• Asian-Australasian Journal of Animal Sciences
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• v.6 no.2
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• pp.235-242
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• 1993

In order to investigate the effects of dietary cellulose and protein levels on chick performance, four semi-purified diets were formulated so as to contain cellulose at levels of 5% (LC) and 20% (HC) in combination with 10% (LP) and 20% (HP) protein, and fed ad libitum to 1-week-old White Leghorn male chicks for 3 weeks. There were no significant differences in feed intake, body weight gain and feed efficiency between the LC-HP and HC-HP groups. All parameters were lower in the LP groups; the HC-LP group consumed very small amount of feed and lost body weight during the experiment. The retention rates of DM, ash, nitrogen and energy were higher in the HP than the LP groups. The triglyceride concentration of carcass was lower in the HC-LP group and that of liver was higher in the LC-LP group. The carcass total cholesterol level was higher in the HC-HP group. The relative weight of most digestive organs was higher in the HP group irrespective of the cellulose level. In conclusion, the chick performance was primarily influenced by dietary protein level, and when the chicks were fed inadequate levels of protein, the low cellulose level gave a better performance than the high cellulose level.

• Korean Journal of Agricultural Science
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• v.47 no.1
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• pp.1-10
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• 2020

A nutrition study on weaned pigs using fermented soybean meal was done to determine the effect on growth performance, nutrients digestibility, blood profile and fecal microflora. A total of 100 weaning pigs with an initial average body weight (BW) of 8.27 ± 1.10 kg were randomly allotted into 1 of 2 dietary treatments in a 6-week feeding trial. There were 10 replicate pens in each treatment with 5 pigs per pen. The dietary treatments included: 1) control: Basal diet (CON); 2) fermented soybean meal (FSBM): Basal diet supplemented with 5% fermented soybean meal. The average daily feed intake (ADFI) was significantly improved (p < 0.05) with the dietary supplementation of the FSBM compared with the control meal during phase 2. The dietary supplementation with 5% FSBM had a significant effect (p < 0.05) on gain to feed ratio (G : F) during the overall experiment period. Collectively, the results of this study indicate that dietary supplementation of 5% fermented soybean meal improved the body weight and average daily gain (ADG), ADFI, and feed efficiency of the weaning pigs; however, there were no supplementation effects on total tract digestibility of dry matter (DM), nitrogen, energy, blood profile and fecal microflora.

• Journal of Korean Society of Water and Wastewater
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• v.22 no.3
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• pp.329-336
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• 2008

The pilot study was conducted to evaluate the applicability of air flotation(AF) processes combined with biological nutrient removal(BNR) for the retrofitting of conventional wastewater treatment facilities. The BNR system was operated in pre-denitrification and intermittent aeration; developed ceramic membrane diffusers were installed to separate the solid-liquid of activated sludge at the bottom of a flotation tank. Before performing a pilot scale study, the size distribution of microbubbles generated by silica or alumina-based ceramic membrane diffusers was tested to identify the ability of solid-liquid separation. According to the experimental results, the separation and thickening efficiency of the alumina-based ceramic membrane diffuser was higher than the silica-based ceramic membrane diffuser. In a $100m^3/d$ pilot plant, thickened and return sludge concentration was measured to be higher than 15,000mg SS/L, therefore, the MLSS in the bioreactor was maintained at over 3,000mg SS/L. The effluent quality of the AF-BNR process was 4.2mg/L, 3.7mg/L, 10.6mg/L and 1.6mg/L for $BOD_5$, SS, T-N and T-P, respectively. Lastly, it was revealed that the unit treatment cost by flotation process is lower than about $1won/m^3$ compared to a gravity sedimentation process.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.1
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• pp.91-96
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• 2006

The experiment was conducted to study the effect of choice feeding on growth performance, carcass quality, gastrointestinal development and feed utilization of 22-49 days old broilers. One hundred and forty four 22-day-old broilers were randomly allocated to 3 treatments with 4 replicates per treatment and 12 birds per replicate. Three feeding regimes are complete diet (control), ground corn and protein concentrate (treatment I), and soybean meal and balancer (treatment II). Protein concentrate is the residue part of complete diet without corn, and balancer is the residue part of complete diet without soybean meal. Treatment I and II are designed for the broilers to freely choose the two parts of diet. The results showed that: (1) broilers under choice feeding (treatment I and II) had lower performances compared with the control; (2) gastrointestinal development and the efficiency ratios that broilers converted dietary crude protein and lysine to body weight gain were improved in treatment I (p<0.05); (3) there were no significant differences in the apparent metabolizabilities of dietary dry matter, crude protein and gross energy, and deposition ratios of dietary nitrogen and energy, and carcass quality among three feeding regimes (p>0.05).

