• 제목/요약/키워드: Optimal Feeding

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A Review of the Optimum Feeding Rates and Feeding Frequency in Korean Rockfish Sebastes schlegeli Reared at Seven Different Water Temperatures

  • Mizanur, Rahman M.;Bai, Sungchul C.
    • Fisheries and Aquatic Sciences
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    • v.17 no.2
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    • pp.229-247
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    • 2014
  • Seven feeding trials were conducted to determine the effects of feeding rate and frequency in the Korean rockfish Sebastes schlegeli at seven different water temperatures. Two feeding-rate experiments for 5-g Korean rockfish at $17^{\circ}C$ and $20^{\circ}C$; three feeding rate experiments for 16-g Korean rockfish at $16^{\circ}C$ and $24^{\circ}C$; and finally, two feeding frequency experiments for 93- and 100-g at $15^{\circ}C$ and $20^{\circ}C$ were conducted. Twenty fish averaging $5.5{\pm}0.2$ g ($mean{\pm}SD$) were randomly distributed into 18 indoor tanks containing 40-L seawater from a semi-recirculation system. Fish were fed a commercial diet for 4 weeks at water temperatures of $17^{\circ}C$ and $20^{\circ}C$. Two feeding trials were conducted to determine the optimum feeding frequency in growing Korean rockfish reared at temperatures of $15^{\circ}C$ and $19^{\circ}C$. Broken line regression analysis of weight gain (WG) indicated that the optimum feeding rates of 5-g growing Korean rockfish were 4.48% (BW/day; BW, body weight) at $17^{\circ}C$ and 4.83% (BW/day) at $20^{\circ}C$. Broken line regression analysis of WG showed optimum feeding rates of 16-g juvenile Korean rockfish of 3.41% (BW/day) at $16^{\circ}C$, 3.75% (BW/day) at $20^{\circ}C$, and 3.34% (BW/day) at $24^{\circ}C$. The biological performance, results, along with morphological indices and serological characteristics, suggest that a feeding frequency of 1 meal/day was optimal to improve WG in growing Korean rockfish grown from 93 to 133 g at a water temperature of $15^{\circ}C$, and 100 to 132 g at $19^{\circ}C$.

Effect of Different Feeding Frequency on the Growth Performance, Hematological Parameters and Body Nutrient Composition of Juvenile Chum Salmon Oncorhynchus keta Reared in a Recirculating Aquaculture System (순환여과양식시스템에서 사료 공급 횟수가 연어(Oncorhynchus keta) 치어의 성장, 체조성 및 혈액성분에 미치는 영향)

  • Kyu-Seok Cho;Seok-Woo Jang;Yu-Jin Lee;Seunghyung Lee
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.56 no.5
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    • pp.734-740
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    • 2023
  • The effect of feeding frequency on growth performance, body nutrient composition, and hematological parameters of juvenile chum salmon Oncorhynchus keta was investigated. The juveniles (10.9±0.3 g) were fed commercial feed for 30 days with feeding frequencies of 1, 2, 3, 4, or 5 meal (s)/day (n=2 tanks per treatment) in a recirculating aquaculture system (RAS). Fish were fed to satiation at each of the feeding frequencies. At the end of the feeding trial, final body weight, weight gain, and specific growth rate of fish fed 2 meals/day were significantly higher than those of fish fed 1 meal/day(P<0.05); however, no difference was detected among the other feeding frequencies. Daily feed intake significantly increased with increasing feeding frequency, whereas feed and protein utilization efficiencies continuously decreased with increase in the feeding frequency. Among the treatments, fish fed 1 meal/day showed the lowest value in whole-body lipid content and total protein concentration in plasma. Taken together, the optimal feeding frequency for growth performance and feed utilization efficiency in chum salmon juveniles reared in the RAS was determined to be 2 meals/day.

