• 한국수의병리학회지
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• 제7권1호
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• pp.27-41
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• 2003

The purpose of this study was to evaluate the effect of a subsequent infection of porcine reproductive and respiratory syndrome(PRRS) virus to pigs with A. pleuropneumonia in pigs. Twenty three 7-weeks-old commercial pigs were infected with PRRS virus and/or A. pleuropneumoniae serotype 5 intratracheally. Feed conversion, clincal signs, gross and histopathological lesions and immunohistochemical findings were examined. 1. Feed conversion ratio in dual-infected pigs with PRRS virus and A. pleuropneumoniae were higher than that of single- infected pigs with PRRS virus or A. pleuropneumoniae. 2. Dual-infected pigs with PRRS virus followed by A. pleuropneumoniae showed more severe clinical signs and gross, histopathological and immunohistochemical pulmonary lesions. The results indicated that dual infections with PRRS virus and A. pleuropneumoniae caused more severe respiratory lesions and growth retardation in pigs than single infection with PRRS virus or A. pleuropneumoniae.

• Korean Chemical Engineering Research
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• 제47권6호
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• pp.700-704
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• 2009

GTL(gas-to-liquid) 합성유 제조용 SCR(steam carbon dioxide reforming) 공정의 시뮬레이션 연구를 수행하였다. 온도 및 $CH_4/steam/CO_2$ 반응물 비와 같은 변수를 바꾸어 가면서 SCR 공정을 위한 최적 운전조건을 살펴보았다. 공정 시뮬레이션을 위해 Aspen Plus를 사용하였다. 또한 정상상태 가정하의 열역학적 물성치 계산을 위해 Aspen Plus의 RSK (Redlich-Kwong-Soave) 상태방정식을 사용하였다. FT 공정을 위한$H_2/CO$ 비, $CH_4$ 전환율, $CO_2$ 전환율을 살펴봄으로써 최적의 온도와 최적의 반응물 비를 결정하였다. 시뮬레이션 결과, SCR reformer 촉매층 출구 최적온도는 상압에서 $850^{\circ}C$ 였으며, 이 온도에서 $CH_4$ 전환율은 99%, $CO_2$ 전환율은 49%로 계산되었고, $CH_4/steam/CO_2$ 최적 반응물 비율은 1.0/1.6/0.7로 나타났다.

• 한국임상수의학회지
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• 제30권5호
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• pp.353-358
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• 2013

본 연구는 오배자(Galla Rhois, GR)가 이유자돈의 성장과 설사발생에 미치는 영향을 조사하였다. 100두의 28일령 이유자돈을 무작위적으로 5개의 실험군(NC, 대조군; PC, chlortetracycline 0.3 g/kg feed; GR 1, GR 1.0 g/kg feed; GR 2, GR 2.0 g/kg feed; GR 3, GR 4.0 g/kg feed3)으로 나누어 실험을 수행하였다. 28일 동안 실험군별로 처리한 후, PC, GR 2 그리고 GR 3의 최종 체중과 사료요구율은 NC와 비교하여 통계적으로 유의성 있게 증가하였다(p < 0.05). 또한, PC와 GR를 급여한 모든 군의 일평균증체량과 일평균사료섭취량도 NC와 비교하여 통계적으로 유의한 차이를 보였다(p < 0.05). 특히, GR 2와 GR 3의 최종 체중, 일일평균증체량, 일평균사료섭취량 그리고 사료요구율은 PC와 비교하여 유의한 차이를 보이지 않았다. 분변지수와 설사지속시간에 있어서, PC와 GR를 급여한 모든 군이 NC와 비교하여 통계적으로 유의한 차이를 나타내었다(p < 0.05). 혈액학적 그리고 혈액생화학적 분석 결과, NC와 GR를 급여한 모든 군들 사이에서 혈액학적 그리고 혈액생화학적 지표값들의 통계학적 유의한 차이가 보이지 않았다. 본 연구결과로부터, GR은 자돈에 있어서 설사발생과 성장증체를 개선시키기 위한 강력한 사료첨가제로 사료된다.

• 공업화학
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• 제25권2호
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• pp.204-208
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• 2014

본 연구는 1차원 반응기 모델을 이용한 수치 시뮬레이션을 통해 수소투과량, 수소선택도, 사용된 촉매의 양, 급송흐름에서의 $H_2O/CO$ 조성비 및 Ar sweep gas가 막반응기(membrane reactor)에서의 수성가스전이반응의 성능에 미치는 영향을 분석하였다. 막반응기에서 평형상태보다 향상된 수소수율을 얻기 위해선 적어도 100 이상의 수소선택도를 가져야 함이 관찰되었으며, 수소투과량이 계속 증가될 경우에는 수소수율의 증가폭이 점차 감소됨이 보였다. 낮은 수소투과량의 경우에는 촉매량이 증가할수록 초기엔 증가된 CO 전환율을 보이다가 점차 그 증가폭이 감소되었으며, 높은 수소투과량의 경우에는 촉매의 양과 무관하게 높은 CO 전환율이 관찰되었다. 급송흐름에서의 $H_2O/CO$ 조성비가 1.5 이상인 경우엔 수소투과량이 막반응기에서의 CO 전환율에 미치는 영향이 미미하였고, 막반응기에서 평형상태보다 향상된 CO 전환율을 얻기 위해선 적어도 $6.7{\times}10^{-6}mol\;s^{-1}$ 의 Ar 몰유속이 필요함이 밝혀졌다.

