• Journal of Animal Science and Technology
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• v.48 no.4
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• pp.533-540
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• 2006

This experiment was conducted to determine crude protein requirements for maintenance (CPm) of growing Hanwoo steers. Eighteen Hanwoo steers (173.7kg) were allocated randomly to diets with three levels of crude protein in the concentrate by replacing ground corn with corn gluten meal: 0% (LCP), 7.2% (MCP) and 14.2% (HCP), respectively. Hanwoo steers in each treatment were fed diets containing rice straw (20%) and concentrates (80%). CP intake was 5.5, 7.8 and 10.7g/BW0.75 for LCP, MCP and HCP, respectively. Protein balance was －0.05, 2.36 and 4.07g/BW0.75 for LCP, MCP and HCP, respectively. Intercept of the regression equation between CP intake and retained CP indicated that CPm was 5.56g/BW0.75. The estimate of CPm adopted by Korean Feeding Standard (2002) was almost 20% higher than that adopted by Japanese Feeding Standard for Beef Cattle (2000); this would need to be verified with more feeding trial data set including protein requirements for growth.

• Applied Biological Chemistry
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• v.21 no.1
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• pp.63-67
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• 1978

The incorporation of activity in plasma lipid was determined after injection of $u-C^{14}-glucose$ to normal laying hen. The extraction of total lipid from plasma was carried out by the method of Floch et al. with some modifications. The counting of carbon-14 activity was conducted by a Beckman Liquid Scintillation System, The concentration of plasma lipid was estimated as much as 3,070mg per 100ml of plasma taken at 5 minutes after injection of tracer amount of $u-C^{14}-glucose$. The specific activity per gram of plasma lipid carbon atom per injected dose per kg body weight increased gradually following the time after injection until 120 minutes, whereas the glucose activity decreased logarithmically. The partial incorporation quotient of activity in plasma lipid from that of glucose was 0.73% until 120 minutes after the injection.

• Journal of Aquaculture
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• v.13 no.4
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• pp.331-338
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• 2000

To establish an alternate technology for all male seed production of Nile tilapia, Oreochromis niloticus at hatchery scale, the performance of progenies produced by crossing superfemale with sex reversed male was evaluated. Free crossings between 21 superfemales and 7 sex reversed males stocked in an aquarium for 60 days resulted in the production of 93.5 % male progenies, compared to 53.2 % males produced by an equal number of normal females and normal males. Spawning frequency was lower (19 times) in the experimental cross including superfemales than that (24 times) in the control including normal females. Seed production in the experimental aquarium was (3,085) significantly lower than that (3,797) of the control. Both in terms of seeds per female per day or seeds per g female per day, seed productivity did not significantly differ between these groups. The alternate technology involving crossing between superfemale and sex reversed male has proven to be an efficient alternate technology for mass production of all male seeds at the hatchery scale.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.31 no.3
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• pp.286-292
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• 1986

For the elucidation of saponin synthesis during ontogeny changes of ginsenosides and free sugars in seeds during stratification and seedlings in early growth stage were investigated with high performance liquid chrom-atography. Embryo plus endosperm at 40-day stratification showed 80% decrease of total saponin, disappear-ance of Rc, Rb$_2$ and Rb$_1$ and appearance of Rg$_3$ (probable) and 20-Glc-Rf (probable). Leaf ginsenoside F$_3$ was found not in fruit plup but seed and decreased during stratification. Both decomposition and synthesis of saponin seemed to occure during stratification. Ginsenosides in endosperm and embryo might be originated from fruit pulp by penetration. In seedling saponin appeared first in shoot and in root about one month later. Ginsenoside Rc, Rb$_2$, Rb$_1$ appeared in root at the last investigation (June 30) indicating normal saponin synthetic capacity of root. Saponin synthetic rate was twice in leaf than in root. Leaf ginsenoside F$_3$ was found in seedling root. Root saponin Rg$_3$ and 20-Glc-Rf were found in leaf and stem in seedling and decreased with growth suggesting that rate saponin is not such in certain growth stage. Total saponin content was negatively correlated with PT/PD in seeds and arial parts of seedling due to greater change of PD. than PT. Seed at 70days stratification showed high sucrose content. In seedling glucose was main sugar in stem all the while and sucrose in root at early stage while glucose, fructose and sucrose were found in leaf.

