• Asian-Australasian Journal of Animal Sciences
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• 제22권5호
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• pp.747-755
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• 2009

The feed resource for animals is a major cost determinant for profitability in livestock production enterprises, and thus any effort at improving the efficiency of feed use will help to reduce feed cost. Feed conversion ratio, expressed as feed inputs per unit output, is a traditional measure of efficiency that has significant phenotypic and genetic correlations with feed intake and growth traits. The use of ratio traits for genetic selection may cause problems associated with prediction of change in the component traits in future generations. Residual feed intake, a linear index, is a trait derived from the difference between actual feed intake and that predicted on the basis of the requirements for maintenance of body weight and production. Considerable genetic variation exists in residual feed intake for cattle and pigs, which should respond to selection. Phenotypic independence of phenotypic residual feed intake with body weight and weight gain can be obligatory. Genetic residual feed intake is genetically independent of its component traits (body weight and weight gain). Genetic correlations of residual feed intake with daily feed intake and feed conversion efficiency have been strong and positive in both cattle and pigs. Residual feed intake is favorably genetically correlated with eye muscle area and carcass weight in cattle and with eye muscle area and backfat in pigs. Selection to reduce residual feed intake (excessive intake of feed) will improve the efficiency of feed and most of the economically important carcass traits in cattle and pigs. Therefore, residual feed intake can be used to replace traditional feed conversion ratio as a selection criterion of feed efficiency in breeding programs. However, further studies are required on the variation of residual feed intake during different developmental stage of production.

• 한국응용과학기술학회지
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• 제28권1호
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• pp.6-9
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• 2011

Step feed process was analyzed stoichiometrically for the optimal operation conditions in this study. In case of optimal operation conditions, minimum R (sludge recycling) value, r (internal recycling ratio) value, and n (influent allocation ratio) value for the step feed process to acquire the maximum TN removal efficiency were identified by theoretical analysis. Maximum TN removal efficiency, based on stoichiometric reaction, can be obtained by controlling n value for the step feed process.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2002년도 학술대회지
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• pp.95-98
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• 2002

Three-dimensional flow analyses for two different ratios of radius to height of sedimentation bed are implemented to evaluate the effect of blockage ratio of center feed wall and angle of distributor on sedimentation efficiency, and to find the optimal value of those parameters. Sedimentation efficiencies for three different shapes are compared with and without rotation speed. And then, five different combinations of blockage ratio of center feed wall and angle of distributor are compared It reveals that the effect of blockage ratio of center fled wall and angle of distributor is considerable to sedimentation efficiency while rotation effect can be neglected and $0.55 and 33^{\circ}$for blockage ratio of center food wall and angle of distributor, respectively, ive the best sedimentation efficiency.

• 대한화학회지
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• 제21권2호
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• pp.125-131
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• 1977

Imitation milk는 식물성유(soy milk)에 식물성유(油), 탄수화물, whey powder, Nacascinate, 필수아미노산, 비타민, 무기물 등을 배합 가공한 것이다. Spray dried 방법으로 제조한 imitation milk의 feed efficiency ratio 및 영양가 측정은 Albino Rat의 사육시험과 화학적분석 방법으로 측정하였다. 지방산과 아미노산의 각 성분조성은 Gaschromatography 및 Amino Acid Autoanalyzer로 분석하였다. 이 연구 결과를 고찰하여 보면 필수아미노산과 고도불포화지방산이 feed efficiency ratio에 큰 영향을 미친것을 확인할 수 있다.

• Fisheries and Aquatic Sciences
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• 제8권3호
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• pp.128-131
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• 2005

