• 한국가금학회지
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• 제27권3호
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• pp.169-179
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• 2000

An experiment was conducted to measure the effect of crude phytase supplementation on the growing performance, blood concentrations of some minerals and tibia characteristics of broiler chickens. Day-old 240 male broiler chickens (Avian) were randomly allotted to four treatments. There were six replicates per treatment, and ten chicks per replicate. Treatments consisted of two levels of crude phytase (0 and 600U/kg) made from Aspergillus ficuum and two levels of non-phytate P (0.45 and 0.35% NPP for the starter period, and 0.35 and 0.25% NPP for the grower period), making the experiment 2$\times$2 factorial. The starter period was from hatch to 21 d of age, and grower period was from 22 to 35 d of age. Feed intake and weight gain of chicks fed diet containing phytase were higher(P〈0.05) than those of chicks fed diets without phytase, however, no differences was found in feed/gain. mortality, and nutrient availabilities regarding the phytase supplementation. Chickens fed diets with low NPP and phytase excreted lower P than did birds fed diets containing normal NPP without phytase. The level of NPP and phytase did not affect N excretion. The Ca availability was increased by feeding low NPP diet. Dietary phytase increased the availabilities of P and Mg, but decreased those of Fe and Zn. There was interactions between dietary NPP level and phytase addition on mineral availability. Tibia was lighter and shorter in low NPP groups, and heavier in phytase treated groups. The tibial contents of Ca, P and Mg decreased in low NPP treated groups, but increased in phytase treated groups. The ash content of tibia of chickens fed diet with phytase was higher than that of birds fed diets without phytase. These data suggest that the crude phytase supplementation to broiler diets containing low NPP level improves growth performance and mineral availability and, reduces fecal P excretion.

• 한국환경농학회지
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• 제26권4호
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• pp.286-296
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• 2007

To increase phosphate (P) availability in soils, the efficiency of silicate (Si) in reducing P adsorption was investigated by competitive adsorption tests under changing conditions of pH, ion concentrations, and order of anion addition along with single adsorption properties of each ion at $20^{\circ}C$. In the single ion adsorption study, P and Si ions showed the opposite reaction patterns: phosphate adsorption decreased with increasing pH and attained adsorption maximum however, silicate adsorption increased with increasing pH without attaining adsorption maximum. Phosphorus and Si adsorption were influenced by pH in the range of 5.0 - 9.0 and the type and amount of P and Si concentration. Silicate added to soil before P or in a mixture with P significantly reduced P adsorption above pH 7.0; however, there was no significant Si-induced decreased in P adsorption at pH 5.0 when anions were added as mixture. The efficiency of Si in reducing P adsorption increased with increasing Si concentration and pH. The effect of P on Si adsorption was relatively small at pH 5.0 and no effect of P on silicate adsorption was observed at pH 9.0. The presence of Si strongly depressed P adsorption when Si was added before P compared to P and Si added as a mixture. These results suggest that application of Si may decrease P adsorption and increase the availability of P in soils. Furthermore, a Si source would be better to add before P application to enhance the availability of P in soils.

• 한국양식학회지
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• 제7권3호
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• pp.165-175
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• 1994

육상에서 틸라피아를 양식할 때 문제가 되는 질소 및 인의 부하량을 측정하기 위하여, 시판되는 상품 사료로 치어와 미성어를 사육하여 사료 중 영양 성분의 소화율과 분의 배설량 등을 통해 환경수계에 미치는 오염 부하량을 추정하였다. 시판되는 틸라피아 사료의 단백질 함량은 평균 $33.8\%$ (질소 함량 $5.4\%$)였고, 인 함량은 평균 $1.4\%$였으며, 사료 공급후 24 시간내에 총 분 배설량의 $60\%$가 배설되었다. 틸라피아 치어 (평균 어체중 65.2g) 및 미성어 (평균 어체중 389g)좌 단백질 소화율 및 인의 소화율은 거의 차이가 없었으나, 지방의 소화율은 치어가 높았다. 질소 수지는 치어와 미성어의 경우, 공급한 질소의 $7.1\%$와 $9.9\%$를 분으로 배설하였고 뇨와 아가미를 통하여는 각각 $55.5\%$와 $62.3\%$를 배설하여, 어체에는 각각 $37.4\%$와 $27.8\%$를 축적하였다. 따라서 성장함에 따라 질소의 축적량은 줄면서 배설량은 늘어나는 것으로 나타났다. 한편, 치어 1 톤 생산당 질소 및 인 부하량은 평균 49.5 kg과 6.3 kg 이였고 미성어의 경우 61.3kg과 13.4kg으로 어체 크기가 클수록 오염 부하량도 많아졌다.

