• Journal of Microbiology and Biotechnology
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• 제24권8호
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• pp.1034-1043
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• 2014

This study determined the effect of light intensity and photoperiod on the dry cell weight and total amount of carotenoids in four isolates of purple non-sulfur bacteria obtained from shaded and exposed microhabitats of a mangrove ecosystem in Kota Kinabalu, Sabah, Malaysia. The initial isolation of the bacteria was carried out using synthetic 112 medium under anaerobic conditions (2.5 klx) at $30{\pm}2^{\circ}C$. On the basis of colony appearance, cell morphology, gram staining, motility test, and 16S rRNA gene sequencing analyses, all four bacteria were identified as Afifella marina. One of the bacterial isolates, designated as Af. marina strain ME, which was extracted from an exposed mud habitat within the mangrove ecosystem, showed the highest yield in dry cell weight ($4.32{\pm}0.03g/l$) as well as total carotenoids ($0.783{\pm}0.002mg/g$ dry cell weight). These values were significantly higher than those for dry cell weight ($3.77{\pm}0.02g/l$) and total carotenoid content ($0.706{\pm}0.008mg/g$) produced by the isolates from shaded habitats. Further analysis of the effect of 10 levels of light intensity on the growth characteristics of Af. marina strain ME showed that the optimum production of dry cell weight and total carotenoids was achieved at different light intensities and incubation periods. The bacterium produced the highest dry cell weight of 4.98 g/l at 3 klx in 72 h incubation, but the carotenoid production of 0.783 mg/g was achieved at 2.5 klx in 48 h incubation. Subsequent analysis of the effect of photoperiod on the production of dry cell weight and total carotenoids at optimum light intensities (3 and 2.5 klx, respectively) revealed that 18 and 24 h were the optimum photoperiods for the production of dry cell weight and total carotenoids, respectively. The unique growth characteristics of the Af. marina strain ME can be exploited for biotechnology applications.

• Journal of Animal Science and Technology
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• 제58권10호
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• pp.36.1-36.5
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• 2016

Background: Liquid feeding system has been introduced to domestic swine farms, but negative cognition about liquid feeding system has been remained for feed waste decay related with poor management and microbial contamination. For these reasons, this study was conducted to evaluate the effects of feeding method in lactating sows. Methods: A total of 30 mixed-parity (average 4.13) lactating sows (Yorkshire ${\times}$ Landrace) with an initial BW of $218.8{\pm}19.5kg$ was used in a 3 week trial. Sows were allotted to 1 of 2 treatments in a completely randomized design by their body weight, backfat thickness, parity and alive litter weight. One of treatments was dry feeding and the other was liquid feeding (water to feed ratio, 1:1). Experimental diets contained 3265 kcal ME/kg, 12.6 % CP, 5.76 % EE, 1.09 % total lysine, 0.25 % total methionine, as fed basis. Results: Dry feeding treatment had high body weight loss rather than liquid feeding treatment (P = 0.04). Dry feeding treatment had tendency to increase litter weight at 21d of lactation (P = 0.06) and litter weight gain (P = 0.04) during lactation period (0-3 week). Sows fed dry feeding method made milk containing high content of casein and total solid rather than sows fed liquid feeding method (P = 0.04). In addition, dry feeding treatment had tendency to higher content of milk fat, protein and solid not fat on 21d of lactation (P = 0.07). Sows fed dry feeding type also showed higher milk energy content in milk of 21d lactation (P = 0.05). Furthermore, liquid feeding treatment showed high occurrence in feed waste during lactation period (P <0.01). Conclusion: Dry feeding method was more suitable feeding method to lactating sows under high temperature environment like lactating barn.

• 한국자원식물학회지
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• 제14권2호
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• pp.89-93
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• 2001

Source와 Sink의 차이가 있는 고구마 품종간 이면 접목을 통하여 수량에 미치는 source와 sink의 상대적 기여도를 구명함으로서, 고구마의 품종육성 및 재배법개선에 필요한 기초자료를 얻고자 율미, 신율미, 건미, 홍미 및 선미의 5품종을 공시하여 저장능력과 생산능력을 분석 하였다. 1.경엽중과 괴근중에 대한 일반접목효과(GGE), 특정접목효과(SGE) 및 정역접 목 효과(RCE)가 모두 고도로 유의한 차이가 있었다. 2 총 건물중은 접목에 의하여 감소되었으며, 접목조합에 따라서 차이가 있었다. 3. 생산능력은 접수 그리고 저장능력은 대목의 영향을 많이 받았다. 4.신율미는 잠재생산능력과 잠재저장능력이 높아, 총 건물중이 많았으며, 홍미와 율미는 잠재생산능력이 낮아 총 건물중이 적었다.

