• 조명전기설비학회논문지
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• 제18권6호
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• pp.128-135
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• 2004

본 논문은 자기부상열차용 전원의 문제점을 개선시키기 위해서 다중루프 제어기를 제시하였다. 제시된 제어기는 3개의 부분으로 구성되어 있다. 첫 번째는 입력전압의 변동에 대하여 보상할 수 있는 Feed Forward제어기이며 두 번째는 리액터 전류와 출력 전류의 차를 보상하며, 세 번째는 비례적분제어기를 사용하여 출력전압에 포함된 리플을 감소시키므로써, 안정화된 시스템을 구현하였다. 이 시스템의 특성을 확인하기 위해서 Matlab Simulink와 고성능 DSP소자인 TMS320F240을 이용하여 비교 분석하였다.

• Asian-Australasian Journal of Animal Sciences
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• 제25권1호
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• pp.75-85
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• 2012

An experiment was conducted to compare the effect of the same amount of 18:2 offered either as 18:2n-6 or as a mixture of unprotected 18:2c9t11 and 18:2t10c12 on feed intake, milk components as well as plasma and milk fatty acid profile. Fifteen cows were blocked by milk yield and milk fat percentage and within block assigned randomly to 1 of 3 treatments (n = 5). Each cow passed a 12-d adjustment period (AP) on a basal diet. After the AP cows received 1 of 3 supplements during an 18-d experimental period (EP). The supplements contained either 1.0 kg ground sunflower seeds (S), 0.5 kg conjugated linoleic acid (CLA)-oil (C) or 0.75 kg of a mixture of ground sunflower seeds and CLA-oil (2:1; SC). All 3 supplements contained the same amount of 18:2 either as CLA (${\Sigma}18$:2c9t11+18:2t10c12, 1:1) or as 18:2c9c12. During the last 2 d of AP and the last 4 d of EP feed intake and milk yield were recorded daily and milk samples were collected at each milking. Blood samples were collected from the jugular vein on d 11 of AP and d 15 and 18 of EP. The 18:2 intake increased in all treatments from AP to EP. Regardless of the amount of supplemented CLA, the milk fat percentage decreased by 2.35 and 2.10%-units in treatment C and SC, respectively, whereas in the treatment S the decrease was with 0.99%-unit less pronounced. Thus, C and SC cows excreted daily a lower amount of milk fat than S cows. The concentration of trans 18:1 in the plasma and the milk increased from AP to EP and increased with increasing dietary CLA supply. While the concentration of 18:2c9t11 and 18:2t10c12 in the plasma and that of 18:2t10c12 in the milk paralleled dietary supply, the level of 18:2c9t11 in the milk was similar in C and CS but still lower in S. Although the dietary concentration of CLA was highest in treatment C, the partial replacement of CLA by sunflower seeds had a similar inhibitory effect on milk fat synthesis. Comparable 18:2c9t11 levels in the milk in both CLA treatments implies that this isomer is subjected to greater biohydrogenation with increasing supply than 18:2t10c12. The fact that unprotected 18:2t10c12 escaped biohydrogenation in sufficient amounts to affect milk fat synthesis reveals opportunities to develop feeding strategies where reduced milk fat production is desirable or required by the metabolic state of the cow.

• Fisheries and Aquatic Sciences
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• 제23권8호
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• pp.22.1-22.8
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• 2020

Background: High demand and low supply of fishmeal due to overexploitation of fisheries resources have resulted in a dramatic increase in the price of this ingredient. Olive flounder (Paralichthys olivaceus) commercial feed contains approximately 60% fishmeal and limited success has been achieved in identifying sustainable alternative protein sources for this species. Methods: An on-farm feeding trial was conducted to compare a basal diet containing 65% as the control (CONT) with two experimental diets replacing 10% of fishmeal by animal protein (AP₁₀) or 20% of fishmeal by animal and plant protein (APP₂₀). Sub-adult olive flounder averaging 327 ± 9.3 g (mean±SD) were fed one of the three diets in triplicate groups for 16 weeks. Results: Weight gain, specific growth rate, feed efficiency, protein efficiency ratio, and survival were not significantly different among fish fed all the experimental diets (P > 0.05). Also, non-specific immune responses (superoxide dismutase and lysozyme activity), serum biochemical parameters, and intestinal villi length were not significantly different among fish fed all the experimental diets (P > 0.05). Conclusions: Therefore, based on growth performance, non-specific immune responses, serum biochemical parameters, and intestinal histology, dietary animal and plant protein mixtures could replace up to 20% of fishmeal in the diet of sub-adult olive flounder.

