• Asian-Australasian Journal of Animal Sciences
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• 제33권7호
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• pp.1103-1112
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• 2020

Objective: To measure whether a microbial additive could effectively improve the fermentation quality of delayed-sealing (DS) silage, we studied the effects of inoculants of lactic acid bacteria (LAB) and cellulase enzyme on microbial populations, ensiling characteristics, and spoilage loss of DS silage of Napier grass in Africa. Methods: Quick-sealing (QS) and DS silages were prepared with and without LAB (Lactobacillus plantarum) inoculant, cellulase enzymes, and their combination. The QS material was directly chopped and packed into a bunker silo. The DS material was packed into the silo with a delay of 24 h from harvest. Results: In the QS silage, LAB was dominant in the microbial population and produced large amounts of lactic acid. When the silage was treated with LAB and cellulase, the fermentation quality was improved. In the DS silage, aerobic bacteria and yeasts were the dominant microbes and all the silages were of poor quality. The yeast and mold counts in the DS silage were high, and they increased rapidly during aerobic exposure. As a result, the DS silages spoiled faster than the QS silages upon aerobic exposure. Conclusion: DS results in poor silage fermentation and aerobic deterioration. The microbial additive improved QS silage fermentation but was not effective for DS silage.

• Asian-Australasian Journal of Animal Sciences
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• 제17권1호
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• pp.53-62
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• 2004

The aim of this study was to predict the energy value and dynamic degradation of roughage in Taiwan using the $Daisy^{(R)}$. in vitro fermentation method to provide information on one of the very important nutrients for ration formulation. The second objective was to study the effects of Aspergillus oryzae (AFE) inclusion on nutrient utilization. Three ruminal fistulated dry dairy cows were used for rumen fluid and fifteen conventional forages used in dairy cattle were collected around this island. The degradability of these feedstuffs with and without AFE ($Amaferm^{(R)}$.) treatment was measured using the $Daisy^{(R)}$. in vitro method. The roughage energy values, including TDN and NEL, were calculated according to Robinson (2000). Results from the 30 h in vitro neutral detergent fiber (NDF) degradability and predicted energy evaluations showed that alfalfa (among the forages) contained the highest degradability and energy values, Bermuda straw having the lowest. Peanut vines and corn silage contained higher energy values and the lowest value found in Pangola and Napier grasses among the locally produced forages. Pangola and Napier grasses had lower values than most imported forages except Bermuda straw. Among the by-products, wheat middling contained the highest NDF degradability, while rice bran contained the richest energy value due to its high oil content. From the dynamic dry matter (DM), organic matter (OM), acid detergent fiber (ADF) and neutral detergent fiber (NDF) degradation, corn silage contained the highest effective degradation among the local forages; wheat middling (among the by-products) degraded the fastest in DM, OM, ADF and NDF and showed the highest effective degradability. AFE inclusion was inconsistent among the forages. Alfalfa hay showed significantly increased 30 h NDF degradability and energy values, Pangola hay, Napier grass and brewer's grains showed decreased degradability and energy values. AFE inclusion increased the DM, OM and NDF degradation rate in most forage, but only increased the DM degradation rate in sorghum distiller's grains, the OM degradation rate in bean curd pomace and the NDF and ADF degradation rates in soy pomace (among the by-products).

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 1993년도 Proceedings of International Conference for Agricultural Machinery and Process Engineering
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• pp.686-695
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• 1993

A flywheel-type, inclined axis chopper for small-area rice and livestock farmers, has been developed at IRRI Agricultural Engineering, The prototype is belt-driven by a 2.6kW engine and uses four angled blades rotating below a fixed counteredge. Manual feeding is facilitated by a convenient spout presenting the crop to the inclined blade housing and also suction created by the rotating blades . The distance between the rotating blades and the bottom of the housing determines the length of chops, set here for 25 cm. The unit would cost $200 without the engine. Tests with napier grass, corn stalks , and rice straw showed satisfactory performance within the acceptable clearance, speed and moisture content ranges of the material presented. Highest capacities were 1186, 1148 and 744kg/hr for napier grass, corn stalks and rice straw, respectively. Corn stalks required the highest power demand at 2.3kW engine would be adequate as power source. The chopper performance was comparable to higher cost commercial chippers in terms of capacity and specific energy.