• Journal of Microbiology and Biotechnology
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• 제27권6호
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• pp.1150-1156
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• 2017

Understanding phosphorus metabolism in photosynthetic organisms is important as it is closely associated with enhanced crop productivity and pollution management for natural ecosystems (e.g., algal blooming). Accordingly, we exploited highly time-resolved metabolic responses to different levels of phosphate deprivation in Chlamydomonas reinhardtii, a photosynthetic model organism. We conducted non-targeted primary metabolite profiling using gas-chromatography time-of-flight mass spectrometric analysis. Primarily, we systematically identified main contributors to degree-wise responses corresponding to the levels of phosphate deprivation. Additionally, we systematically characterized the metabolite sets specific to different phosphate conditions and their interactions with culture time. Among them were various types of fatty acids that were most dynamically modulated by the phosphate availability and culture time in addition to phosphorylated compounds.

• Journal of Plant Biology
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• 제11권3호
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• pp.1-7
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• 1968

Organic matter in rice-paddy soils exercises two antagonistic effects on the rice plant under water-logged conditions in growing season in the course of its decomposition: It liberates mineral nutrients and promotes soil fertility. On the other hand, however, it demands oxygen for its decay and therefore competes with rice roots for this element, when applied in large quantity of fresh status. For the practical end of rice culture, it is most desirable that these two effects should not contend with each other. To determine the proper content of organic materials to be applied, the influences of varied amounts of a homogeneous mixture of dried green manure, ranging from 0 to 20g/pot (1/20,000 tanbo), upon hte growth of rice was investigated in a sand culture. Labeled phosphorus fertilizer was also used in the form of KH232PO4 to evaluate the availability of this nutrient in the soil. Under the present experimental conditions, green mature seems to have influenced little on the growth of rice, except on number of grains produced and grains/straw ratio. Moreover, no sympton of growth inhibition is obsrvable even by the largest amount of its application. The available phosphorus, as estimated by A-value, appears to have increased, as the amount of organic materials applied increases. In view of the fact that pure sand instead of a paddy soil is used in this culture, the present results would not be directly applicable to practical rice farming. Besides, the estimated A-value is in need of further study, since it varies according to method of application, as suggested by Nishigki et. al. (1958).

• Journal of Plant Biology
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• 제10권1_2호
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• pp.36-40
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• 1967

1. The effect of the pH value on P32 absorption of leaves of three forest trees under the water culture is investigated. 2. The degree of the P32 absorption to the pH value is quite different in each forest tree. 3. The phosphorus contents are proved higher in the leaves of Quercus accutissima(the saw shaped oak) than in the leaves of Pinus densiflora(the red pine) and Lespedeza bicolar (bush clover). 4. Larger contents of phosphorus are found in acidity plots than in alkalinity. The leaves of treated plot of the pH 4 (red pine), of the pH 5.0 (bush clover), and of the pH 5.0-6.5 (saw shaped oak) have a higher nutrient capital as indicated by P32 compared with that of the other pH values. 5. It is also noticed that P32 absorption capacity is decreased with the higher pH values. 6. The content of P of leaves shows the lowest value in the plot of the pH 6.5 (pine), of the pH 7.5(bush clover), and of the pH 9.0(saw shaped oak). It is also noticed that the red pine is to do very well in acid cultivation and then follow bush clover and saw shaped oak in the order.

• 한국육종학회지
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• 제42권5호
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• pp.455-462
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• 2010

Purple acid phosphatase is important for phosphorus remobilization in plants, but its role in plant adaptation to low phosphorus availability is not known. The cDNA encoding O. sativa purple acid phosphatase (OsPAP1) has 1008 bp with an open reading frame of 335 amino acid residues. The amino acid sequence of OsPAP1 cDNA shows of 50-51% identity with other plant purple acid phosphatases. OsPAP1 was expressed in rice plants and in cell cultures in the absence of phosphate ($P_i$). The expression was organ-specific with the strongest expression in $P_i$-deprived roots. Functional expression of the OsPAP1 gene in the transgenic Arabidopsis line was confirmed by northern and western blot analysis. OsPAP1 overexpression lines had higher phosphatase activity than wild-type. Overexpression of OsPAP1 in Arabidopsis plants resulted in increased Pi accumulation under Pi sufficient condition. These results show that the OsPAP1 gene represents more efficient $P_i$ uptake and can be used to develop new transgenic dicotyledonous plants.