• Animal Bioscience
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• 제34권4호
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• pp.613-620
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• 2021

Objective: This study aimed at studying the potential use of Flemingia (Flemingia macrophylla) as a protein source fodder to improve nutrients digestibility and ruminal fermentation efficiency in beef cattle. Methods: Four, Thai native beef cattle were randomly assigned in a 4×4 Latin square design. Four levels of Flemingia hay meal (FHM) were used to replace soybean meal (SBM) in the concentrate mixtures in four dietary treatments replacing levels at 0%, 30%, 60%, and 100% of SBM. Results: The experimental findings revealed that replacements did not effect on intake of rice straw, concentrate and total dry matter (DM) intake (p>0.05). However, the apparent digestibilities of DM, organic matter, crude protein, acid detergent fiber, and neutral detergent fiber were linearly increased up to 100% replacement levels. Moreover, the production of total volatile fatty acids, and propionate concentration were enhanced (p<0.05) whereas the concentration of acetate was reduced in all replacement groups. Consequently, the CH4 production was significantly lower when increasing levels of FHM for SBM (p<0.05). Furthermore, rumen bacterial population was additionally increased (p<0.05) while protozoal population was clearly decreased (p<0.05) in all replacement groups up to 100%. In addition, microbial nitrogen supply and efficiency of microbial nitrogen synthesis were enhanced (p<0.05), as affected by FHM replacements. Conclusion: The findings under this experiment suggest that 100% FHM replacement in concentrate mixture enhanced rumen fermentation efficiency, nutrients digestibilities, bacterial population, microbial protein synthesis, and subsequently reduced CH4 production in beef cattle fed on rice straw.

• Journal of Animal Science and Technology
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• 제66권2호
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• pp.398-411
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• 2024

Upregulation of the nutritional value of feed is the major target of various studies in the livestock industry, and dietary enzyme supplementation could aid in digesting the nondegrading nutrients of grains in feed ingredients. Dried distillers' grains with solubles (DDGS) is a byproduct of the fermentation process in the beverage industry and can be used as a large supply source of fiber in feed. Therefore, we conducted an experiment with male broiler chickens to investigate the effect of various types of enzymes on DDGS and compare the efficacy of single enzyme and multienzyme complexes on growth performance and gut environments in broiler chickens. We used 420 1-day-old broiler chickens (Ross 308), and they were allotted into 4 dietary treatments with seven replications (CON, corn-soybean meal [SBM] diet; NC, DDGS supplemented diet; SE, 0.05 % of mannanase supplemented DDGS-based diet; MC, 0.10% of multienzyme complex (mannanase and xylanase, glucanase) supplemented DDGS-based diet. The dietary exogenous enzyme in the DDGS-supplemented diet could improve growth performance as much as the growth of the control group, and digestibility of dry matter, crude protein, and gross energy were significantly increased by enzyme addition in groups of chicks fed DDGS-supplementation diet. Moreover, the populations of pathogenic bacteria, coliforms, and Bacteroidetes were significantly decreased by enzyme supplementation, which might lead to improved gut mucus-secreting cells and inflammatory cytokines in the jejunum. Collectively, dietary single enzyme and multienzyme complexes could improve gut environments, including intestinal immune responses and gut microbial population, and lead to improvement of growth performance in broiler chickens.

• Asian-Australasian Journal of Animal Sciences
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• 제16권2호
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• pp.248-256
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• 2003

