• Asian-Australasian Journal of Animal Sciences
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• 제22권10호
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• pp.1366-1376
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• 2009

Effect of sulfur (S) on utilization efficiency of fresh cassava foliage and cassava hay in dairy cows was evaluated using thirty-two $1^{st}-2^{nd}$ lactation Holstein-Friesian crossbred dairy cows. The experimental treatment was a 2${\times}$2 factorial arrangement in a randomized complete block design (RCBD) using two roughages (rice straw+fresh cassava foliage (FCF) and rice straw+cassava hay (CH)) and two elemental sulfur (S) levels (0.15 and 0.4% S of dry matter (DM)), respectively. Four dietary treatments (FCF+0.15, FCF+0.4, CH+0.15 and CH+0.4) were offered ad libitum in the form of a total mixed ration (TMR) with concentrate to roughage (chopped rice straw+chopped cassava foliage) ratio at 60:40. Fresh cassava foliage or cassava hay resulted in similar dry mater intake, rumen ecology parameters, total tract digestibility, blood chemistry, milk production and composition. However, HCN intake, blood and milk thiocyanate concentration were significantly higher (p<0.01) in cows fed fresh cassava foliage with no sign of potential toxicity. Dry matter intake, body weight changes, molar percentage of propionate in rumen, neutral detergent fiber (NDF) digestibility and nitrogen (N) retention of cows tended to be increased while DM digestibility (65.6, 72.7, 68.6 and 72.1% of total DM intake for the respective treatments), rumen bacteria population (1.4, 1.7, 1.6 and $1.7{\times}10^{11}$ cell/ml for respective treatments), fungal zoospore population (0.4, 0.6, 0.4 and $0.5{\times}10^{6}$ cell/ml for respective treatments), urinary allantoin (25.3, 28.0, 26.3 and 27.6 g/d for respective treatments), microbial N yield (136.0, 154.6, 142.8 and 151.3 g N/d for respective treatments) and milk protein content (3.4, 3.5, 3.2 and 3.5% for respective treatments) were significantly (p<0.05) higher in cows fed on supplemented sulfur at 0.4% of DM in comparison with 0.15% S-supplemented diets. Based on these results, it is concluded that cassava foliage could be used as a portion of roughage for dairy cows and supplementation of S would be nutritionally beneficial.

• 대한토목학회논문집
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• 제32권4B호
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• pp.253-259
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• 2012

하수에서 배양된 미세조류인 Chlorella vulgaris AG10032, Ankistrodesmus gracilis SAG278-2, Scenedesmus quadricauda AG10308은 오폐수에서 질소 및 인 제거가 우수하고 높은 지질을 함유하고 있어서, 오폐수에서 바이오연료나 기타 바이오 기반의 자원 회수에 유용한 생물자원이다. 오폐수 환경에는 다양한 인의 농도가 존재하는데, 인의 농도 특히 인 결핍조건에 따른 조류의 지방산 특성에 대한 정보가 매우 제한적이다. 이는 표준 분석방법이 정립되어 있지 않은데 일부 기인한다. 본 연구에서는 미생물의 지방산을 분석하는데 일반적으로 사용되는 무극성 컬럼법과 식물성 지질을 분석하는데 널리 사용되는 극성 WAX-type 컬럼 GC-FID 방법의 미세조류 지방산 분석 성능을 비교 분석하였고, 하수배양 조류에 적용이 보다 적절한 방법을 이용해서 인 결핍에 의한 조류 지방산 생성특성에 미치는 영향을 평가하였다. 그 결과 무극성 컬럼 방법에 비해 극성 WAX-type 컬럼 GC 방법이 $C_{18:3}$ 지방산과 같은 고불포화지방산을 규명하는 분석능력이 우수하였고, 실제 하수배양에서 배양 분리된 미세조류의 지방산 분석에 보다 정확한 결과를 보이었다. 이 WAX-type 컬럼 방법으로 인 결핍 영향을 분석한 결과, 미세조류의 지방산 조성과 생성량은 인의 농도 변화에 크게 영향을 받지 않음을 밝히었다.

• 농약과학회지
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• 제17권1호
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• pp.65-71
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• 2013

GC-NPD와 GC-ECD를 사용하여 잔류농약을 신속하게 정량 할 수 있는 변형 된 QuEChERS법이 시금치를 이용하여 검토되었다. 본 연구에서는 잔류농약 모니터링에서 주로 검출되며 GC로 측정 가능한 50가지 농약을 대상으로 하였다. 무농약 시금치를 이용하여 검량선을 작성하였으며, R2 값은 0.995 이상으로 모든 농약이 직선상을 나타내었다. 분석 농약의 검출한계는 0.001~0.1 ug/g로 나타났으며, 분석농약의 90% 이상이 0.05 ug/g 이하를 나타내었다. 정량한계는 0.001~0.32 ug/g로, 이는 농약의 잔류 허용기준치 보다 낮았다. Dichlorvos, propamocarb, chlorothalonil, dichlofluanid, cyhalothrin 그리고 fenvalerate를 제외하고는 대부분의 경우 회수율은 80~120%, RSD는 20% 이하로 나타났다. QuEChers는 기존 다중분석법과 비교해볼 때 일상적인 분석 시료에 응용했을 때 용매 사용량을 획기적으로 줄임으로써 친환경적 일뿐만 아니라 경제적이며 분석시간의 단축을 통해 유통 농산물의 안전성 확보에 기여할 수 있는 바가 크다고 할 수 있겠다.