Bioreactor Operating Strategy in Scultellaria baicalensis G. Plant Cell Culture for the Production of Flavone Glycosides (Flavonoid 배당체 생산을 위한 Scutellaria baicalensis G. 식물 세포 배양에서 생물반응기 운전전략)

  • 최정우;조진만;이정건;이원홍;김익환;박영훈
    • KSBB Journal
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    • v.13 no.3
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    • pp.259-267
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    • 1998
  • Optimal feeding strategies in bioreactor operation of Scutellaria baicalensis G. plant cell culture were investigated to maximize the production of flavone glycosides by using a structured kinetic model which can predict culture growth and flavone glycosides synthesis in a rigorous, quantitative manner. For the production of baicalin and wogonin-7-0-GA, the strategies for glucose feeding into Scutellaria baicalensis G. plant cell culture were proposed based on the model, which are a periodic fed-batch operation with maintenance of cell viability and of specific production rate respectively, and a perfusion operation with maintenance of specific production rate for baicalin and wogonin-7-0-GA. Simulation results showed that the highest volumetric concentration of flavone glycosides was obtained in a periodic fed-batch operation with maintenance of cell viability among all the suggested strategies. In the periodic fed-batch operations, the higher volumetric production of flavone glycosides was achieved compared with that in the perfusion operation. It can be concluded that a periodic fed-batch operation with maintenance of cell viability would be the optimal and practical operating strategy of Scutellaris baicalensis G. plant cell culture for the production of flavone glycosides.

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Study on Dressing Conditions for Creep-feed in Cubic Boron Nitride Grinding of OrthoMTA Compacters (OrthoMTA 컴팩터의 크리프피드 CBN 연삭을 위한 드레싱 조건 연구)

  • Maeng, Heeyoung;Baek, Eun-Pyo
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.23 no.1
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    • pp.69-74
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    • 2014
  • An OrthoMTA compacter is made by machining a Ni-Ti alloy wire using tapered helix creep-feed grinding machines. This aim of this study is to find the optimal dressing conditions to sharpen the corner of a cubic boron nitride (CBN) wheel. On the basis of the results of various experiments, it is verified that the most important factors in dressing are the dressing depth and feeding method, whereas the feed rate has less importance for producing a smaller corner R value. The study also finds the optimum dressing depth to reduce the dressing time, a feeding speed and method to stabilize the machining, and the mesh grade for the CBN wheel to make the groove of the compacter deeper.

Production of Single-Cell Protein on Petroleum Hydrocarbon (석유탄화수소를 이용한 단세포단백질의 생산에 관한 연구 3)

  • 변유량;권태완
    • Korean Journal of Microbiology
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    • v.9 no.3
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    • pp.95-102
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    • 1971
  • The growth characteristics of Candida tropicalis KIST 351 on gas oil substrate under different culture conditions were investigated and the preliminary animal feeding experiments using this yeast as a partial substitute of fish meal was also conducted. The yeast assimilates effectively n-paraffins in gas oil ranging from $C_{16}$ to $C_{16}$ with its maximum cell growth at $33^{\circ}C$ and pH 5.5 with aeration of 3 vvn and agitation of 900 rpm. The optimal concentrations of nitrogen sources, $HK_2PO_4$ and $Na_2HPO$ were 4, 2 and 0.5g/1, respectively. Ferrous sulfate, manganese sulfate and zinc sulfate showed positive effect to cell growth with the optimal range of 5-10 ppm. In the feeding experiment with 3 and 5% incorporation of the gas oil grown yeast, neither adverse effects on growth of chicks nor toxic effect were observed. Protein content of the dried cell was 58.8% and its amino acid composition compared well with other single-cell protein products and FAO reference protein.

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Practical diagnostic technique for catenary surge arrester in electric railway (전차선로용 피뢰기 진단기법 적용 연구)

  • Han, Moon-Seob;Jang, Dong-Uk;Jung, Ho-Sung;Kil, Gyung-Suk
    • Proceedings of the KIEE Conference
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    • 2005.07b
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    • pp.1631-1633
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    • 2005
  • This paper describes the measurement result of leakage current flowing arrestors connected in catenary line to propose an optimal management methods. 27 arrestors set in 7 locations were tested. The leakage currents are included a harmonics of electric train during the operation of electric train in feeding section and in case of feeding earthing system.

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Optimal Dietary Protein and Lipid Levels for Growth of Juvenile Israeli Carp Cyprinus carpio

