher in Vit. C and SB treated groups than the basal during 1 wks and 3 wks. Egg weight was significantly (P<0.05) higher in basal and Vit. C than the SB 1.0 treatment. There were no differences in carcass yield during feeding trials. However, partial ratio (breast and neck) was significantly (P<0.05) higher in SB 0.5 than other treatment. There were no differences in the level of leukocytes and erythrocytes. There were no significant differences on proximate analysis (DM, crude protein, crude fat, and crude ash), meat color, water holding capacity, cooking loss, and fatty acids concentrations. In conclusion, dietary supplementation of vitamin C and Sea buckthorn to the diet of old laying hens might be a potential ingredient for increasing partial weight (breast) in old laying hens.

Effects of Single or Mixed Supplementation of Bacterial Phytase and Fungal Phytase on Laying Performance and Nutrient Digestibility (Bacterial 및 Fungal Phytase의 단일 및 혼합 급여가 산란계의 생산성과 영양소 이용에 미치는 영향)

  • Kang, H.K.;Park, S.Y.;Yu, D.J.;Kim, J.H.;Kang, G.H.;Na, J.C.;Kim, D.W.;Suh, O.S.;Lee, S.J.;Lee, W.J.;Kim, S.H.
    • Korean Journal of Poultry Science
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    • v.35 no.2
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    • pp.137-142
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    • 2008
  • This study was conducted to investigate the effect of single or mixed supplementation of bacterial and fungal phytase using 45-wk-old 450 Hy-Line Brown laying hens housed in individual cages for 12-wk period. The birds were reallocated to have similar egg productivity by examining the egg production for one wk before starting the experiment. Two sources of phytase, bacterial (BP) and fungal (FP), were used either in single or mixture to determine the effects of these phytase. Five dietary treatments consisted of control (BP 0, FP 0), T1 (BP 300, FP 0), T2 (BP 300, FP 300), T3 (BP 300, FP 3000), and T4 (BP 0, FP 3000). The DPU was used for phytase activity in this experiment. The nonphytate phosphorus (NPP) content of control was 0.30%, and those of phytase treatments were set to 60% of the Control. Experimental diets were fed ad libitum throughout the experimental period. The lighting schedule of 17L7D was employed. The egg production was not different between control and bacterial phytase treatments, but the T4 showed significantly low productivity compared to control (P<0.05). No difference was found in average egg weight among all treatments. The daily egg mass did not show any statistical differences among all treatments: however, it was significantly low in T4 compared to ther control during the latter half of the experiment (P<0.05). No significant difference was found among treatments in terms of feed intake, feed conversion and egg quality. The digestibilities of dry matter, crude protein, and fat digestibility were similar regardless of the treatments. No significant trends were detected in Ca and P availability. In conclusion, the BP level of 300 DPU contributed to achieve 40% reduction of recommended nonphytate phosphorus addition. The synergistic effect of bacterial and fungal phytase was not confirmed.

Effect of Various β-1,3-glucan Supplements on the Performance, Blood Parameter, Small Intestinal Microflora and Immune Response in Laying Hens (β-Glucan 제제들이 산란계의 생산성, 혈액 성상과 소장내 미생물 균총 및 면역 체계에 미치는 영향)