• 한국동물위생학회지
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• 제38권3호
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• pp.155-162
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• 2015

The incidence of second-grade milk production in 9 dairy farms of South Korea was investigated from May 2011 to March 2012, and the serum composition of cows producing first- and second-grade milk in 14 farms including the 9 farms was analyzed. The incidence rate of second-grade milk production of 402 cows in nine dairy farms located in the central and southwestern regions of Korea was 15.4% with the highest rate being 34.4%. Seasonal morbidity was higher during late winter (February) and early summer (June) with the highest rate observed in February (32.6%) followed by November (33.3%). Second-grade milk was most frequently found within one month postpartum (34.1%) while only 3.5% was found during the first 60~90 days of lactating period (n=785, 5 herds). The morbidity increased thereafter (P<0.05) with the highest observed between 270~300 days of lactation (36.1%). The acidity was not significantly different between second-grade ($0.159{\pm}0.026%$) and first-grade milk ($0.158{\pm}0.027%$). Blood serum analysis of 371 cows in the 14 dairy farms indicated that aspartate aminotransferase (AST) level was significantly higher (P<0.001) in cows producing second-grade milk while albumin was significantly lower (P<0.001) than cows producing first-grade milk. Total protein and triglyceride was also significantly low along with glucose, non-esterified fatty acid and blood urea nitrogen in cows producing second-grade milk. Statistical analysis including sensitivity, specificity and positive/negative prediction values showed that lactating cows with high AST, low albumin, total protein and triglyceride levels in the serum tended to produce second-grade milk. It was concluded that serological parameters, especially live functional and metabolic-related serum compositions (AST, albumin, total protein and triglyceride), were significantly influenced in cows producing second-grade milk.

• 한국식품과학회지
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• 제48권3호
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• pp.275-283
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• 2016

본 연구는 스트렙토조토신에 의해 당뇨가 유발된 기억력 감퇴 모델에서 황칠나무 잎 열수추출물(DMW)의 학습 및 기억력 개선 효과를 평가하기 위해 수행되어졌다. 6주령의 SD-래트를 총 5개 군으로 분리 하였고, 11주간 24시간 간격으로 DMW를 100과 300 mg/kg b.w.농도로 경구 투여 하였으며, 양성대조군으로 donepezil (1 mg/kg b.w.)을 처리하였다. 7일 간격으로 체중과 혈당을 측정하였으며 STZ군에 비해 DMW군에서 유의한 체중 증가를 확인 할 수 있었다. 혈당 측정 결과 DMW군에서 6주째부터 혈당이 감소하기 시작하였으며, STZ군에 비해 유의적인 혈당 감소를 나타내었다. 혈청 내 바이오마커 측정 결과 혈중 포도당은 DMW 시료군에서 유의하게 감소하였고, 인슐린 호르몬 농도와 혈액 요소질소 또한 유의한 감소를 나타내었다. 간 기능 수치와 TG, TC, 그리고 크레아틴 농도에서는 각 군 간의 유의적 차이는 확인할 수 없었다. Morris water maze test와 passive avoidance test를 통해 STZ로 유도한 당뇨 모델에서 학습 및 기억력 장애를 확인 하였으며, DMW를 투여함으로서 학습 및 기억력이 유의적으로 회복, 증가한 것을 확인할 수 있었다. 또한 뇌 해마에서 Ach 함량과 AchE 활성 측정 결과, 당뇨 대조군에 비해 Ach 함량은 증가하였으며, AchE의 활성은 유의적으로 감소 한 것을 확인 하였다. 본 연구 결과로 STZ로 유도된 고 혈당 동물모델에서 황칠나무 잎 열수추출물(DMW)의 당뇨 개선 및 학습, 기억력 개선 효과를 확인 할 수 있었다. 이는 당뇨의 개선 효과와 더불어 고 혈당으로 인한 퇴행성 치매의 예방과 치료에도 일부 효과적일 것으로 사료된다. 이러한 연구 결과를 바탕으로 황칠 열수추출물(DMW)이 당뇨에 의한 학습 및 기억력의 저하에 있어 효과적인 대안으로서 보다 더 넓은 분야에서 연구되기를 바라는 바이다.

