• Asian-Australasian Journal of Animal Sciences
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• 제14권11호
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• pp.1598-1604
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• 2001

Eight $12.4{\pm}0.6kg$ initial body weight crossbred barrows were used to determine the effect of soybean galactooligosaccharides on nutrient and energy digestibility, and digesta transit time. Four dietary treatments were utilized in this trial. Treatment one was a corn-soybean meal based diet (SBM) containing raffinose and stachyose at the levels of 0.16% and 0.75%, respectively. Treatment two (control) was a corn-HP300 (soybean concentrate protein) diet. In treatments three and four, 1.1% and 2.2% commercial stachyose was added to the control diet to provide total dietary stachyose at the levels of 1% and 2%, respectively. The soybean galactooligosaccharides (raffinose + stachyose) level in treatment one was slightly lower compared to that in treatment three. Three collection periods were run with two pigs for each treatment/period. There was a 4 d adjustment period followed by a 3 d collection period. The results showed that the nitrogen retention (86.79%) of pigs fed treatment two diet was higher than that of pigs fed treatment one by 5.2% (p<0.05). The nitrogen retention of treatment three was intermediate 83.09%. The apparent fecal digestibility of all amino acids in treatment two was numerically highest, followed by treatments three and four. However, there were no significant difference among groups (p>0.05). The dry matter (DM), organic matter (OM), crude protein (CP), and crude fiber (CF) digestibility numerically decreased as the soybean galactooligosaccharides level increased, but were not significantly different (p>0.05). Chromium content in feces (from the inclusion of 0.3% chromic oxide in the diets) differed among treatments (p<0.05) at 15 h, 18 h, and 21 h after eating. This showed that the digesta transit time was differed significantly among treatments. Treatment four was the shortest, followed by treatment three, SBM and control. The results demonstrated that in the absence of antinutritional factors and soybean antigen protein, inclusion of 1% and 2% stachyose in corn-HP300 diet has no significant effect on the digestibility of DM, OM, CP, CF and amino acids. When the soybean galactooligosaccharide level in diet one and diet three were adjusted to be almost the same, antinutritional factors such as trypsin inhibitor and soybean antigen protein could decrease the nutrient digestibility and nitrogen retention rate of diet. High levels of soybean galactooligosaccharides shortened the digesta transit time in the intestinal tract. This trial suggested that the total level of soybean galactooligosaccharides (stachyose+raffinose) in the weanling piglet diet is better not to exceed 1% when common soybean meal is used as main protein source.

• Asian-Australasian Journal of Animal Sciences
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• 제30권10호
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• pp.1435-1441
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• 2017

Objective: The objective of this study was to determine the effect of adding water to total mixed ration (TMR) on fresh water intake, nutrient digestibility, wool cortisol, and blood indices in Corriedale ewes under hot and humid conditions. Methods: Nine non-pregnant Corriedale ewes (ave. body weight = $41{\pm}3.5kg$) were individually fed diets based on maintenance requirements in metabolic crates. Ewes were assigned to three treatment groups according to a triplicate $3{\times}3$ Latin Square design for 3 periods of 21 days duration each (9 ewes per treatment, 27 replications). Treatments were TMR (crude protein [CP] = 16.1, total digestible nutrients = 69.1%) moisture levels for 40%, 50%, and 60%. Results: No differences were found in body weight gain among all treatment groups (p>0.05). Nitrogen balance including digestible N, retained N, and urinary and fecal N showed no change among the treatment groups (p>0.05). Fresh water intake was the lower in 50% TMR moisture group than in the other groups (p<0.05). Other than ether extract which was higher in 60% TMR moisture group (p<0.05) the differences among nutrient digestibilities including CP, organic matter, dry matter, neutral detergent fiber, acid detergent fiber, and non-fiber carbohydrate were not significant (p>0.05). No significant difference was observed for serum protein, blood urea nitrogen, glucose, and triglyceride among the treatment groups (p>0.05). Wool and blood cortisol were not different among the treatment groups (p>0.05). Blood hematology including red blood cell, white blood cells, hemoglobin, hematocrit, basophils, and eosinophils were not different among the treatment groups (p>0.05). Conclusion: It is concluded that TMR moisture at 40%, 50%, and 60% had no effects on N balance parameters, and nutrient digestibilities except for the ether extract under hot and humid conditions. Additionally there were no effects on stress conditions include wool cortisol, as well as blood cortisol levels of ewes.