  • Park, K.W.;Rhee, A.R.;Lee, I.Y.;Kim, M.K.;Paik, I.K.
    • Korean Journal of Poultry Science
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    • v.35 no.2
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    • pp.183-190
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    • 2008
  • This study was conducted to investigate the effect of feeding diets supplemented with ${\beta}-glucan$ products on the performance, small intestinal microflora and immune response in laying hens. The ${\beta}-glucan$ products used in the experiment were $BetaPolo^{(R)}$ ; soluble ${\beta}-glucan$ of microbial cell wall origin, $HiGlu^{(R)}$ ; microbial cell wall origin, $OGlu^{(R)}$ ; oat origin, $BGlu^{(R)}$ ; barley origin. A total of 720 Hy-Line Brown laying hens of 40wks old were divided into 5 dietary treatments : T1 ; Control( C), T2 ; $BetaPolo^{(R)}$, T3 ; $HiGlu^{(R)}$, T4 ; $OGlu^{(R)}$, T5 ; $BGlu^{(R)}$. Each treatment was replicated 4 times with 36 birds/replicate housed in 2 bird cages, and arranged according to completely randomized block design. Feeding trial lasted 40ds under 16 h lighting regimens. There were significant differences among treatments in hen-house egg production feed intake and feed conversion. HiGlu treatment was significantly higher than OGlu treatments in hen-house egg production. ${\beta}-glucan$ supplemented treatments were lower than the control in feed intake and feed conversion ratio. All ${\beta}-glucan$ supplemented treatments were significantly higher than the control in eggshell strength. Eggshell color and Haugh unit tended to be lower in the supplemented group than the control. IgY concentration was not significantly affected by treatments. At $5^{th}$ week of experiment, however, IgY concentration tended to increase in the supplemented groups. Among the leucocytes parameters, WBC, heterophil, lymphocytes, monocyte and eosinophil concentration were lower in the supplemented groups than those of the control. Among erythrocytes, HCT(hematocrit) and MCV(mean corpuscular volume) were significantly affected by treatment. MCV of supplemented groups were higher than that of the control. Immunoglobulin concentrations in the birds were not significantly different among treatments. However, IgA concentration tended to be low in the supplemented groups than the control. The cfu of small intestinal microflora were not significantly different among treatments, but that of Cl. perfringens tended to be lower than the control. The result of this experiment indicateted that feeding ${\beta}-glucan$ to laying hens improve feed conversion ratio and eggshell strength. Also intestinal microflora and immune responses are modified.

New Approaches for Overcoming Current Issues of Plasma Sputtering Process During Organic-electronics Device Fabrication: Plasma Damage Free and Room Temperature Process for High Quality Metal Oxide Thin Film