• 한국산업보건학회지
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• 제24권4호
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• pp.436-445
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• 2014

Objectives: Time-activity studies have become an integral part of comprehensive exposure assessment and personal exposure modeling. The aims of this study were to estimate exposure levels to nitrogen dioxide($NO_2$) and volatile organic compounds(VOCs), and to compare estimated exposures by using time-activity patterns and indoor air concentrations. Methods: The major microenvironments for office workers were selected using the Time-Use Survey conducted by the National Statistical Office in Korea in 2009. A total of 9,194 and 6,130 workers were recruited for weekdays and weekends, respectively, from the Time-Use Survey. It appears that workers were spending about 50% of their time in the house and about 30% of their time in other indoor areas during the weekdays. In addition, we analyzed the time-activity patterns of 20 office workers and indoor air concentrations in Daegu using a questionnaire and time-activity diary. Estimated exposures were compared with measured concentrations using the time-weighted average analysis of air pollutants. Conclusions: According to the time-activity pattern for the office workers, time spent in the residence indoors during the summer and winter have been shown as $11.12{\pm}2.20$ hours and $12.48{\pm}1.77$ hours, respectively, which indicates higher hours in the winter. Time spent in the office in the summer has been shown to be 1.5 hours higher than in the winter. The target pollutants demonstrate a positive correlation ($R^2=0.076{\sim}0.553$)in the personal exposure results derived from direct measurement and estimated personal exposure concentrations by applying the time activity pattern, as well as measured concentration of the partial environment to the TWA model. However, these correlations were not statistically significant. This may be explained by the difference being caused by other indoor environments, such as a bar, cafe, or diner.

• 한국대기환경학회지
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• 제28권5호
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• pp.571-580
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• 2012

Epidemiologic studies of air pollution need accurate exposure assessments at unmonitored locations. A land use regression (LUR) model has been used successfully for predicting traffic-related pollutants, although its application has been limited to Europe, North America, and a few Asian region. Therefore, we modeled traffic-related pollutants by LUR then examined whether LUR models could be constructed using a regulatory monitoring network in Metropolitan area in Korea. We used the annual-mean nitrogen dioxide ($NO_2$) in 2010 in the study area. Geographic variables that are considered to predict traffic-related pollutants were classified into four groups: road type, traffic intensity, land use, and elevation. Using geographical variables, we then constructed a model to predict the monitored levels of $NO_2$. The mean concentration of $NO_2$ was 30.71 ppb (standard deviation of 5.95) respectively. The final regression model for the $NO_2$ concentration included five independent variables. The LUR models resulted in $R^2$ of 0.59. The mean concentration of $NO_2$ of elementary schools was 34.04 ppb (standard deviation of 5.22) respectively. The present study showed that even if we used regulatory monitoring air quality data, we could estimate $NO_2$ moderately well. These analyses confirm the validity of land use regression modeling to assign exposures in epidemiological studies, and these models may be useful tools for assessing health effects of long-term exposure to traffic related pollution.

• Asian-Australasian Journal of Animal Sciences
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• 제8권3호
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• pp.281-287
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• 1995

A study was conducted to investigate the effect of different inclusion levels of urea treated whole-crop wheat silage (UWCWS) in grass silage based rations on the performance of growing beef cattle. The winter wheat (variety, Riband) was harvested (in the summer of 1991) at a dry matter proportion of 520 g/kg and treated with feed grade urea at the rate of 37 kg/tonne crop dry matter and preserved in a heavy duty plastic bag using a silo press. The urea treated whole crop wheat silage (UWCWS) was mixed with grass silage to replace 0.00 (S100), 0.33 (S33) and 0.67 (S67) parts of the forage dry matter and fed ad libitum in a cross over design to 18 Simmental X Holstein Friesian growing beef animals. Two energy sources {one high in starch, rolled barley (RB) and one high in digestible fibre, sugar beet pulp (SBP)} were fed to supply sufficient energy for the efficient use of nitrogen by the rumen micro-organisms. The data on DMIF (dry matter intake of forage), TDMI (total dry matter intake), DLWG (daily live weight gain), FCR (feed conversion ratio) were recorded and faecal samples were collected to determine the digestibility coefficients. Results revealed that with the inclusion of UWCW in the animals' diets the DMI of the forage was significantly increased (p < 0.05). The highest DMIF was found in the treatment "S33" ($6.28{\pm}0.25kg$) where 67% of the silage dry matter was replaced with the UWCW and the lowest value for DMIF was observed in the control treatment ($5.03{\pm}0.23kg$). The DLWG did not differ significantly between the treatments. However, treatment "S100" showed a trend towards a superior DLWG. Feed conversion ratio in the control treatment differed significantly from "S67" and "S33". The addition of the UWCW in the animals' diet resulted in the lower FCR There was no effect of type of energy supplement on any aspect of performance either overall or in interaction with grass silage: UWCWS ratio. The regression and correlation coefficients for DMIF (r = 5.22 + 0.0184x*), DLWG (r = $1.04-0.00086x^{NS}$) and FCR (r = 4.78 = 0.022x*) on the inclusion of UWCW in the diet were calculated. The effect of the inclusion of UWCW on the overall digestibility coefficients was significant (p < 0.05). The addition of the UWCWS in the diet decreased the digestibility of the DM, OM, ADF and NFE but effect on the protein digestibility was non significant. The results of present study suggests that a DLWG slightly over 1 kg can be achieved with UWCW during the store period (period in which animal performance targets are low especially during winter) and the prediction of ME was overestimated as the high intake of DM did not reflect in improved animal performance.