Two experiments were conducted to determine the effects of expander processing and enzyme supplementation of wheat-based diets on growth performance and nutrient digestibility in finishing pigs. For Exp. 1, 60 finishing pigs (average initial BW of 49.5 kg) were fed meal, standard pellets and expanded pellets in a 70 d growth assay. From 49.5 to 79.0 kg, 79.0 to 111.8 kg, and overall (49.5 to 111.8 kg), ADG and ADFI were not affected by pelleting or standard vs expander conditioning (p>0.22). However, from 49.5 to 79.0 kg, pigs fed pellets have greater gain/feed than pigs fed mash (p<0.04), and pigs fed expanded pellets tended to have greater (p<0.10) gain/feed than pigs fed standard pellets. Overall (i.e. from 49.5 to 111.8 kg), gain/feed (p<0.02) and apparent fecal digestibilities of DM (p<0.001) and N (p<0.02) were improved by pelleting the diets. Also, expander processing further improved gain/feed (p<0.06) and digestibility of DM (p<0.04) compared to standard steam conditioning. Scores for keratinization (p<0.002) and ulceration (p<0.003) of the stomach were increased by pelleting, but the mean scores for the various treatments ranged only from 0.05 to 1.08 (i.e., low to mild keratosis and ulceration). For Exp. 2, 80 pigs (average initial BW of 54.1 kg) were fed mash and pellets (standard or expander) without and with xylanase. The enzyme was added to supply 4,000 units of xylanase activity/kg of diet. Adding xylanase to the mash diet improved gain/feed from 90.7 to 115.9 kg (p<0.04) of the growth assay and digestibility of DM (p<0.05) on d 39. However, in pelleted diets, adding the enzyme did not improve growth performance or digestibility of nutrients. Pelleting tended to increase scores for ulceration (p<0.06), and enzyme supplementation decreased stomach keratinization scores for pigs fed the standard pellets (p<0.01). However, as in Exp. 1, the mean scores for all treatment groups were quiet low (i.e., ranging from normal to mild). In conclusion, pelleting improved efficiency of growth, but additional benefits from expander conditioning were observed only in Exp. 1. Finally, xylanase tended to improve growth performance and nutrient digestibility, only in pigs fed mash diets but not in pigs fed pellets.

• Journal of Animal Science and Technology
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• 제59권10호
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• pp.23.1-23.11
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• 2017

Background: Although soybean meal (SBM) is excellent source of protein in diets for poultry, it is sometimes inaccessible, costly and fluctuates in supply. The SBM can partially be replaced by full-fat SBM, but the meals prepared from raw full-fat soybean contain antinutritional factors. To avoid the risk of antinutritional factors, heat treatment is always advisable, but either excessive or under heating the soybean could negatively affect the quality. However, the potential for further improvement of SBM by supplementing with microbial enzymes has been suggested by many researchers. The objective of this study was to evaluate the performance and ileal nutrient digestibility of birds fed on diets containing raw soybeans and supplemented with microbial protease. Methods: A $3{\times}2$ factorial, involving 3 levels of raw full-fat soybean (RFFS; 0, 45 or 75 g/kg of diet) and 2 levels of protease (0 or 15,000 PROT/kg) was used. The birds were raised in a climate-controlled room. A nitrogen-free diet was also offered to a reference group from day 19 to 24 to determine protein and amino acid flow at the terminal ileum and calculate the standardized ileal digestibility of nutrients. On days 10, 24 and 35, body weight and feed leftover were recorded to calculate the body weight gain (BWG), feed intake (FI) and feed conversion ratio (FCR). On day 24, samples of ileal digesta were collected at least from two birds per replicate. Results: When RFFS was increased from 0 to 75 g/kg of diet, the content of trypsin inhibitors was increased from 1747 to 10,193 trypsin inhibitors unit (TIU)/g of diets, and feed consumption of birds was also reduced (P < 0.05). Increasing RFFS level reduced the BWG from hatch 0 to 10 d (P < 0.01) and hatch to 24 d (P < 0.05). The BWG of birds from hatch to 35 was not significantly (P = 0.07) affected. Feed intake was also reduced (P < 0.05) during 0 to 35 d. However, protease supplementation improved (P < 0.05) the BWG and FCR during 0 to 24 d. Rising levels of RFFS increased the weight of pancreas (P < 0.001) and small intestine (P < 0.001) at day 24. Except for methionine, apparent and the corresponding standardized ileal digestibility of CP and AA were reduced (P < 0.01) by increasing levels of RFFS in diets. Conclusion: This study showed that some commercial SBM could be replaced by RFFS in broiler diets, without markedly compromising productivity. The AID and SID of CP and lysine were slightly improved by dietary supplementation of microbial protease.