  • Hong, Mun-Pyo
    • Proceedings of the Korean Vacuum Society Conference
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    • 2012.02a
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    • pp.100-101
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    • 2012
  • The plasma damage free and room temperature processedthin film deposition technology is essential for realization of various next generation organic microelectronic devices such as flexible AMOLED display, flexible OLED lighting, and organic photovoltaic cells because characteristics of fragile organic materials in the plasma process and low glass transition temperatures (Tg) of polymer substrate. In case of directly deposition of metal oxide thin films (including transparent conductive oxide (TCO) and amorphous oxide semiconductor (AOS)) on the organic layers, plasma damages against to the organic materials is fatal. This damage is believed to be originated mainly from high energy energetic particles during the sputtering process such as negative oxygen ions, reflected neutrals by reflection of plasma background gas at the target surface, sputtered atoms, bulk plasma ions, and secondary electrons. To solve this problem, we developed the NBAS (Neutral Beam Assisted Sputtering) process as a plasma damage free and room temperature processed sputtering technology. As a result, electro-optical properties of NBAS processed ITO thin film showed resistivity of $4.0{\times}10^{-4}{\Omega}{\cdot}m$ and high transmittance (>90% at 550 nm) with nano- crystalline structure at room temperature process. Furthermore, in the experiment result of directly deposition of TCO top anode on the inverted structure OLED cell, it is verified that NBAS TCO deposition process does not damages to the underlying organic layers. In case of deposition of transparent conductive oxide (TCO) thin film on the plastic polymer substrate, the room temperature processed sputtering coating of high quality TCO thin film is required. During the sputtering process with higher density plasma, the energetic particles contribute self supplying of activation & crystallization energy without any additional heating and post-annealing and forminga high quality TCO thin film. However, negative oxygen ions which generated from sputteringtarget surface by electron attachment are accelerated to high energy by induced cathode self-bias. Thus the high energy negative oxygen ions can lead to critical physical bombardment damages to forming oxide thin film and this effect does not recover in room temperature process without post thermal annealing. To salve the inherent limitation of plasma sputtering, we have been developed the Magnetic Field Shielded Sputtering (MFSS) process as the high quality oxide thin film deposition process at room temperature. The MFSS process is effectively eliminate or suppress the negative oxygen ions bombardment damage by the plasma limiter which composed permanent magnet array. As a result, electro-optical properties of MFSS processed ITO thin film (resistivity $3.9{\times}10^{-4}{\Omega}{\cdot}cm$, transmittance 95% at 550 nm) have approachedthose of a high temperature DC magnetron sputtering (DMS) ITO thin film were. Also, AOS (a-IGZO) TFTs fabricated by MFSS process without higher temperature post annealing showed very comparable electrical performance with those by DMS process with $400^{\circ}C$ post annealing. They are important to note that the bombardment of a negative oxygen ion which is accelerated by dc self-bias during rf sputtering could degrade the electrical performance of ITO electrodes and a-IGZO TFTs. Finally, we found that reduction of damage from the high energy negative oxygen ions bombardment drives improvement of crystalline structure in the ITO thin film and suppression of the sub-gab states in a-IGZO semiconductor thin film. For realization of organic flexible electronic devices based on plastic substrates, gas barrier coatings are required to prevent the permeation of water and oxygen because organic materials are highly susceptible to water and oxygen. In particular, high efficiency flexible AMOLEDs needs an extremely low water vapor transition rate (WVTR) of $1{\times}10^{-6}gm^{-2}day^{-1}$. The key factor in high quality inorganic gas barrier formation for achieving the very low WVTR required (under ${\sim}10^{-6}gm^{-2}day^{-1}$) is the suppression of nano-sized defect sites and gas diffusion pathways among the grain boundaries. For formation of high quality single inorganic gas barrier layer, we developed high density nano-structured Al2O3 single gas barrier layer usinga NBAS process. The NBAS process can continuously change crystalline structures from an amorphous phase to a nano- crystalline phase with various grain sizes in a single inorganic thin film. As a result, the water vapor transmission rates (WVTR) of the NBAS processed $Al_2O_3$ gas barrier film have improved order of magnitude compared with that of conventional $Al_2O_3$ layers made by the RF magnetron sputteringprocess under the same sputtering conditions; the WVTR of the NBAS processed $Al_2O_3$ gas barrier film was about $5{\times}10^{-6}g/m^2/day$ by just single layer.

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Studies about Acceptance of Songs or Sounds 'Sori(唱)' appeared in Musical Comedy performed in Korean Traditional Music and Changeable Aspects Thereof - Centering around Korean Musical Group, Taroo - (국악뮤지컬에 나타난 소리(창(唱))의 수용 및 변화양상 연구 - "'국악뮤지컬집단 타루'를 중심으로" -)