• Asian-Australasian Journal of Animal Sciences
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• 제24권12호
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• pp.1681-1689
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• 2011

The beneficial effects of tea catechins (TCs) are related not only to their antioxidant potential but also to the improvement of animal meat quality. In this study, we assessed the effects of dietary TC supplementation on plasma biochemical parameters, hormone responses, and glutathione redox status in goats. Forty Liuyang goats were randomly divided into four equal groups (10 animals/group) that were assigned to four experimental diets with TC supplementation at 4 levels (0, 2,000, 3,000 or 4,000 mg TC/kg DM feed). After a 60-day feeding trial, all goats were slaughtered and sampled. Dietary TC treatment had no significant effect on blood biochemical parameters, however, low-density lipoprotein cholesterol (p<0.001), triglyceride (p<0.01), plasma urea nitrogen (p<0.01), and glucose (p<0.001) decreased and total protein (p<0.01) and albumin (p<0.05) increased with the feeding time extension, and day 20 was the turning point for most of changes. Interactions were found in glutathione (p<0.001) and the ratio of reduced and oxidized glutathione (p<0.05) in whole blood between treatment and feeding time. Oxidized glutathione in blood was reduced (p<0.05) by 2,000 mg TC/kg feed supplementation, and a similar result was observed in longissimus dorsi muscle. Though plasma glutathione peroxidase (p<0.01) and glutathione reductase (p<0.05) activities were affected by treatment and feeding time interactions, and glutathione S-transferases activity increased with feeding day extension, no changed values appeared in longissimus dorsi muscle. In conclusion, dietary TC supplementation affected the concentrations of some blood metabolites and accelerated GSH depletion in the blood of goats. In terms of less high-density lipoprotein cholesterol, the highest insulin and IGF-I concentrations, the highest ratio of reduced and oxidized glutathione in plasma, the dosage of 2,000 mg TC/kg feed might be desirable for growing goats to prevent glutathione depletion and keep normal physiological metabolism.

• Asian-Australasian Journal of Animal Sciences
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• 제27권11호
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• pp.1562-1570
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• 2014

The effects of Lactobacillus mucosae (L. mucosae), a potential direct fed microbial previously isolated from the rumen of Korean native goat, on the rumen fermentation profile of brewers grain were evaluated. Fermentation was conducted in serum bottles each containing 1% dry matter (DM) of the test substrate and either no L. mucosae (control), 1% 24 h broth culture of L. mucosae (T1), or 1% inoculation with the cell-free culture supernatant (T2). Each serum bottle was filled anaerobically with 100 mL of buffered rumen fluid and sealed prior to incubation for 0, 6, 12, 24, and 48 h from which fermentation parameters were monitored and the microbial diversity was evaluated. The results revealed that T1 had higher total gas production (65.00 mL) than the control (61.33 mL) and T2 (62.00 mL) (p<0.05) at 48 h. Consequently, T1 had significantly lower pH values (p<0.05) than the other groups at 48 h. Ammonia nitrogen ($NH_3$-N), individual and total volatile fatty acids (VFA) concentration and acetate:propionate ratio were higher in T1 and T2 than the control, but T1 and T2 were comparable for these parameters. Total methane ($CH_4$) production and carbon dioxide ($CO_2$) were highest in T1. The percent DM and organic matter digestibilities were comparable between all groups at all times of incubation. The total bacterial population was significantly higher in T1 (p<0.05) at 24 h, but then decreased to levels comparable to the control and T2 at 48 h. The denaturing gradient gel electrophoresis profile of the total bacterial 16s rRNA showed higher similarity between T1 and T2 at 24 h and between the control and T1 at 48 h. Overall, these results suggest that addition of L. mucosae and cell-free supernatant during the in vitro fermentation of dried brewers grain increases the VFA production, but has no effect on digestibility. The addition of L. mucosae can also increase the total bacterial population, but has no significant effect on the total microbial diversity. However, inoculation of the bacterium may increase $CH_4$ and $CO_2$ in vitro.