• 한국수학교육학회지시리즈E:수학교육논문집
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• 제25권3호
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• pp.557-575
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• 2011

본 연구는 고등학교 수학에서 지도되고 있는 로그의 교수-학습 방법에 대한 새로운 관점과 방법을 고찰해보고 이를 통해 학교수학의 로그 지도에 대한 시사점을 제시하는데 목적이 있다. 이를 위하여 로그의 역사적 배경을 John Napier, 17세기 과학에 대한 로그의 영향, 그리고 로그계산자와 로그계산 방법을 중심으로 살펴보았다. 이런 배경과 함께 로그의 교수-학습 방법에 대한 고찰에서는 함수 개념을 이용한 로그의 도입, 상용로그를 이용한 로그계산, 밑의 변환 공식에 대해서 고찰하였다. 이런 역사적, 교수방법적 고찰을 통하여 학교수학에서 로그 지도에 대한 여섯 가지 시사점을 제시하였다.

• Animal Bioscience
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• 제34권8호
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• pp.1415-1424
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• 2021

Objective: Portable laser methane detectors (LMDs) may be an economical means of estimating CH₄ emissions from ruminants. We validated an LMD-based approach and then used that approach to evaluate CH₄ emissions from indigenous dairy cows in a dryland area of Ethiopia. Methods: First, we validated our LMD-based approach in Simmental crossbred beef cattle (n = 2) housed in respiration chambers and fed either a high- or low-concentrate diet. From the results of the validation, we constructed an estimation equation to determine CH₄ emissions from LMD CH₄ concentrations. Next, we used our validated LMD approach to examine CH₄ emissions in Fogera dairy cows grazed for 8 h/d (GG, n = 4), fed indoors on natural-grassland hay (CG1, n = 4), or fed indoors on Napier-grass (Pennisetum purpureum) hay (CG2, n = 4). All the cows were supplemented with concentrate feed. Results: The exhaled CH₄ concentrations measured by LMD were linearly correlated with the CH₄ emissions determined by infrared-absorption-based gas analyzer (r² = 0.55). The estimation equation used to determine CH₄ emissions (y, mg/min) from LMD CH₄ concentrations (x, ppm m) was y = 0.4259x+38.61. Daily CH₄ emissions of Fogera cows estimated by using the equation did not differ among the three groups; however, a numerically greater milk yield was obtained from the CG2 cows than from the GG cows, suggesting that Napier-grass hay might be better than natural-grassland hay for indoor feeding. The CG1 cows had higher CH₄ emissions per feed intake than the other groups, without significant increases in milk yield and body-weight gain, suggesting that natural-grassland hay cannot be recommended for indoor-fed cows. Conclusion: These findings demonstrate the potential of using LMDs to valuate feeding regimens rapidly and economically for dairy cows in areas under financial constraint, while taking CH₄ emissions into consideration.

• Asian-Australasian Journal of Animal Sciences
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• 제33권5호
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• pp.763-769
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• 2020

Objective: The experiment was conducted to study the effect of rambutan (Nephelium lappaceum) fruit peel powder (RP) on feed consumption, digestibility of nutrients, ruminal fermentation dynamics and microbial population in Thai breed cattle. Methods: Four, 2-year old (250±15 kg) beef bull crossbreds (75% Brahman×25% local breed) were allotted to experimental treatments using a 4×4 Latin square design. Four dietary supplementation treatments were imposed; non-supplementation (control, T1); supplementation of RP fed at 2% of dry matter intake (DMI) (low, T2); supplementation of RP fed at 4% of DMI (medium, T3) and supplementation of RP fed at 6% of DMI (high, T4). All cattle were given a concentrate supplement at 1% of body weight while Napier grass was provided as a free choice. Results: The findings revealed that RP supplementation did not negatively affect (p>0.05) DMI of Napier grass, while RP intake and total DMI were the greatest in the RP supplementation at 4% and 6% DMI. Nevertheless, the nutrients (dry matter, organic matter, crude protein, neutral detergent fiber, and acid detergent fiber) digestibilities were not changed in the RP supplementation groups. Rumen fermentation parameters especially those of total volatile fatty acids, acetate and butyrate were not significantly changed. However, the propionate concentration was remarkably increased (p<0.05) in the RP supplementation. Notably, the ratio of acetate to propionate, the number of protozoa, as well as the methane estimation were significantly reduced in the RP supplemented groups (4% and 6% of DMI), while the counts of bacteria was not altered. Conclusion: Supplementation of RP (4% of DMI) improved rumen propionate production, reduced protozoal population and methane estimation (p<0.05) without a negative effect on feed consumption and nutrients total tract digestibilities in beef cattle. Using dietary rambutan fruit peel powder has potential promise as a rumen regulator.