  • Jung, Hyewon
    • Journal of Korean Theatre Studies Association
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    • no.49
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    • pp.5-47
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    • 2013
  • Among the styles of performing arts, perhaps the genre that has attracted the largest audience would be musical. Popularity of musical has brought diverse changes in our performing arts market, and, upon emerging another musical genre, called 'Korean Traditional Musical Comedy,' it has been well-received by the audiences. 'Korean Traditional Musical Comedy' is a word that are formed by merging two other terms such as 'Korean Traditional Music' and 'Musical (Comedy).' In the meantime, however, it has yet some problems in order to be defined as the genre that has concrete concepts. It is because the term such as Korean Traditional Musical Comedy was created being closely associated with a marketing purpose rather than a term that defines the characteristics of a genre of performing arts. Although this new musical genre has drawn attentions of many audiences by adding 'Musical Comedy' to 'Korean Traditional Music' that was not quite popular to the public, it still does not have any established forms so that there is a fine line between "Korean Traditional Musical Comedy" and another genre like traditional style folk opera ("Changgeuk"). Looking at the characteristics of the musical work called 'Korean Traditional Musical Comedy, in general, first of all, it is a performance where music and drama are played. Here, the distinctive characteristic of this musical is that 'Korean Traditional Music' is sung. And the kinds of Korean traditional musics being sung are mainly Pansori (dramatic story-singing) and folk-songs, and, in most cases, Korean traditional musical instruments are being used as accompanying music. In this paper, the researcher investigated the aspects of experiment centering around Korean Musical Group, Taroo. These days, various experiments has been repeated not only for the works of Taroo but other musical work presently called 'Korean Traditional Musical Comedy' also. Having encompassed overall performance factors including use of musical instruments, dance, acting, materials for drama as well as music in drama, the researcher has gone through experiments repeatedly. Meanwhile, however, the subject matters that make 'Korean Traditional Musical Comedy' mostly attractive to the audiences are music and songs or sounds. ["Sori" also called "Chang" (唱)] Particularly, under the current situation of our musicals, the role of "Sori" is extremely important. The factor that plays absolutely most important role in acceptance and transformation of "Sori" is the created Pansori. Since the created Pansori is composed with new rhythmic patterns and new narrative poems, it tells the present story. Also it draws good responses from the audiences owing to easy conveyance of dialogues. And, its new style brings diversification to organization of musical instruments, so then this leads to the arrangements of music for Korean traditional music instruments, as well as instrumental music ensemble, orchestra, and jazz band, etc. Likewise, upon appearing creative musics in 'Korean Traditional Musical Comedy,' professional music and vocal compositions have begun to emerge naturally. And, the song specialist and writer, of course, staffs including direction, lighting, and sounds, etc are required. That is, professional composition method are forced to be introduced to all areas. Other than this, there are many music pieces which are based on our unique songs and sounds ("Sori") and such traditional factors as use of lead singer for ceremony or chorus, and the method that puts weight on Pansori. Accordingly many things accomplished. However, it is required that 'Korean Traditional Musical Comedy' go through numerous discussions and more experiments. Above all, the most important things are the role of actor and actress, and their changes, and training of actor and actress further. Good news is there are good audience responses. 'Korean Traditional Musical Comedy' is an open genre. As musicals are divided into several domains according to the characteristics thereof, 'Korean Traditional Musical Comedy' will be able to show its distinctive features in various styles according to embodiment.

Effect of Photoperiod Considering Animal Welfare for Growth Ability and Blood Properties in Broiler Chicks (동물복지를 고려한 점등시간이 육계 병아리의 성장 능력 및 혈액 성상에 미치는 영향)

  • Kim, Hee-Jin;Son, Jiseon;Jeon, Jin-Joo;Kim, Hyun-Soo;Kang, Hwan-Ku;Lee, Woo-Do;Yun, Yeon-Seo;Hong, Eui-Chul
    • Korean Journal of Poultry Science
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    • v.49 no.3
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    • pp.139-144
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    • 2022
  • This study was conducted to investigate the effect of three different photoperiods on growth performance, blood properties, and stress indicators in broiler chicks between 1-7 days after hatching. Two hundred and fifty-two 1-day-old male broiler chicks (57.0±0.12 g) were divided into three treatments, with 4 replicates per treatment and 22 birds per replicate subjected to three different photoperiods of 24L, 22L/2D and 18L/6D. A light-emitting diode bulb served as the light source, with an illuminance of 30 lx. As an experimental diet, a commercial feed based on a corn-soybean meal, with 22% CP and 3,150 kcal/kg ME diet, and water were fed ad libitum. Body weight gain, feed conversion ratio, and liver weight ratio showed a statistically significant difference between the 18L/6D and 24L treatments (P<0.05), but with no significant difference between the 22L/2D treatment and either the 24L or 18L/6D treatment. The breast meat ratio was 5.59% in the 18L/6D treatment group, which was lower than that of other treatment groups (P<0.05). The triglyceride levels were highest (P<0.05) in the 18L/6D treatment among treatments, but alanine aminotransferase levels were significantly higher (P<0.05) in the 22L/2D treatment than in the 24L treatment. Levels of cytokines, i.e., Interleukin-6 and Tumor Necrosis Factor-α did not show a significant difference among the treatments, but corticosterone content was significantly higher (P<0.05) in the 24L treatment than in the 18L/6D treatment. In conclusion, 22 hours of lighting is appropriate between 1~7 days after hatching, considering growth performance and the overall health of broiler chicks.