• Asian-Australasian Journal of Animal Sciences
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• 제30권12호
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• pp.1702-1710
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• 2017

Objective: The study examined the effect of condensed tannins (CT) containing Ficus infectoria and Psidium guajava leaf meal mixture (LMM) supplementation on nutrient metabolism, methane emission and performance of lambs. Methods: Twenty four lambs of ~6 months age (average body weight $10.1{\pm}0.60kg$) were randomly divided into 4 dietary treatments (CT-0, CT-1, CT-1.5, and CT-2 containing 0, 1.0, 1.5, and 2.0 percent CT through LMM, respectively) consisting of 6 lambs each in a completely randomized design. All the lambs were offered a basal diet of wheat straw ad libitum, oat hay (100 g/d) along with required amount of concentrate mixture to meet their nutrient requirements for a period of 6 months. After 3 months of experimental feeding, a metabolism trial of 6 days duration was conducted on all 24 lambs to determine nutrient digestibility and nitrogen balance. Urinary excretion of purine derivatives and microbial protein synthesis were determined using high performance liquid chromatography. Respiration chamber study was started at the mid of 5th month of experimental feeding trial. Whole energy balance trials were conducted on individual lamb one after the other, in an open circuit respiration calorimeter. Results: Intake of dry matter and organic matter (g/d) was significantly (p<0.05) higher in CT-1.5 than control. Digestibility of various nutrients did not differ irrespective of treatments. Nitrogen retention and microbial nitrogen synthesis (g/d) was significantly (p<0.01) higher in CT-1.5 and CT-2 groups relative to CT-0.Total body weight gain (kg) and average daily gain (g) were significantly (linear, p<0.01) higher in CT-1.5 followed by CT-1 and CT-0, respectively. Feed conversion ratio (FCR) by lambs was significantly (linear, p<0.01) better in CT-1.5 followed by CT-2 and CT-0, respectively. Total wool yield (g; g/d) was linearly (p<0.05) higher for CT-1.5 than CT-0. Methane emission was linearly decreased (p<0.05) in CT groups and reduction was highest (p<0.01) in CT-2 followed by CT-1.5 and CT-1. Methane energy (kcal/d) was linearly decreased (p<0.05) in CT groups. Conclusion: The CT supplementation at 1% to 2% of the diet through Ficus infectoria and Psidium guajava LMM significantly improved nitrogen metabolism, growth performance, wool yield, FCR and reduced methane emission by lambs.

• 한국환경농학회지
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• 제33권1호
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• pp.9-16
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• 2014

BACKGROUND: This study was conducted to investigate the effects of seeding timing and method of rye and/or hairy vetch on seasonal soil and foliar nutrient concentrations as well as fruit quality in a pesticide-free pear orchard. METHODS AND RESULTS: The treatments included as followed: single seeding of rye in September (Sep-Mono), November (Nov-Mono), and January (Jan-Mono), or mix seeding of rye+hairy vetch in November (Nov-Mix) and January (Jan-Mix), or sod culture as a control. Cover crops or vegetation was mown and mulched on the soil surface in April and May for two years. Nov-Mix treatment produced the highest dry matter weight of $12,070kg\;ha^{-1}$, with the lowest dry matter weight for sod culture ($6,520kg\;ha^{-1}$), following Jan-Mix ($7,030kg\;ha^{-1}$). Nov-Mix treatments increased potential amount of N, P, and K from the raw materials of the cover crops as well as improved soil physical properties. Nov-Mix treatments overall elevated soil pH, EC, organic matter, and $P_2O_5$ in May compared to other cover crop treatments or sod culture. The difference of the seasonal nutrient concentrations in leaves or fruit qualities were not consistently occurred amongst treatments. CONCLUSION: Nov-Mix treatments showed playing role in a substitute of a chemical fertilizer. Delayed seeding of cover crops such as Jan-Mix did not increase the potential dry matter production due to the short growing period, and the seeding time would affect the dry matter production of cover crops.