  • Aminikhoei, Zahra;Choi, Jin;Lee, Sang-Min
    • Fisheries and Aquatic Sciences
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    • v.18 no.3
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    • pp.265-271
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    • 2015
  • A feeding trial of four dietary protein levels (20, 30, 40, and 50%) and two lipid levels (7 and 14%) with a factorial design was conducted to determine the optimal dietary protein and lipid levels for juvenile Israeli carp Cyprinus carpio. Triplicate groups of fish (average body weight, $1.3{\pm}0.02g$) were fed the experimental diets for 9 weeks. Survival of fish was not affected by either dietary protein or dietary lipid level. Weight gain and feed efficiency increased as dietary protein levels increased up to 40 and 50%, respectively. Weight gain was higher in fish fed the high-lipid diets with 20 and 40% protein content. Feeding efficiency increased as the dietary lipid level increased for the 30, 40, and 50% protein diets. Daily feed intake decreased with increasing protein level and the minimum feed consumption was observed in fish fed the 50% protein diet with 14% lipid content. Moisture and lipid contents of the whole body were affected by both dietary protein and lipid levels. The crude lipid content of fish fed the 14% lipid diet was higher than that of fish fed the 7% lipid diet at each protein level. The results of this study indicate that a diet containing 40% protein with 14% lipid content is optimal for the growth and effective protein utilization of juvenile Israeli carp.

Effects of Nonnutritive Sucking on Behavioral State in Preform Infants (비영양 흡철의 미숙아 행동상태에 대한 효과)

  • Shin Hee Sun
    • Child Health Nursing Research
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    • v.4 no.2
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    • pp.305-313
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    • 1998
  • The purpose of study was to examine the effect of nonnutritive sucking(NNS) on behavioral state in preform infants. Fourteen infants (gestational age 28-35 weeks, M=31.86 ; birth weights 1095-2275g, M=1694g) admitted to NICU, serving as their controls were randomly administered 5 min of nonnutritive sucking and a control condition. Behavioral state was measured using the Anderson Behavioral State Scale(ABSS). Heart rates were obtained for each infant before and during NNS and bottle feeding. Data collecction was done by 3 experienced nurses in NICU 2 times a day for conseculive 4 days for each subject. Interrater reliability were .80-.90. The findings were as follows : 1. Preform infants averaged active restless states 58.93% in the prointervention phase and 27.32% in the NNS phase. Inactive awake states were 3.57% in the preintervention phase and 34.64% in the NNS phase. 2. There were significantly more positive changes to inactive awake states for the NNS intervention, Z=-2.35, p=.01. 3. There was no statistically significant difference in heart rate change between NNS intervention and control condition, z=-1.15, p=.24. 4. The rates of feeding success determined by finishing prescribed amount of milk by bottle feeding within 15 minutes were 83.94% in NNS intervention and 89.29% in control condition. The findings from this study confirmed that NNS is effective for behavioral state modulation and inducing optimal state for feeding in preform infant. The NNS intervention in nursing practice may help the transition of preform infants for nipple feeding.

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Optimization of Round Bar Forging Process by Using Finite Element Analysis (유한요소해석을 이용한 환봉 단조공정 최적화)

  • 최성기;천명식;문영훈
    • Transactions of Materials Processing
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    • v.13 no.2
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    • pp.142-147
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    • 2004
  • Three-dimensional rigid-plastic finite element analysis has been performed to optimize open die forging process to make round bar. In the round bar forging, it is difficult to optimize process parameters in the operational environments. Therefore in this study, finite element method is used to analyze the practice of open die forging, focusing on the effects of reduction, feeding pitch and rotation angle for optimal forging pass designs. The soundness of forging process has been estimated by the smoothness and roundness of the bar at various combination of feeding pitches and rotation angles. From the test result, process conditions to make round bar having precise dimensional accuracy have been proposed.

Degradation of 4-Chlorophenol by a Photo-Fenton Process with Continuous Feeding of Hydrogen Peroxide (과산화수소 연속주입식 광펜톤산화공정에 의한 4-염화페놀 분해연구)

  • Kim, Il-Kyu
    • Journal of Korean Society of Water and Wastewater
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    • v.27 no.1
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    • pp.31-38
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    • 2013
  • The degradation of 4-chlorophenol(4-CP) by various AOPs(Advanced Oxidation Processes) with continuous feeding of $H_2O_2$, including the ultraviolet/hydrogen peroxide, the Fenton and the photo-Fenton process has been investigated. The photo-Fenton process showed the highest removal efficiency for degradation of 4-chlorophenol than those of other AOPs including the Fenton process and the combined UV process with continuous feeding of $H_2O_2$. In the photo-Fenton process, the optimal experimental condition for 4-CP degradation was obtained at pH 3. Also the 4-CP removal efficiency increased with decreasing of the initial 4-CP concentration. 4-chlorocatechol and 4-chlororesorcinol were identified as photo-Fenton reaction intermediates, and the degradation pathways of 4-CP in the aqueous phase during the photo-Fenton reaction were proposed.