The effects of alternate-week feeding strategies on growth and feed efficiency ratio of juvenile Nile tilapia were investigated in a recirculating aquaculture system. Twenty fish initially weighing 25.5 g were randomly distributed into each of 18 tanks to conduct three replicates for each of six different feeding strategies. Weight gain of fish in the control that were fed daily for 6-week feeding trial was significantly higher than those of fish subjected to various alternate-week feeding regimes. Weight gain of fish that were starved for 3 weeks and then fed daily for 3 weeks (3WS+3WF) was not significantly different from that of fish, starved and fed daily for alternate 1-week period during the trial (1WS+1WF), but was significantly higher than those of fish starved for 2 weeks, and fed for 2 weeks (2WS+2WF); fish starved for 4 weeks and fed for 2 weeks (4WS+2WF); and fish fed for 5 weeks and fed for 1 week (5WS+1WF.) The amount of feed supplied to fish in the groups of 1WS+1WF and 3WS+3WF was significantly lower than that fed to fish in the control group, but significantly higher than the amount feed supplied to fish in the other three groups. Feed efficiency ratio for fish in the control group did not differ from that for fish in the groups of 1WS+1WF, 2WS+2WF and 3WS+3WF, but was significantly higher than that for fish in the groups of 4WS+2WF and 5WS+1WF. In conclusion, juvenile Nile tilapia that were subject to starvation for 1 to 5 weeks did not exhibit compensatory growth sufficient to attain the same weight as fish fed daily for 6 weeks. In addition, fish subjected to starvation exhibited low feed efficiency ratio compared to fish fed daily, which were probably attributable to poor weight gain.

• 대한본초학회지
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• 제21권1호
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• pp.1-7
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• 2006

Objectives: To find out the effects GGT1, an antiobestic drug widely used clinics, has on the amount of feed intake, the amount of change in the body weight and the food efficiency ratio using the data from the hGHTg obese male rats. Also, to evaluate in terms of antiobestic effects, the difference between GGT1 and reductil (sibutramine), which has been approved by the FDA of the United States. Methods: We measured the change in body weight and the amount of feed intake for 8 weeks by categorizing the hGHTg obese male rats into three groups: the control group, the GGT1 group, and the reductil (RD) group. We also evaluated the antiobestic effect by calculating the food efficiency ratio, which is the increase of bodyweight divided by the amount of feed intake. Results: In case of body weight, moderate slope of the curve in the graph of GGT1 group could mean that the weight is decreasing as time flows. In case of food efficiency ratio, the p-value was 0.745 in a test for determining if an interaction exists between the group and the point of measurement, meaning that it does not exist; also, the p-value in a test for the effect of level of repetition in food efficiency ratio according to the point of measurement equaled 0.002. Conclusion: The drug-treated groups had a greater inhibitory effect in feed intake than the control group. The results showed the food efficiency ratio had a tendency to decrease. The GGT1 group in particular was under a greater effect than the RD group.

• Preventive Nutrition and Food Science
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• 제1권2호
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• pp.239-243
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• 1996

Three hundred and twenty-four 1 day old chicks were used to determine the effects of fat source and energy to protein ratio on growth performance , carcass composition and the efficiency on nutrient utilization. Chicks were assigned. in a completely randomized design, to 3*3 factorial arrangement of treatments. Chicks received one of three fat sources (n0 fat, tallow, corn oil) and one of three energy to protein ratios(16, 14 and 12kcal ME/g CP). All diets were formulated to be isocaloric(3.2Mcal ME/kg diets) using published ME values for the diet ingredients. Addition of tat to the diet increased ADG, average daily feed intake, and gain to feed, Chicks fed diets containing fat had increased percentage body DM and ether extract(EE), but percentage CP was not different, Chicks fed diets containing fat had increased efficiency of protein and energy deposition. Addition of fat ad either fallow or corn oil yielded similar results. Reducing the energy to protein ratio of the diet did not affect ADG or gain to feed, but tended to decrease average daily feed intake(p=0.80), as well as resulting in linear(p<0.05) reductions in body percentage DM., EE and also total EE. Increasing the energy to protein ratio did not affect percentage or total body Cp. Adding fat to poultry diets improved growth performance and the efficiency of growth chicks. Decreasing the energy to protein ratio did not affect growth performance, but reduced EE in the body of Chicks.