• Korean Journal of Soil Science and Fertilizer
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• v.30 no.2
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• pp.178-183
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• 1997

The effect of different relative humidity(RH) of atmosphere on the uptake of calcium by tomato plant was investigated through an experiment in the protected cultivation system. The RH regime was imposed by humidifiying by humidifier in one plot, and by mulching the ridge to cut down the evaporation of water to lower the RH, in another plot. During the course of plant growth, RH in the humidified plot, at noon, was about 70%, while in non-humidufied plot, RH was about 50%. The humidification also resulted in the lowering of temperature significantly(by about, $3.1^{\circ}C$). This higher RH of atmosphere under humidifying treatment, resulted in the increase in the water efflux rate of root significantly(greater by 0.24g/g dry root/h than that under mulching treatment). Relatively severe occurrence of blossom end rot(23%) was observed in the humidifying treatment, while no such symptom occurred in mulching plot. The efflux rates of Ca, K and Mg were found to be higher in the humidifying plot. It was also observed that the concentrations of Ca, Mg and K in the xylem solution was 2-4 times higher than that of gydroponic solution. This suggested that the occurrence of blossom end rot, under high RH of atmosphere, would not be due to the decrease in the uptake of Ca per se, by tomato plant, but due to anomalies in the distribution of it within the plant.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.28 no.3
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• pp.373-381
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• 1995

Oxygen consumption of marine fishes according to different water temperatures, fish population densities and body weights was measured in the respiratory chamber for the following six species: the olive flounder Paralichthys olivaceus, the tiger puffer Takifugu rubripes, the rockfish Sebastes schlegeli, the sea bass Lateolabrax Japonicus, the red seabream Pagrus major and the black seabream Acanthopagrus schlegeli. Also the lethal concentration of dissolved oxygen in them was determined. Oxygen consumption in each fish species increased as the water temperature increased. The relationship between the oxygen consumption rate $(Oc,\;ml/kg{\cdot}\;hr)$ and the water temperature (T,$^{\circ}C$) for each species appeared as the following equations demonstrate; olive flounder: Oc=34.0515T-339.5987 $(r^2=0.9730)$, tiger puffer: Oc=34.4941T-479.8732 $(r^2=0.9483),$ rockfish: Oc=44.7970T-634.2627 $(r^2=0.9718),$ sea bass: Oc=26.1488T-318.0633 $(r^2=0.9316),$ red seabream: Oc=61.1020T-722.8926 $(r^2= 0.9805),$ black seabream: Oc=75.1460T-947.9370 $(r^2=0.9392).$ The of gen consumption of fish with different population densities decreased as the number of fish increased. As the body weight of the olive flounder increased, the mass-specific oxygen consumption decreased. The relationship between oxygen consumption and body weight (W; g) was expressed as Oc=2532.0268W-0.6565 $(r^2=0.9229)$. The levels of lethal dissolved oxygen in the olive flounder, rockfish, tiger puffer and red seabream were 0.66, 0.79, 0.75 and 1.36 m1/1, respectively.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.32 no.3
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• pp.323-329
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• 1987

Five soybean varieties of two early maturing Karikei73 and SS 79168, and three late maturing Tohoku76, Baegunkong and Jangbaegkong were used and evaluated in the study. Of the varieties examined, Karikei73 was characterized by the delayed leaf senescence. The varieties were planted in the pots of 1/3500 a filled with volcanic ash soil at the experimental fields of the National Institute of Agrobiological Resources in Japan. Major agronomic characteristics including the activity of nitrogen fixation for root nodules during the grain filling period were measured. Measurements during the stages were followed by the stage of development descriptions for soybeans made by Fehr and Carviness (1977). The acetylene reducing activity (ARA) per dry weight of root nodule measured using acetylene reduction assays was the highest at R4-R4.5 with decreasing trends thereafter for the early matruing varieties, while it continuously increased up to R6 but decreased rapidly thereafter for the late maturing varieties. The dry weights of root nodules and all parts of the host plant at each stage checked were greater in the late maturing varieties being the same in ARA per pot.