• 한국해양환경ㆍ에너지학회지
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• 제9권4호
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• pp.216-224
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• 2006

하계 가막만에서 발생하는 빈산소 수괴의 형성과정과 그 특성을 규명하기 위하여 2005년 6월 17일부터 2005년 9월 12일까지 주 간격으로 조사하였다. 표층 수온은 내만에서 만 입구로 갈수록 낮았으나, 저층 수온은 만 입구와 내만보다 만 중앙에서 높게 나타났다. 수괴의 수직적인 성층은 매우 발달하였으며, 수온약층은 수심 3-5m에서 관측되었다. 저층의 빈산소 수괴는 7월초에 내만 안쪽에서 나타났으며, 8월초에는 만 중앙부까지 확산되었다. 수괴의 평균투명도와 광소멸 계수($K_d$)는 각각 4.0m와 0.47로 나타났다. 저층의 영양염과 클로로필 ${\alpha}$ 농도는 표층보다 유의하게 높았으며, 만 입구보다 내만에서 높게 나타났다. 빈산소 수괴의 저층에서 퇴적물의 산소투과 깊이는 지극히 낮았으며, 산소소모율은 빈산소가 소멸된 수괴에서 보다 낮았다. 빈산소 수괴가 발생하는 기간동안 용존 산소 농도는 저층의 영양염 농도와 유의한 역 상관관계를 보였으나, 표층 영양염 농도와는 유의한 관계를 보이지 않았다. 저층에서 산소 감소의 촉진은 퇴적물에서 산소소모율 증가와 저층 부근에서 미생물에 의한 유기물 분해 때문인 것으로 판단되었다.

• 생명과학회지
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• 제29권11호
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• pp.1281-1293
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• 2019

근권은 식물 뿌리와 토양 미생물이 서로의 신호를 주고 받으며 끊임없이 상호반응하는 역동적인 장소이다. 근권 주위에서 식물의 생장과 생산성에 유익한 토양 미생물을 식물생장촉진근권미생물(Plant Growth Promoting Rhizobacteria, PGPR)이라 칭하며, 이 PGPR은 식물 전 생장기간동안 생물학적 및 비생물학적 스트레스에 대한 저항성, 식물 호르몬 조절, 영양분의 흡수와 이용 등에 영향을 끼침으로써 식물의 생장과 발달, 면역, 생산력 등 중요한 생명 과정에 관여한다. 그리고, PGPR은 식물 생장을 유도하는 2차 대사산물이나 휘발성 유기 화합물을 생산하고, 식물의 뿌리 역시 식물 유해한 인자 혹은 병원성 인자에 대항하여 자신을 보호하거나 토양 성질 개선을 위해, PGPR을 유인하고 정착시키기 위한 물질을 생산, 분비한다. 그러므로, 식물과 PGPR 사이의 상호작용은 필수적이면서도 상호의존적이다. 현재까지, PGPR에 대한 많은 연구는 직간접적 개념에 대하여 공통적 또는 다양한 조건들에서 여러 방식으로 PGPR의 기능을 밝히는 방향으로 전개되어 왔다. 본 총설에서는 세포분열과 팽창, 분화에 의한 식물의 생장과 발달의 촉진, 식물생장조절인자와 호르몬의 유도, 영양물질의 고정, 용해, 무기화를 촉진하기 위한 PGPR의 역할과 전략을 소개하였다. 또한 PGPR와 토양 미생물군의 효과에 대한 현재까지의 연구 정보를 요약하였다.

• Journal of Ecology and Environment
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• 제43권2호
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• pp.129-160
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• 2019