• 한국초지조사료학회지
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• 제12권4호
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• pp.218-225
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• 1992

대관령지역에서 orehardgrass 17개 품종을 공시하 여 월동성지수와 상대경수출현율당 개체중에 의한 월동성의 품종간 차이를 비교함과 동시에 월동성검 정에 유효한 형질을 평가하고자 하였다. 1. 월동전 유식물체의 초세는 l번초의 개체중과 상대경수출현융당 개체중과는 유의한 부의 상관을 나타내었다 2. I번초의 개체중은 개체당경수,I경중,포장생존율, 출수율 및 출수경중과는 유의한 정상관이 인정되었다 3. I번초의 개체중은 월동성지수와는 5%수준, 상대 경수출현율당 개체중과는 1%수준의 유의한 정상관이 인정되었다. 4 .월동성지수는 포장생존율과 상대경수출현융당 개체중은 1경중 및 출수경중과 각각 1%수준의 정상 관이 인정되었다. 5 월동성 지수에 의하여 2품종군으로 분류할 수 있는데 월동성지수가 100이상인 품종에는 Hallmark, lna, Rancho, Amba, Filippa, Sparta, Hokuto, Kitam midori, Okamidori, Wasemidori, Shinyo, Potomac 그리고 Summer-green의 13개 품종이 포함되었고, 월동성지수가 100미만의 품종에는 Able, Juno, Napier 그리고 Jesper의 4개 품종이 포함되었다. 6. 상대경수출현융당 개체중에 의해서도 2 품종군 으로 분류할 수 있는데 상대경수출현율당 개체중이 l 1.0이 상의 품종에 는 Amba, Okamidori, Wasemidori 그리고 Summer-green의 4개 품종이 포함되었고, 100미만의 품종에는 Able, Hallmark, lna, Juno,Napier, Rancho, Filippa, Jesper, Sparta, Hokuto, K Kitamidori, Shinyo 그리고 Potomac의 13개 품종이 포함되였다 상대경수출현율당 개체중이 1.0이상으로 월동성이 높은 품종은 Amba, Okamidori, Wasemidori, Sum¬m$\varepsilon$r-gr$\varepsilon$en 의 4개 품종이었으며 이 들 품종들의 월 동 성지수는 100이상을 나타내였다. 7 .상대경수출현율당 개체중은 대관령지역(해발 8 800m)에서 월동성을 나타내는 유효한 생태적인 형질 이라고 생각되었다.

• Asian-Australasian Journal of Animal Sciences
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• 제14권7호
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• pp.956-959
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• 2001

Three perennial grasses, Napier (Pennisetum purpureum), Andropogan (Andropogan gayanus) and Para (Brachiria mutica), were grown at different hill heights dividing the hill slope into three regions (top, middle and bottom). The first two grasses gave the highest biomass yields (29.9 and 37.6 tonnes/ha/harvest, respectively) followed by Para (20.5 t/ha). No significant (p>0.05) changes in biomass yields of the grasses were found due to differences in hill heights. The grasses were harvested three times in the first year of cultivation. Maize and cowpea as sole crops or their intercrops were cultivated in the plain land and the intercrop gave the highest biomass yield (46.7 t/ha, p<0.05). The biomass produced was successfully ensiled in the underground pits at the hill tops.

• Journal of the korean society of oceanography
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• 제38권4호
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• pp.185-210
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• 2003

This paper describes and assesses the parameterisation of MP, the microplankton compartment of the carbon­nitrogen microplankton­detritus model. The compartment is 'the microbial loop in a box' and includes pelagic bacteria and protozoa as well as phytoplankton. The paper presents equations and parameter values for the autotroph and microheterotroph components of the microplankton. Equations and parameter values for the microplankton as a whole are derived on the assumption of a constant 'heterotroph fraction'. The autotroph equations of MP allow variation in the ratios of nutrient elements to carbon, and are largely those of the 'cell­quota, threshold­limitation' algal growth model, which can deal with potential control of growth by several nutrients and light. The heterotroph equations, in contrast, assume a constant elemental composition. Nitrogen is used as the limiting nutrient in most of the model description, and is special in that MP links chlorophyll concentration to the autotroph nitrogen quota.

• Journal of the korean society of oceanography
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• 제39권2호
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• pp.136-147
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• 2004

Different model formulations in available models were compared with Microplankton-Detritus (MPB) model, and well documented FDM and ERSEM models were the candidate for these comparison. Different formulations in both candidate models were expressed in terms of MPD parameterization. Even though there are differences in the control of autotroph growth among models, it was found that some of the more important microplankton parameters expressed incomparable terms have broadly similar values in all the models. However, an important difference was proved to be the direct contribution of microheterotrophs to the Detritus compartment in FDM and ERSEM, whereas in MPD microplankton biomass passes to Detritus only by way of mesozooplankton grazing.