• Asian-Australasian Journal of Animal Sciences
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• 제16권2호
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• pp.172-175
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• 2003

The regression equations of dry weight of planktonic biomass upon physico-chemical characteristics of fifteen ponds in three replicates under the influence of artificial feed, broiler manure, buffalo manure, N:P:K (25:25:0) and a control pond was obtained after one year of experimental period by using stepwise regression method. Water samples from each of the ponds were analyzed daily. However, the average values were calculated on the basis of 15 day intervals designated as fortnight. In artificial feed supplemented pond the regression of average nitrates on dry weight of planktonic biomass accounted for 71.7% of the variation in biomass. In broiler manure fertilization pond the regression of total nitrogen on dry weight of planktonic biomass held it responsible for more than 74.6% of variation in biomass. In buffalo's manure fertilized pond more than 82% of the variations in biomass were due to total nitrogen. In case of N:P:K (25:25:0) treated pond 66% of the variation in the dry weight of planktonic biomass was due to average nitrates. The control pond showed the dependence of biomass on light penetration. This equation explained more than 62 percent of variation in biomass. Other variables also showed some contribution towards variation in biomass under all the treatments in these regression studies.

• Journal of Plant Biology
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• 제14권3호
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• pp.21-28
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• 1971

Dry matter production, leaf area growth and total nitrogen changes were studied in Glycine max. soybean communities, which were grown in sandy loam soils controlled to provide various moisture levels, i.e., 5-7%(level 1), 8-10%(level 2), 11-13%(level 3), 14-15%(lev디 4), 17-20%(level 5) and 22-24%(level 6). A summary of the results is shown. The maximum dry matter production of leaves, stems and nodules and the maximum leaf area per unit area were at level 5, but the maximum of root dry matter production was at level 4. Total nitrogen content of the soybean plant decreased with growth, but each level of soil moisture content also showed a little difference. Water content of the plant decreased with plant age and soil water deficiency, especially in roots and nodules. Nodule formation increased in proportion to soil moisture content. total nitrogen content of the soil on which the soybeans grew, increased from 0.23% before sowing to 0.30% at 100 days after sowing. It seems that soil water content acts as a linear factor in the elongation or dry weight increase of shoots and roots until increasing to level 5. Considering the pattern of plant growth through analysis of the shoot and root dry weight ratio, or the photosynthetic organ and non-photosynthetic organ dry weight ratio, the asymptote of plant growth at a high soil water content exceeded that at a low soil water content.

• 한국초지조사료학회지
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• 제18권4호
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• pp.291-302
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• 1998

식물생장 조절제 Uniconazole-P의 처리가 초지조건에서 목초의 생육억제와 종자생산에 미치는 영향을 검토하였다. 초종은 화본과 목초 2초종(orchardgrass와 timothy)과 두과목초 2초종(red clover와 alfalfa)을 공시하였고, Uniconazole-P의 처리농도는 대조구, 20ppm구, 40ppm구의 3처리로 하여, 화본과 목초는 유수분화기에, 두과목초는 개화시기(開花始期)에서 엽면산포하였다. 본 실험에서 얻어진 결과를 요약하면 다음과 같다. 1. Uniconazole-P의 처리효과는 처리농도, 초종 및 생육단계에 따라서 차이가 인정되었다. 2. Uniconazole-P의 처리는 출수초기의 화본과 목초에서 초장과 간장이 단축되었고, 수중과 엽록소 함량을 증가시켰다. 3. Uniconazole-P의 처리는 종자 결실기의 orchardgrass에서 수수, 1경중, 수중, 1수중 및 종자중을 증가시켰고, timothy에서는 초장의 단축과 수수, 1수중, 수중, 종자중 및 수확지수를 증가시켰다. 4. Uniconazole-P의 처리는 개화초기의 red clover와 alfalfa 2초종 모두 초장과 총절간장을 단축시켰지만, 총분지장과 엽록소 함량을 증가시켰다. 특히 red clover에서는 화수와 화중의 증가가 현저하였다. 5. Uniconazole-P의 처리는 종자 결실기의 red clover에서 초장을 단축시켰고, 화중과 종자중을 증가시켰으며, alfalfa에서는 초장을 단축시키고 화중, 종자중 및 수확지수를 증가시켰다. 6. Uniconazole-P의 처리에 의한 화본과 목초의 종자 생산과정은 1) 출수초기에서 초장과 간장의 단축, 2) 출수초기와 종자 결실기에서 수수와 l수중의 증가, 3) 종자 결실기에서 단위면적당 수중과 종자중의 증가 및 수확지수의 증가로 설명할 수 있다. 7. Uniconazole-P의 처리에 의한 두과목초의 종자 생산과정은 1) 개화초기에서 초장과 총절간장의 단축과 분지수와 총분지장의 증가, 2) 개화초기와 종자 결실기에서 화수와 화중의 증가, 3) 종자 결실 기에서 종자중과 수확지수의 증가로 설명할 수 있다.

• The Korean Journal of Ecology
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• 제20권5호
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• pp.367-373
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• 1997

The effects of salinity on the growth and production of rice were studied at Seosan reclaimed land from July to October, 1995. The plant height, the number of living aleaves, dead leaves and total leaves, the number of the grains and the dry weight of the grains per individual, and the dry weight of above the ground in $25cm{\times}25cm$ quadrat were investigated on 5 plots whers were different salinity. The plant height, the number of living leaves and total leaves and the number of grains and the dry weight of grains per individual, and the dry weight of above the ground decreased as the salinity of water increase and the number of dead leaves of rice increased as the salinity of water decrease. The effect of salinity on the reproductive production is severer than the vegetative production. Because of the salinity, the growth and the production of the rice at Seosan reclaimed land are worse than the normal rice field.