• Asian-Australasian Journal of Animal Sciences
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• 제18권10호
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• pp.1457-1463
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• 2005

In this research, the possibilities of using canola meal (CM) in place of soybean meal (SBM), and also the effects of multi-enzyme and phytase supplementation on the performance of quails were investigated. For this purpose, soybean meal (44% CP), canola meal (37% CP), phytase (produced from Peniophora luci) and multi-enzyme ($\beta$-glucanases, pectinases, cellulases and hemicellulases) were used. CM was used supplying 0, 25 and 50% of CP from SBM and each of the phytase and multi-enzyme blends were added to the each level. This study was conducted with 675 day old quails (Coturnix coturnix Japonica) in 9 groups with 3 replicates including 25 birds (mixed sex) per replicate. Nine isocalaric and isonitrogenous diets were prepared. The effects of enzymes and CM levels were studied with a 3${\times}$3${\times}$3 factorial arrangement for three CM levels (0, 25 and 50%), three treatments (without enzyme, phytase enzyme and multi-enzyme) and three replicates. While the 25% CM level did not affect the liveweight gain 50% CM level decreased the liveweight gain (p<0.05). Multi-enzyme addition to the 50% CM group increased the liveweight gain compared to the other groups (p<0.05). CM levels and enzyme supplementation had no effect on feed consumption, feed conversion ratio, dressing percentage, viability, tibia ash content, Ca and P contents of tibia ash, viscera weight, gizzard weight and length of growth period. While heart weight and liver weight were not affected by CM levels, but they were affected by enzyme supplementation. CM levels and enzyme supplementation did not affect final liveweight, feed consumption, feed conversion ratio, egg yield, egg weight, shell weight and shell index during laying period. The increase in the CM level lightened the colour of the yolk (p<0.05).

• Asian-Australasian Journal of Animal Sciences
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• 제19권2호
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• pp.198-202
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• 2006

An experiment was conducted to investigate the effect of phytase, organic acids and their interaction on body weight gain, feed consumption, feed conversion ratio, carcass yield and tibia ash. A total of 680 three-day old Japanese quail chicks (Coturnix coturnix japonica) were assigned to 20 battery brooders, 34 chicks in each. The experimental period lasted 35 days. The treatment groups employed were: 1) a positive control which included 3.5 g available phosphorus (AP)/kg diet and 10 g Ca/kg diet; 2) a negative control which included 2 g AP/kg diet and 8 g Ca/kg diet, 3) negative control diet supplemented with either 300 FTU phytase/kg diet (phytase) or 4) 2.5 g organic acid (lactic acid+formic acid)/kg diet (organic acid); or 5) 300 FTU phytase/kg diet+2.5 g organic acid/kg diet (phytase+organic acid). All birds were fed with the positive control diet for a week and then transferred to the dietary treatments. At the end of the study, there were no differences (p>0.005) among the groups in body weight, weight gain, feed consumption, feed conversion ratio and carcass yield. Tibia ash, however, was reduced (p<0.001) for quails fed the negative control diet containing a low-level of AP compared to the positive control diet containing adequate AP. The addition of phytase, organic acid or phytase+organic acid to the diets containing the low-level of AP improved (p<0.001) tibia ash. On the other hand, an extra synergistic effect of phytase and organic acid on tibia ash was not determined. This study demonstrated that it may be possible to reduce supplemental level of inorganic P with phytase and/or organic acid supplementation for quail diets without adverse effect on performance and tibia ash.

• 한국가금학회지
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• 제28권1호
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• pp.61-67
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• 2001

Two experiments were conducted to evaluate the dietary supplemental fruit extract(Bio-plus) on performance and intestinal microflora of broiler chicks. Seven treatments were allocated into control, 0.05, 0.10, 0.20, 0.10, 0.20, 0.40, 0.80, 1.60% with four replications for five weeks, in both experiments. Diets contained 21.5% CP, 3, 100 kcal/kg ME for the rest two weeks. Weight gain, feed intake, feed conversion ratio(FCR) were weekly measured. Birds were sacrificed to examine the E. coli and Salmonella from cecum and ileum at the end of experiment. In experiment 1, Weight gain of Bio plus treatments tended to increase compared to that of control, but was not consistency between them. Chicks fed Bio-plus showed significantly lower feed conversion ratio(FCR) than control(P〈0.05). In experiment 2, Weight gain of Bio plus treatments was significantly different from control(P〈0.05) for starting period and linearly increased upto 0.80% for the rest of two weeks, but was not significantly different. Feed intake of chicks fed Bio-plus tended to be higher than control. Bio-plus treatments was not statistically different FCR from control. ND titer showed no significance, but tended to be higher in Bio-plus treatments than control. The number of ileum salmonella was significantly decreased in Bio-plus treatments compared to that of control in expt 2 (P〈0.05). Total yeast and Lactobacillus spp. of illeum tended to increase in expt 1 and were significantly higher in expt 2 than control(P〈0.05). The results of these experiment indicated that dietary Bio-plus supplements increased weight gain, the number of ileum yeast and Lactobacillus spp. of broiler chicks.