• Korean Journal of Poultry Science
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• v.25 no.2
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• pp.79-89
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• 1998

Dietary levels of single cell protein(SCP) 0 %, 5 %, 10 % and 15 % were included in experimental diets. The purpose of this experiment is to examine the effects of diets containing different levels of SCP on the performance of broiler chicks, including the nutrient availabilities, compared to that of the commercial diet. In order to evaluate the nutritive value of SCP, feeding and metabolism trial were conducted with a total of 160 broiler chicks for a period of 4 weeks. Contents of CP and pure protein in the composition of SCP were 67 % and 32. 05 %, respectively. In general, diets with over 10 % SCP substitution had significantly decreased body weight gain compared to the control diet. Feed intake of chicks fed SCP supplemental groups was significantly decreased compared to that of control, especially observed the significant difference in proportion to increas mg the levels of SCP. The feed efficiency was decreased by the addiition of SCP, but was not significantly different between control and SCP supplemental groups. The digestibilities of DM, CP and NFE tended to be similar among treatments, whereas crude fiber treated with SCP tended to be lower digestibility than control. In conclusion, the optimum dietary supplemental SCP would be less 5 % for broiler growth in this experiment.

• Journal of environmental and Sanitary engineering
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• v.23 no.4
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• pp.55-64
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• 2008

In this study, the management and improvement of public small-scale sewage treatment facilities was investigated. In order to improve the effective management of the operation of small-scale sewage treatment facilities, treatment methods and the problems associated with sewage treatment were carefully addressed based on the data and literature. The investigation results showed that sewer pipes in rural areas should be repaired to prevent sewage from leaking and small-scale operations should be required to have effective management for pollutant loads less than 50%. Also, new methods should be developed for low concentrations of sewage. A law associated with FRP treatment facilities should be established and local governments need to supervise these operations to avoid insufficient and faulty construction. It is recommended that new facilities are built with advanced treatment techniques when the old facility can not comply with nitrogen and phosphorous discharge limits. Moreover, the study shows that nutrient and coliform treatment efficiency improves when abandoned facilities are renovated with the installation of nitrification/denitrification and disinfection processes or another advanced process.

• Journal of Korean Society on Water Environment
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• v.18 no.3
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• pp.291-301
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• 2002

In this study, nutrients treatment by sequencing batch reactors(SBR) was performed. Nitrogen and phosphorus removal efficiencies were evaluated by changing SRT and mixing/aeration ratio. Not only nitrogen but also phosphorus removal patterns were investigated through track studies on 1 cycle. As SRT was fixed and mixing/aeration ratio was changed, maximum nitrogen removal efficiency was 87.6% at mixing/aeration ratio 0.67. Phosphorus removal efficiencies were more than 85.5% except no mixing condition. As mixing/aeration ratio was fixed and SRT was changed, nitrogen removal efficiencies were 70.5~79.8%, which represented slight changes, while phosphorus removal efficiencies were 49.0~97.3%, which represented sharply decreasing tendency at less than 20 day. Both phosphorus release rate k and maximum phosphorus release rate $P_{max}/M$ were are decreased as SRT was decreased, but they were not affected by mixing/aeration ratio. It was found that there is a linear relationship between ortho-phosphate uptake and maximum ortho-phosphate release.

• Korean Journal of Environmental Biology
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• v.37 no.4
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• pp.719-725
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• 2019

To recover the discoloration of Pyropia yezoensis, additional NO₃^- and PO₄^3- nutrients were supplied to the discolored blades. As a result, the efficiency of photosynthesis was increased from two days after incubation with NO₃^- and five days after incubation with PO₄^3-. In addition, the chromaticity analysis results showed significant changes. Furthermore, the cell vacuoles bloated due to discoloration were reduced again when they were restored from discoloration, suggesting that the control of discoloration is feasible by nutrient supply.

• Journal of Korean Society of Water and Wastewater
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• v.31 no.4
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• pp.357-362
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• 2017

Acetate, propionate, butyrate are the major soluble volatile fatty acids metabolites of fermented food waste leachates. This work investigate the effects of volatile fatty acid on the growth rate and $NH_4-N$, $PO_4-P$ removal efficiency of mixotrophic microalgae Chlorella vulgaris to treat digested food waste leachates. The results showed that acetate, propionate and butyrate were efficiently utilized by Chlorella vulgaris and microalgae growth was higher than control condition. Similar trends were observed upon $NH_4-N$ and $PO_4-P$ consumption. Volatile fatty acids promoted Chlorella vulgaris growth, and nutrient removal efficiencies were highest when acetate was used, and butyrate and propionate showed second and third. From this work it could be said that using mixotrophic microalgae, in this work Chlorella vulgaris, fermented food waste leachates can be treated with high efficiencies.

• Fisheries and Aquatic Sciences
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• v.11 no.4
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• pp.190-194
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• 2008

We estimated the digestibility and growth rate of juvenile olive flounder (Paralichthys olivaceus) on three diets: raw fish-based moist pellets, moist pellets, and extruded pellets. The diets were created using commercially available methods, and a basic formulated powder. A reference diet was used to compare feed digestibility and the fish growth rate achieved using the experimental diets. The apparent digestibility coefficients (ADCs) of protein for raw fish-based moist pellets and moist pellets were significantly higher (P<0.05) than those for extruded pellets and the reference diet. The ADCs of nitrogen-free extracts (NFE) of extruded pellets and moist pellets were significantly higher (P<0.05) than those for raw fish-based moist pellets and the reference diet. Fish that were fed with the raw fish-based moist pellets showed the greatest weight gain (452.4%), which was not significantly different from that of fish fed with extruded pellets (414.4%; P>0.05). These results indicate that the higher protein efficiency in fish fed with extruded pellets can result in good growth performance within flounder culture systems.