• Applied Biological Chemistry
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• v.8
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• pp.21-28
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• 1967

Two experiments with 32 sheep were conducted to study the effects of feeding the same amount of diet per day at different meal frequencies on ration digestibility, energy utilization, rate of gain, body composition and efficiency of gain. The results obtained are as follows: (1) The ingestion by sheep of the same amount of feed per day in 8 meals, 1 meal plus 7 ruminal inflations-deflations, and in 1 meal caused no different effect in the digestibility of the nutrients and energy, or the ME value of the diet. (2) Heat production per unit of metabolic size per unit of dietary intake was markedly lower for sheep ingesting 8 meals or administered 1 meal plus 7 ruminal inflations-deflations per day than for sheep fed 1 meal per day. (3) Body weight gain was significantly greater by sheep fed 8 meals per day or 1 meal plus 7 ruminal inflations-deflations than by those fed 1 meal per day. However, the gain in DM and energy of wool was not affected by frequency o( meals. (4) Sheep ingesting 8 meals or administered 1 meal plus 7 ruminal inflations-deflations per day gained body protein, fat and energy at a more rapid and efficient rate than sheep fed 1 meal per day. (5) Sheep fed 8 meals per day gained greater proportion of fat, protein and ash in the gained portion of the bodies than did 1 meal fed sheep. (6) An attempt was made to establish the possible explanations by which the frequency of ingesting meals exerts its effects.

• Korean Journal of Weed Science
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• v.3 no.2
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• pp.151-155
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• 1983

Photosynthetic activity of two rice varieties "Suweon 318, Nagdongbyeo" and two species of grass weeds, two species of sedge weeds, and four species of broadleaf weeds was measured at 5, 10, 20, 30, 40, 50 Klux light intensity. Relative photosynthetic activity of weed species was high in the decreasing order in Cyperus serotinus, Echinochloa grusgalli var caudata, Bidens tripartita, Monochoria vaginalis, and Ludwigia prostrata, while respiration rate was high in Bidens tripartite, Monochoria vaginalis and Cyperus serotinus. Light saturation point of Monochoria vaginalis and Sagittaria pygrnaea may be considered as at 30 klux and photosynthetic rate of other weed species increased with increasing light intensity. Photosynthetic activity of weed species was generally two times higher than rice at the light intensity of 50 klux and increased more than rice as light intensity increased. Photosynthetic activity per leaf dry weight and specific leaf area was higher in broadleaf weeds than in grass and sedge weed species.

• Korean Journal of Organic Agriculture
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• v.20 no.3
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• pp.369-383
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• 2012

This experiment was carried out to investigate the optimal stocking rate of earthworm populations grown under different stocking rates. The stocking rate in terms of ratio of biomass of earthworms to biomass of feeds(organic resources) is an important factors for biomass productivity of earthworms and vermicast production. The different stocking rates were 1:16(S-1), 1:32(S-2), 1:48(S-3) and 1:64(S-4), as the ratios of biomass of earthworm to biomass of organic dairy cow manure, respectively. The stocking rate of 1:32(S-2) and 1:46(S-3) were obtained a higher values on increasing rates and conversion efficiency of organic matter to earthworm biomass than other stocking rates. Thus, a stocking rates of 1:32 and 1:46 estimated an optimal stocking rates for maximum biomass productivity of earthworms. A stocking rate of 1:16(S-1) showed a significantly highest values of vermicast production and ratios of vermicasts during the rearing periods.($$P{\leq_-}0.05$$) A stocking rate of 1:48(S-3) showed a highest values of the number of cocoons and vermicasts production per earthworm biomass among the treatment ($$P{\leq_-}0.05$$) The contents of nitrogen, available phosphorus, cation exchange capacity and exchangeable cations of vermicasts tended to increase with stocking rate and rearing progressed. Vermicasts have a great deal of potential for crop production and protection in sustainable organic cropping systems.