• 한국가금학회지
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• 제26권4호
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• pp.237-245
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• 1999

This study was conducted to investigate the effect of dietary thyroid hormone (T$_3$and T$_4$) on growth, feed conversion ratio and serum T$_3$or T$_4$concentration of broiler chicks. Zero to six week-old broiler chicks were randomly allocated into seven treatment groups for feeding trials with three replication : control, T$_3$(0.1), T$_3$(1.0), T$_3$(5.0), T$_4$(0.1), T$_4$(1.0), T$_4$(5.0) ppm group. Concentrations of T$_3$and T$_4$in serum were analyzed. The weight gain of T$_3$(1.0), T$_3$(5.0) and T$_4$(5.0) groups were significantly lower than that of control. No statistically significant adverse effect was observed in other groups (p〉0.05). Feed intake was significantly lower in T$_3$(0.1, 1.0 and 5.0) and T$_4$(5.0) than in control group (p〈0.05), and the feed conversion ratio had a similar trend to the feed intake change. The contents of liquid and abdominal fat pad in carcass were significantly decreased in all T$_3$and T$_4$groups (p〈0.05). T$_3$and T$_4$concentration in serum was significantly increased at over 1.0ppm of the hormone supplementation level. As T$_3$addition level increased, T$_4$concentration in serum reduced ; however, T$_3$in serum was directly proportional during fasted were slightly increased when T$_3$or T$_4$was added to broiler diets.

• 농업과학연구
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• 제38권4호
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• pp.659-665
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• 2011

This work was conducted to evaluate the hatching and growing performance of Korean Native Ducks (KND) Pure Breeding Line (PL). A total of 400 male and female pullets were produced from PL to keep in National Institute of Animal Science, Korea. Pullets were divided into 4 treatments, 5 repetitions per treatment, and 20 heads per repetition. Four treatments were compared in a $2{\times}2$ factorial arrangement with 2 groups (White strains, WW; Jade Green strains, CC) for their parents and 2 groups (male and female). Livability was not significantly different at 20 weeks among male and female of 2 strains. There was no significant difference on body weight and feed intake between WW and CC strains (P>0.05), but there was significantly different on body weight and feed intake between male and female (P<0.05). The feed conversion ratio of female was higher compared to male (P<0.05), but there was no significantly different between CC and WW strains. These results provide the basic data to develope the new strains of Korean Native Ducks.

• Journal of Animal Science and Technology
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• 제64권6호
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• pp.1077-1091
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• 2022

This study was conducted to determine the rumen fermentation dynamics of lupin flakes and elucidate the effects of lupin flake supplementation on the growth performance, blood metabolites, and carcass characteristics of Hanwoo steers. In vitro and in situ trials of lupin grains and lupin flakes were conducted using three Hanwoo cows with rumen fistulas. The feeding trial included 40 early-fattening Hanwoo steers randomly divided into four groups: control, T1, T2, and T3. Their formula feed contained 0%, 3%, 6%, and 9% lupin flakes, respectively. In vitro rumen pH and ammonia concentrations were lower in the lupin flake group than in the lupin grain group after 6 and 24 h of incubation, respectively (p < 0.05). Concentrations of propionate, butyrate, and total volatile fatty acids were higher in the lupin flake group than in the lupin grain group after 12 h of incubation (p < 0.05), as was the crude protein disappearance rate at 9 and 12 h of rumen fermentation (p < 0.05). Supplementation with lupin flakes did not affect the average daily gain. Compared to that in the control group, dry matter intake was lower in the lupin flake-supplemented groups (p < 0.05); the feed conversion ratio was lower in T2 and T3 (p < 0.05); and plasma total protein concentration in 29-month-old steers was lower in T1 and T3 (p < 0.05). Plasma triglyceride concentration was lower in the lupin flake-supplemented groups than in the control group (p < 0.05). The incidence rate of yield grade A was higher in T1 and T2 than in the control group; the incidence rate of meat quality 1⁺ grade or higher was highest in T2. The carcass auction price was higher in T2 than in the other groups. Overall, compared to whole lupin grains, lupin flakes seem to more substantially affect rumen ammonia concentrations and crude protein disappearance rate. Additionally, we suggest that supplementation with 6% lupin flake formula feed exerts positive effects on the feed conversion ratio, yield grade, and quality grade of Hanwoo steers.