• Fisheries and Aquatic Sciences
• /
• v.12 no.4
• /
• pp.317-323
• /
• 2009

Waste products were biologically estimated from juvenile flounder (Paralichthys olivaceus) on three diet types-raw fish-based moist pellets, moist pellets, and extruded pellets. Total solid and soluble wastes were estimated by determining nutrient digestibility and accumulation in juvenile flounders through growth trials. Total solid wastes produced were 20%-23% of the organic matter supplied. Soluble excretions ranged from 45% to 49%. Soluble nitrogenous excretions ranged from 36.4% to 46.2%. These results indicate that about 30.2%-35.9% of supplied feed is retained in the fishes' bodies while the remainder of feed is excreted into culture systems or the surrounding environment.

• Analytical Science and Technology
• /
• v.28 no.3
• /
• pp.196-203
• /
• 2015

Selenium species (inorganic selenium, selenoaminoacids, and selenoproteins) were analyzed using anion exchange and affinity chromatography, which were connected to ICP/MS for the blood serum of sows fed by seleniumfortified feed. The Anion Exchange PRP X-100 column was used for the analysis of inorganic selenium (Se⁴⁺ and Se⁶⁺) and selenoaminoacids. The HEP column was used to separate SelP from GPx+SeAlb in selenoproteins. A quantitative analysis was performed using the post-column isotope dilution technique. The lactating sows were divided into three groups and fed by selenium fortified feed (organic 0.3 mg/kg, 0.6 mg/kg and inorganic 0.6 mg/kg) for four weeks. The test groups showed increases in selenoaminoacids compared with the control group, except the inorganic feed group. There was no significant difference between the organic feed groups. All test groups showed increases in selenoproteins. In particular, SelP showed a large increase that was 1.5 times higher than the other proteins.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.22 no.5
• /
• pp.509-516
• /
• 2021

This study investigated the effect of dietary supplementation with cysteamine hydrochloride (CSH) on the growth performance and nutrient digestibility of broilers. A total of 180 one-day-old male Ross broilers were allotted to one of the three treatment groups with three replications (20 birds per replication). The experimental groups were as follows: control group (basal diet), CSH-1 group (basal diet + 250 mg CSH/kg feed), and CSH-2 group (basal diet + 500 mg CSH/kg feed). During the grower period, feed intake, body weight, average daily gain, feed conversion ratio (FCR), and livability did not show any variation among the treatment groups. On the other hand, a comprehensive evaluation of the finisher period and the entire experiment period found that FCR was significantly improved in CSH-1 and CSH-2 groups as compared to the control group (p<0.05). The dietary supplementation of CSH did not affect the carcass and meat percent (breast and leg muscle). Although there was no significant difference, the digestibility of organic matter tended to be higher in the CSH-2 group than in the control group (p<0.1). This study suggests that a dietary supplement with 250-500 mg/kg CSH can be effective in improving FCR and the digestibility of organic matter in broilers.

• Journal of Korean Society of Environmental Engineers
• /
• v.22 no.12
• /
• pp.2205-2213
• /
• 2000

To investigate removal efficiency of dissolved matter by NF and RO, a pilot plant was operated for six months using groundwater treated by UF membrane. After the pilot plant operation, we performed autopsy test to identify characteristics of foulant attached on the membrane surface applying the used NF and RO in the pilot plant test. In autopsy test, we measured permeate flux and recovery rate of flux by chemical cleaning in each membrane. We also analyzed chemical cleaning disposal to examine component of foulant. Permeate flux of NF and RO1 showed rapid decline after 100 days of operation. Especially, reduction of specific flux in RO1 was more serious than in NF. Specific flux of RO2 with a low recovery rate resulted in gradual flux decline. Removal efficiencies of dissolved inorganic matters as a conductivity were 76.3%, 88.2% and 95.3% respectively for NF, RO1 and RO2, and RO2 presented the highest removal efficiency. And those of dissolved organic matters as TOC were about 80% for both NF and RO. The specific flux of membranes declined gradually from the feed water inlet to outlet of the membrane module and it showed that membrane fouling increased along the feed flow direction. Namely, concentration of pollutants became higher and volume of feed water was less as the feed flow approached to the outlet. It seemed that major foul ants were Ca consolidated into inorganic material and Si consolidated into organic material on the membrane surface. Fe was a great contribution to irreversible fouling. The SEM results indicated that the organic matter was attached to the first layer, closer to the membrane, and then inorganic matter with tetragonal shape layered over them. We could not observe biofouling because microorganism, which was cause of biofouling, was almost pretreated in UF membrane.

• Asian-Australasian Journal of Animal Sciences
• /
• v.2 no.4
• /
• pp.583-590
• /
• 1989

Increasing levels of ammonia-N in the rumen fluid used for in vitro incubation were achieved by supplementation of the ration of the donor cows with urea and by addition of urea either with or without glucose to the rumen fluid after collection. The ration of the donor animals consisted of wheat straw (80%) and maize silage (20%). During the second half of the experiment the basal ration was supplemented with a mineral mixture. Wheat straw, Guinea grass and two rice straw varieties were incubated with the various kinds of rumen fluid. Parameters studied were: solubility, apparent organic matter disappearance after 48 hours of incubation ($OMD_{48}$), rate of organic matter degradation from 0 to 24 hours of incubation ($k_1$) and from 24 to 95 hours ($k_2$). The concentration of ammonia-N in the rumen fluid at which 95% of the maximal $OMD_{48}$ and k1 were reached (88.2 and 100.0 mg/l) were independent of the feed. With regard to the $k_2$ the required ammonia-N concentration to reach 95% of the maximal $k_2$ differed per feed. Mineral supplementation increased the OMD48 and $k_1$, but not the solubility and $k_2$. Glucose addition in combination with urea had no beneficial effect compared to urea supplementation alone.