Background: Characterizing and describing soils and land use and make a suggestion for sustainable utilization of land resources in the Ethiopian Rift valley flat plain areas of Lake Chamo Sub-Basin (CSB) are essential. Objectives: To (1) characterize soils of experimental area according to World Reference Base Legend and assess the nature and extent of salinity problems; (2) characterize land use systems and their role in soil properties; and (3) identify best land use practices used for both environmental management and improve agricultural productivity. Methods: Twelve randomly collected soil samples were prepared from the above land uses into 120 composites and analyzed. Results: Organic carbon (OC) and total nitrogen (TN) were varied along different land uses and depleted from the surface soils. The soil units include Chernozems (41.67%), Kastanozems (25%), Solonchaks (16.67%), and Cambisols (16.67%). The identified land uses are annual crops (AA), perennial crops (PA), and natural forest (NF). Generally, organic carbon, total nitrogen, percentage base saturation (PBS), exchangeable (potassium, calcium, and magnesium), available phosphorus (P₂O₅), manganese, copper, and iron contents were decreased in cultivated soils. Soil salinity problem was observed in annuals. Annuals have less nutrient content compared to perennials in irrigated agriculture while it is greater in annuals under rainfed. Clay, total nitrogen, available phosphorus, and available potassium (K₂O) contents were correlated positively and highly significantly with organic carbon and electrical conductivity. Conclusion: Management practices that improve soil quality should be integrated with leguminous crops when the land is used for annual crops production.

• 대한토목학회논문집
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• 제13권1호
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• pp.233-241
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• 1993

도시 하수처리장에서 발생되는 반송수의 성상과 처리계통에서의 영향을 검토하기 위해 본 연구가 수행되었다. 각 단위 공정별 반송수의 유량과 분석자료를 이용하여 물질수지를 작성한 뒤 반송수의 특성을 결정하였으며 실험실 완전혼합 활성슬럿지 반응조를 현장 운전 조건과 유사한 방법으로 운전하여 반송수의 영향을 살펴보았다. 연구 결과 반송수의 유량은 유입원수량에 대해 1.2-1.8%로 적은 양이지만 높은 농도로 인하여 유기물과 영양소 부하량은 평균 부하시 20-30% 정도로 증가되고 있었으며 충격부하시는 40-70 %까지 증가되고 있었다. 혼합하수의 침전효율은 BOD 30%, SS 45%를 나타내고 있으나, 반송수에 의한 부하증가로 인해 BOD의 제거효율은 원수 기준시 10% 미만으로 떨어져 포기조에 큰 영향을 미치고 있었다. 즉, 반송수의 평균부하가 포기조에 유입되는 경우 반송수의 유입이 없는 경우에 비해 10%의 BOD 제거효율이 저하되었고 충격부하시는 80% 이상의 BOD 제거효율을 얻을 수 없었으며 50% 이하의 질산화율에 불과하였다.

• 한국작물학회지
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• 제50권5호
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• pp.325-331
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• 2005

Seedlings of two rice genotyopes, cvs. Ilpumbyeo and Gancheokbyeo, were exposed to 0, 50 and 100 mM NaCl in nutrient solution for nine days. Plants were collected at the interval of 3 days and organic and inorganic solutes in leaves and roots and antioxidative enzyme activity in leaves were determined. Under salinity, the accumulation of soluble sugars occurred considerably in the older leaves of stressed seedlings compared to younger leaves and roots. The endogenous Na+ contents markedly increased at higher NaCl concentration in leaves and roots of seedlings, though it was higher accumulated in roots. Salinity resulted in an excessive proline accumulation in the stressed plants. A more pronounced increase was observed in Gancheokbyeo leaves. SOD activity in Impumbyeo cannot found any remarkable change, whereas, in Gancheokbyeo, its activity was rapidly decreased. CAT and POD activities increased with an increase in NaCl concentration in both genotypes. In sum­mary, the high capacity of rice seedlings to overcome an unfavorable growth condition such salt stress appears to be related to an adequate partition of organic solutes between shoots and roots and to changes in absorption, transport and re-translocation of salts.

• 한국축산시설환경학회지
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• 제12권1호
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• pp.41-44
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• 2006

2중필름 온실계사에서 육계를 사육하였을 때 발생하는 계분을 처리할 수 있는 수동 교반형 퇴비화시스템을 개발하였으며, 교반빈도가 퇴비화 온도에 미치는 효과를 분석하였다. 병원균 사멸에 필요한 $55^{\circ}C$ 이상의 온도를 유지한 기간은 무교반에서 88시간 1회/4일의 교반에서는 179 시간, 1회/2일의 교반에서는 200 시간으로 교반회수가 빈번할수록 그 기간이 길어지는 것으로 나타났다.