• 한국가금학회지
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• 제32권2호
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• pp.101-106
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• 2005

산란노계를 닭고기로서 자원화하여 농가의 수익과 단백질 공급원으로 활용하기 위한 목적으로, 생산성이 낮고 경제적 가치가 적은 산란노계 사료에 목초액을 첨가${\cdot}$급여하여 육질 개선 효과를 조사하기 위하여 계획하였다. 이사브라운 갈색종 240수를 배치하여 대조구에는 육계용 배합사료, 시험 1구에는 국산 목초액 $0.8\%$, 시험 2구에는 외국산 목초액 $0.4\%$를 첨가하여 급여하였다. 사료 섭취량은 대조구가 시험구보다 3g 정도 적었는데 목초액의 유기산이 사료의 소화에 영향을 준 것으로 사려된다. 사육성적의 차이는 국산과 외국산 목초액의 구성성분의 차이에 기인하며, 외국산 목초액의 첨가는 성페르몬과 성분이 유사한 목초액이 내분비 물질의 분비를 촉진한 결과 산란율이 증가하였고, 목초액의 첨가에 따라 조지방 함유량은 다리 고기가 가슴고기보다 많았으며 육색의 개선 효과도 있었다. 다리고기의 육질과 관능검사는 근섬유의 조직을 가늘게 하고 보습력을 증가시키는 외국산 목초액 첨가구에서 좋은 평가를 받았다.

• 한국가금학회지
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• 제30권4호
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• pp.281-287
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• 2003

Monacolin-K가 0.6% 들어있는 Monascus 배양물을 시판 산란계 시료에 각각 0.00%, 2.67%, 5.33% 및 8.00%씩 추가로 첨가하여, 1일 1사당 사료섭취량이 125g일 경우 1일1수당 Monacolin-K 섭취량이 각각 0, 20, 40 및 60mg이 되도록 하는 4개 처리를 두었고, 총 180수의 산란계를 공시하여 10주간 사양시험을 실시한 결과 산란율과 평균 난중은 처리간에 유의적인 차이가 없었으나, 사료섭취량과 산란량 kg당 사료 요구율은 Monascus 배양물의 첨가수준이 증가할수록 감소하였다. 전 기간 평균 혈청 콜레스테롤 함량은 Monascus 배양물의 첨가수준이 증가할수록 감소하는 경향이었으나, 유의적인 차이는 없었다. 난황의 콜레스테롤 함량은 Monascus 배양물 첨가급여 4~5주 후부터 유의적으로 감소하였고(P<0.05), 사양시험 종료시 대퇴부근육의 콜레스테롤 함량도 유의적으로 감소하였다(P<0.05).

• 한국가금학회지
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• 제30권2호
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• pp.101-106
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• 2003

육용종계 산란기의 적정 단백질공급수준을 구명하기 위하여 종계형 케이지에 아바에이카 육용종계 400 수를 공시하여 40 주간(24∼64주령) 1일 1수당 단백질 급여량을 18, 20 22, 24g 수준으로 사양시험을 실행하였으며 그 결과는 다음과 같다. 1) 총 산란율과 종란 산란율은 모두 처리간에 유의적인 차이가 있었으며(P<0.05), 20g 공급구가 가장 높았으나 18∼22g 공급구간에는 유의차가 없었고 24g 공급구는 20g 공급구에 비해 유의적으로 낮았다{P<0.05). 2) 평균난중은 l 일 단백질공급수준이 증가할수록 증가하는 경향이었으나{P<0.05), 20∼24g 공급구간에는 유의차가 없었고 18g 공급구만 24g 공급구와 유의적인 차이가 있었다. 성계생존율은 처리간에 유의적인 차이가 없었다. 3) 계란 kg당 또는 계란 l개당 사료요구율과 ME요구량은 모두 l일 CP 20g 공급구가 가장 우수했으며(P<0.05), 계란 kg당 사료요구율과 ME 요구량에서는 CP 18g 공 급구 계란1개당 사료요구율과 ME요구량에서는 CP 24g 공급구만 CP 20g 공급구와 유의차를 보였다(P＜0.05). 4) 계란 kg당 또는 계란 l개당 CP 요구량은 모두 l일 단백질공급량이 많아질수록 증가하였으내(P<0.05), 18g과 20g공급구간에는 유의차가 없었다. 5) 계란 kg당 또는 계란 1개당 사료비는 모두 CP 20g공급구가 가장 우수하였으나(P<0.05), 계란 l개당 사료비는 18∼20g 공급구간에 유의차가 없었다. 이상의 결과로 육용종계 산란기의 산란율과 난중, 사료와 영양소이용효율 및 사료비용에서 1일 단백질공급량은 20g이 적정수준이었다.