• Clean Technology
• /
• v.7 no.3
• /
• pp.195-202
• /
• 2001

In this study the trace of chlorinated organic compound in aqueous solution was separated by pervaporation process using crosslinked PDMS (polydimethylsiloxane) membrane. The flux of trichloroethylene(TCE) increased linearly with feed composition but the flux of water was slightly increased. The partial flux of TCE was greater than that of tetrachloroethylene(PCE). The partial flux of TCE was not changed with operating temperature, but increased rapidly with feed flow rates. High crosslinking density causes the reduction of solubility and diffusivity for target component. The reduction of flux and selectivity for TCE is due to the chain immobilization and reduction of diffusivity with crosslinking density.

• Korean Journal of Organic Agriculture
• /
• v.10 no.1
• /
• pp.35-47
• /
• 2002

In swine production, efficiency of utilization of nutrients is imperative. By embracing advances in processing techniques(i.e., fine grinding, pelleting, steam flaking, roasting, extrusion and expanding) nutrient utilization of feeds turfs have greatly improved. Grinding is by far the most commonly used process with reduction of particle size, Expander, like extruders, are high-temperature and pressure-short-term processor. The purpose of using an expander is to improve pellet quality. Also, expanding of dietary ingredients indicates improvements in growth performance and nutrient digestibility. Because feed cost are easily the greatest economic input into swine production, maximizing nutrient utilization is an area that will continue to receive much attention. Therefore, much attention will continue to be placed on feed processing techniques that will give consistent improvements in animal performance and nutrient digestibility.

• Journal of Power System Engineering
• /
• v.17 no.2
• /
• pp.87-94
• /
• 2013

Applicability of organic Rankine cycle for a passenger car with 3.5 L gasoline engine to convert low grade waste heat to useful shaft power has been numerically studied. Working fluid is R134a, and the Rankine cycle is composed of boiler for recovering engine cooling water heat, super heater for recovering exhaust gas heat, scroll expander for converting waste heat to shaft power, condenser for heat emission, internal heat exchanger, and feed pump. Assuming efficiencies of 90% for the heat exchangers, 75% for the scroll expander, and 80% for the feed pump, the Rankine cycle efficiency of 5.53% was calculated at the vehicle speed of 120 km/hr. Net expander shaft output after subtracting the power required to run the pump was 3.22 kW, which was equivalent to 12.1% improvement in fuel consumption. About the same level of improvement in the fuel consumption was obtained over the vehicle speed range of 60 km/hr~120 km/hr.

• Asian-Australasian Journal of Animal Sciences
• /
• v.13 no.8
• /
• pp.1094-1101
• /
• 2000

Thirty-six crossbred (70% Holstein Friesian) cows in mid-lactation were assigned to one of four treatments. The dietary treatments were concentrate based, containing 13.5, 27.0, 40.5 and 54.0% of cassava in concentrate replacing ground maize (16.0% CP). There were curvilinear responses to intake of organic matter, non-structural carbohydrate and metabolisable energy. Cassava and corn fed in a ratio of 50:50 maximised organic matter, metabolisable energy intake; milk yield, milk protein and lactose yield. Milk fat yield was not affected by levels of inclusion. Dietary treatment did not influence ruminal pH, ammonia and volatile fatty acid concentrations or plasma glucose. The low market price for cassava resulted in a lower concentrate feed cost. The optimal level of cassava in a dairy cow diet is suggested as being between 20.0 and 30.0% of cassava in dry matter intake when fed with rice straw.

• Ocean and Polar Research
• /
• v.45 no.3
• /
• pp.103-111
• /
• 2023

To evaluate the impact of effluents from land-based fish farms on the coastal ocean of Wando, Korea, we analyzed inorganic nutrients, particulate organic carbon (POC), dissolved organic carbon (DOC), and colored dissolved organic matter (CDOM) in the effluent and influent of land-based fish farms during the summer (July) of 2021. The average concentrations of nutrients (Dissolved inorganic nitrogen, phosphorus, and silicate; DIN, DIP, and DSi, respectively) in the effluents of this study area were 17±3.7 μM, 1.4±0.7 μM, and 14±1.6 μM, respectively. The average concentrations of POC and DOC were 37±22 μM and 81±13 μM, respectively, with POC accounting for about 30% for total organic carbon in effluents. The Reduced Dissolved Inorganic Nitrogen/Total Dissolved Inorganic Nitrogen ratio (0.7), potential short-period index, indicates that the discharge of nutrients excreted by the fish and unconsumed feed into coastal water results in such nutrients being deposited and accumulated in the sediment. Subsequently, this continuous accumulation triggers the release of ammonium ions during organic matter decomposition, and the ammonium-enriched waters that encroach on fish farms as influent seem to be due to the diffusion of high concentrations of ammonium from bottom sediment. Furthermore, we used fluorescence indices to examine the characteristics of organic matter sources, obtaining mean values of 1.54±0.19, 1.06±0.06, and 1.56±0.06 for the humification index, biological index, and fluorescence index, respectively, in the effluent. These results indicate that the organic matters had an autochthonous origin that resulted from microbial decomposition, and such organic matters were rapidly generated and removed by biological activity, likely supplied from the sediment. Our results suggest that the effluent from land-based fish farms could be a potential source of deoxygenation occurrence in coastal areas.