• Asian-Australasian Journal of Animal Sciences
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• 제12권6호
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• pp.854-861
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• 1999

Seventeen pregnant ewes (8 superovulated and 9 non-superovulated) were used to study correlations of maternal serum progesterone concentrations with uterine and fatal weights at weeks 7 and 15 of pregnancy. Statistical analyses indicated that uterine growth during the first 7 weeks of pregnancy highly associated with maternal serum progesterone concentration (r=0.87 and 0.85, with wet and dry uterine weights, respectively). Ewes with higher maternal serum progesterone concentrations had higher total and average fetal weights at week 7 of pregnancy (r=0.89 and 0.86, respectively). At week 7 of pregnancy, wet and dry uterine weights highly correlated (p<0.01) with total and average fatal weights (r=0.99 and 0.80, 0.98 and 0.75, respectively). Maternal serum progesterone concentrations, however, did not correlate (p>0.05) with wet and dry uterine weights (r=0.36 and 0.47, respectively) and with total and average fetal weights (r=0.20 and 0.58, respectively) at week 15 of pregnancy. However, wet and dry uterine weights had high correlation with total fetal weight (r=0.97 and 0.95, respectively), without significant correlation with average fetal weight. It was concluded that during the embryonic stage of pregnancy, the levels of maternal progesterone were highly correlated with uterine and fetal growths, while during the fetal stage pregnancy, the correlation became less evident.

• Fisheries and Aquatic Sciences
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• 제27권6호
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• pp.356-365
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• 2024

The study was conducted in the Terie River between January and April 2022. The objectives of the study were to assess the fish species composition, determine the length-weight relationship and condition factor and assess the water quality of the river using international water quality guideline for aquatic life. Gillnets with different mesh sizes, 4, 6, 8 and 10 cm were used to collect fish specimens in both dry and wet seasons. Immediately after capture, the total length (TL) and total weight (TW) of each individual were measured in centimeters and grams, respectively, and their relationship was determined using the power function. The physicochemical water quality parameters were analyzed using standard procedures and wagtech portable water quality Kits and Secchi Disk apparatus. A total of 667 fish specimens were collected from the Terie River, 410 and 257 in dry and wet seasons respectively. A total of six fish species, Oreochromis niloticus, Labeobarbus intermedius, Labeobarbus nedgia, Labeobarbus beso, Clarias gariepinus, and Ramius loti were recorded. For length-weight relationship and condition factor analysis, more abundant fish species (O. niloticus and L. intermedius) which were found in both seasons were selected. The length and weight relationship of L. intermedius were TW = 0.0073TL^3.04 in dry and TW = 0.0337TL^2.59 in we season indicated isometric and negative allometric growth respectively. While O. niloticus showed negative allometric growth, TW = 0.096TL^2.44 and TW = 0.0335 TL^2.76 in dry and wet seasons, respectively. The mean Fulton condition factor (FCF) of L. intermidus were 0.85 ± 0.03 and 0.94 ± 0.25 in dry and wet seasons, respectively. The FCF of O. niloticus was 1.70 ± 0.13 and 1.73 ± 0.12 in dry and wet seasons respectively. Except for ammonia, the physicochemical water quality parameters were with the permissible limit for aquatic life and are suitable for fishes Terie River. The river has commercially important fish specimens that could be used for food security and livelihood improvement. However, there is very limited fishing activity in the river due to less awareness on the value of fishes. Therefore, sustainable fishery development should be done in the river.

• The Korean Journal of Ecology
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• 제23권2호
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• pp.181-185
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• 2000

This study was carried out to see whether Gastrophysa viridula (Degeer) (Coleoptera : Chrysomelidae) could be used as a biological control agent for Rumex obtusifolius L., with human manipulation of the beetle population. The study was consisted of three experimental sets : Wet-Dry experiment (the wet weight Vs dry weight relationship of Rumex obtusifolius L.), Greenhouse feeding experiment, and Field experiment. There was a significant correlation between the total wet and dry weight of Rumex obtusifolius as follows : Total dry weight : -0.23542+ (0.17514${\times}$Total wet weight) ($R^2$=0.9317, p=0.047, T=16.927 (dF=21)). In the Greenhouse feeding experiment, the result was very promising. The relationship between the density unit of the beetles and the growth of the plant is given below (20 day) : Plant growth =105.8+(-34.4${\times}$Density unit) ($R^2$=0.76, p=0.13). A repeated introduction of the beetle population into the field vegetation of R. obtusifolius from April to October is suggested to see the beetle's grazing ability on the plant. This study shows that the potential grazing power of the beetle on Rumex obtusifolius was enough to defoliate the plants, but it was able to recover from its root reserves. The practical question remains as to whether repeated additions (by man) of the beetles to Rumex obtusifolius could eliminate them.