• 농업과학연구
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• 제50권4호
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• pp.653-661
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• 2023

Phytase enhances phosphorus availability in pig diets by breaking down phytic acid, which is challenging for animals to digest. This study aimed to assess the impact of dietary phytase supplementation on the growth performance, nutrient digestibility, and fecal score of growing pigs. Sixty-four growing pigs ([Yorkshire × Landrace] × Duroc, average body weight 21.20 ± 0.18 kg) were randomly assigned to one of two treatment groups. The dietary treatments were CON, basal diet, and PHY, basal diet + 0.0025% phytase. Results indicated a tendency for increased average daily gain in the phytase-supplemented diet group (p < 0.10) compared to the control diet group. The average daily feed intake and feed conversion ratio were not affected by the addition of 0.0025% phytase. Furthermore, dry matter digestibility, nitrogen content, and digestible energy were not influenced (p > 0.05) by phytase supplementation. Fecal score remained similar (p > 0.05) in growing pigs fed phytase-supplemented and control diets. These findings suggest that supplementing the diet of growing pigs with 0.0025% phytase may lead to improved average daily gain without adverse effects on nutrient digestibility and fecal score. This implies the potential to enhance growth performance without compromising overall health or digestion in pigs. Further investigations into the optimal levels of phytase supplementation for growing pigs are recommended.

• Asian-Australasian Journal of Animal Sciences
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• 제21권4호
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• pp.603-615
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• 2008

Dietary fiber is an inevitable component in pig diets. In non-ruminants, it may influence many physiological processes in the gastrointestinal tract (GIT) such as transit time as well as nutrient digestion and absorption. Moreover, dietary fiber is also the main substrate of intestinal bacteria. The bacterial community structure is largely susceptible to changes in the fiber content of a pig's diet. Indeed, bacterial composition in the lower GIT will adapt to the supply of high levels of dietary fiber by increased growth of bacteria with cellulolytic, pectinolytic and hemicellulolytic activities such as Ruminococcus spp., Bacteroides spp. and Clostridium spp. Furthermore, there is growing evidence for growth promotion of beneficial bacteria, such as lactobacilli and bifidobacteria, by certain types of dietary fiber in the small intestine of pigs. Studies in rats have shown that both phosphorus (P) and calcium (Ca) play an important role in the fermentative activity and growth of the intestinal microbiota. This can be attributed to the significance of P for the bacterial cell metabolism and to the buffering functions of Ca-phosphate in intestinal digesta. Moreover, under P deficient conditions, ruminal NDF degradation as well as VFA and bacterial ATP production are reduced. Similar studies in pigs are scarce but there is some evidence that dietary fiber may influence the ileal and fecal P digestibility as well as P disappearance in the large intestine, probably due to microbial P requirement for fermentation. On the other hand, fermentation of dietary fiber may improve the availability of minerals such as P and Ca which can be subsequently absorbed and/or utilized by the microbiota of the pig's large intestine.

• Asian-Australasian Journal of Animal Sciences
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• 제14권7호
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• pp.979-985
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• 2001

Two experiments on commercial broiler chickens (3-37 d) and WL layers (252-364 d) were conducted to study the relative bioavailability of phosphorus (P) from different P supplements in comparison to tricalcium phosphate (TCP), at constant dietary calcium (Ca):P ratio. The P sources tested were dicalcium phosphate (DCP), steam sterilized bone meal (SSBM), commercial mineral mixture (CMM), phosphoric acid (PA) and a combination of CMM + PA. Fluorine (F) content in CMM and SSBM was 13.12 and 0.14 g/kg, respectively. In commercial broiler diets, DCP, SSBM or PA could be used as supplemental P sources without affecting (p<0.05) weight gain, feed intake, tibia ash and, P and Ca contents in tibia ash when compared to TCP. Severity of leg abnormality and deposition of F in bone were higher (p<0.05) in group fed CMM. P retention and serum inorganic P content was significantly reduced (p<0.05) in CMM fed birds compared to those fed TCP, SSBM, PA or CMM+PA. Among other P sources (TCP, SSBM, PA and CMM+PA) the serum inorganic P levels did not vary significantly (p<0.05). The P retention also significantly reduced in CMM fed groups compared to those fed DCP or PA. The P retention significantly increased from 0.183 to 0.216 units by supplementation of PA to CMM diet. In layers, egg production was not affected by replacing TCP with DCP, SSBM, PA or CMM+PA, but significantly (p<0.05) reduced with CMM. Feed (kg)/kg egg mass, egg weight, shell quality (shell weight and shell thickness) and serum Ca levels were not influenced by dietary variation in P source. The poor performance of both broilers and layers fed on CMM based diets could be attributed to the presence of hlgher levels of F (647.8 and 630.1 mg/kg, respectively) and low P utilization. Based on growth, bone mineralization and P retention it is concluded that DCP, SSBM or PA can be used as alternatives to TCP in broiler diets. In WL layer diets, in addition to above P sources, CMM can also be used as supplemental P source by replacing one half of P from CMM with PA without affecting egg production and shell quality.