• Asian-Australasian Journal of Animal Sciences
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• 제21권11호
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• pp.1629-1634
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• 2008

A trial was conducted to determine the effect of low crude protein (CP) diets with constant metabolizable energy to crude protein (ME:CP) ratio on growth, body composition and nutrient utilization of broiler chicks from 1 to 26 days of age. Four dietary treatments having four levels of CP and ME as 23, 22, 21 and 20% and 3,036, 2,904, 2,772 and 2,640 kcal/kg, respectively, were formulated and a ME:CP ratio of 132 was maintained in all the diets. Digestible lysine was maintained at 1.10 of the diet. A total of 1,760 day-old Hubbard broiler chicks were randomly divided into 16 experimental units and each diet was offered to four experimental units at random. Feed intake was increased (p<0.05) while weight gain and feed conversion ratio were adversely affected (p<0.05) when the diets with low CP and ME were fed to broilers. Total protein intake and total ME intake were linearly decreased (p<0.05) and protein efficiency ratio and energy efficiency ratio were lower (p<0.05) than in the chicks fed dietary regimen with 22% CP and 2,904 kcal/kg ME. The whole body analysis of the birds revealed that chicks fed the lowest dietary regimens retained less (p<0.05) nitrogen and more ether extract than chicks fed the control diet, however, body dry matter, total body ash and fat free body protein were not affected. Similarly, protein and energy utilization were also unaffected by the dietary treatments. In summary, chicks fed low CP diets with constant ME:CP ratio grew slower, used feed less efficiently and retained less protein and more body fat than chicks fed the control diet.

• 한국수산과학회지
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• 제42권4호
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• pp.349-353
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• 2009

Two feeding trials were conducted to evaluate the soybean meal as a substitute for the fish meal in diet (experiment I), and experimental practical diet and commercial diet (experiment II) for growth of far eastern catfish. In the experiment I, three replicate groups of juveniles (average weight 7.2 g) were fed one of diets containing 0, 10 and 20% soybean meals for 66 days. Survival and final mean weight were not significantly affected by dietary soybean meal levels. No significant differences were observed in feed efficiency, protein efficiency ratio and protein retention of fish fed between 0% (control diet) and 20% soybean meal diets. However, fish fed 10% soybean meal diet showed the lower feed efficiency, protein efficiency ratio and protein retention, and higher daily feed intake compared with fish fed control diet and 20% soybean meal diet. The contents of moisture, crude protein, crude lipid and ash in the whole body were not significantly affected by dietary soybean meal levels. In the experiment II, three replicate groups of juveniles (average weight 7.3 g) were fed either the formulated diet or commercial diet for 66 days. Survival and final mean weight were not significantly different among treatment. Significantly higher feed efficiency, protein efficiency ratio and protein retention, and lower daily feed intake were observed in fish fed experimental practical diet compared with fish fed commercial diet (P<0.05). Proximate compositions of the whole body were not significantly affected by diets. The results of these studies suggest that soybean meal can be used as a substitute for fish meal up to 20% in diet, and the dietary formulation used in the experiment II could be applied to the practical feed for far eastern catfish.

• 한국양식학회지
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• 제19권2호
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• pp.95-98
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• 2006

This study was performed to determine possibility of compensatory growth of juvenile olive flounder fed a commercial feed during the summer season. Five treatments of fish with triplicates were prepared: C, S1, S2, S3 and S4. Fish in the control group (C) was hand-fed with the commercial feed to apparent satiation twice daily for 6 days a week during 6 weeks. Fish in S1, S2, S3, and S4 experienced 1, 2, 3, and 4 weeks of starvation before fed to satiation twice daily for 5, 4, 3, and 2 weeks, respectively. The feeding trial lasted far 6 weeks. Survival of flounder in C, S1 and S2 was significantly (P<0.05) higher than that offish in S4. Weight gain and specific growth rate (SGR) of flounder in C and S1 were significantly (P<0.05) higher than those of fish in S2, S3 or S4. And weight gain and SGR of flounder in S2 and S3 were significantly (P<0.05) higher than those of fish in S4. Feed consumption of flounder tended to increase with weeks of feeding. Feed efficiency ratio and protein efficiency ratio for flounder in C, S1, S2 and S3 were significantly (P<0.05) higher than those for fish in S4. Moisture content of the whole fish in C was lowest, but highest for fish in S4, respectively. Crude protein content of the whole fish in C was highest, but lowest far fish in S4, respectively. Crude lipid content of the whole fish in C, S1 and S2 was significantly (P<0.05) higher than that of fish in S4. In conclusion, full compensatory growth was obtained in juvenile olive flounder fed for 5 weeks after 1-week feed deprivation during the summer season. Compensatory growth of fish was well supported by improvement in feed efficiency ratio and protein efficiency ratio.