• Asian-Australasian Journal of Animal Sciences
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• 제27권9호
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• pp.1311-1318
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• 2014

This study was designed to investigate the effects of basal diets supplemented with a clay product consisting of zeolite and attapulgite (ZA) at 1:1 ratio on growth performance, digestibility of feed nutrients, activities of digestive enzymes in small intestine and intestinal health in broiler chickens. In experiment 1, 112 one-day-old male chickens were randomly divided into 2 groups with 8 replicates of 7 chickens each. In experiment 2, 84 one-day-old male chickens were randomly allocated into 2 groups consisting 6 replicates of 7 chickens each. The experimental diets both consisted of a maize-soybean basal control diet supplemented with 0% or 2% ZA. The diets were fed from 1 to 42 days of age. The results showed that ZA supplementation could increase body weight gain (BWG) and feed intake (FI), but had no significant effect on feed conversion ratio. The apparent digestibility values of crude protein and gross energy were significantly increased (p<0.05) by ZA from 14 to 16 d and 35 to 37 d. Dietary ZA treatment significantly increased (p<0.05) the activities of amylase, lipase and trypsin in jejunal digesta and the activities of maltase and sucrase in jejunal mucosa on days 21 and 42. The ZA supplementation also significantly increased (p<0.05) the catalase activity, reduced (p<0.05) the malondialdehyde concentration in the jejunal mucosa. In addition, a decrease of serum diamine oxidase activity and an increase (p<0.05) in concentration of secretory immunoglobulin A in jejunal mucosa were observed in birds treated with ZA on 21 and 42 days. It is concluded that ZA supplementation (2%) could partially improve the growth performance by increasing BWG and FI. This improvement was achieved through increasing the secretion of digestive enzymes, enhancing the digestibilites of nutrients, promoting intestinal health of broiler chickens.

• 농약과학회지
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• 제12권3호
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• pp.207-214
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• 2008

내분비장애 추정물질의 분류를 위해 많은 시험법이 연구되고 있는데 추후 내분비장애 추정물질로 분류된 기등록 농약에 대한 자료요구 또는 신규 등록농약에 대한 등록기준의 추가 등을 고려하여 OECD와 EPA에서 권장하는 시험법을 확립하고자 본 연구를 수행하였다. 시험약제를 30일간 경구 투여하여 조사한 결과, alachlor 투여 수컷에서 25 mg/kg/day, 50 mg/kg/day에서 고환과 갑성선의 중량이 증가하였다. Alachlor 투여 암컷에서는 질의 중량이 25, 50 mg/kg/day에서 감소하였고 25 mg/kg/day에서 갑상선의 중량이 감소하였다. Alachlor 투여 암컷 25, 50 mg/kg/day에서 주요 갑상선 호르몬인 T4와 성호르몬 testosterone이 감소하였다. 따라서 pubertal assay 결과 alachlor는 갑상선 호르몬성 영향이 의심되었다. 시험세포를 이용한 시험 결과, 시험약제를 1 nM에서 1000 nM까지 처리하였을 때 음성대조군과 비교하여 alachlor는 100-134%의 갑상선 호르몬성 영향을 나타내었다. 따라서 세포를 이용한 시험에서는 alachlor에 의한 갑상선 호르몬성 영향이 나타나는 것으로 판단되었다. 항갑상선 호르몬성 영향 시험에서는 시험약제 100 nM과 T4의 혼합 처리시 alachlor는 항갑상선 호르몬성 영향은 나타나지 않았다.

• 농약과학회지
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• 제2권2호
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• pp.53-58
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• 1998

벼멸구에 대해 살충성이 있는 2-carbomethoxy-4-chlorodiethyl phosphate를 신농약으로 개발할 목적으로 변이원성 시험, 즉 유전자복귀돌연변이, 염색체이상 및 소핵시험을 수행하였다. Salmonella typhimurium을 이용한 복귀돌연변이원성을 TA1535, TA1537, TA98과 TA100 균주를 이용하여 시험한 결과 대사활성화물질(S-9mix)의 첨가여부에 관계없이 유전자에 이상을 미치지 않았으며, CHL세포에 대한 세포독성은 EMEM 배지에서 $LC_{50}$이 $200{\mu}g/m{\ell}$이었으므로 $200{\mu}g/m{\ell}$을 최고농도로 공비2, 농도4로 염색체이상시험을 실시한 결과 200과 $100{\mu}g/m{\ell}$에서 이상세포가 나타났으나 양성으로 판정되지는 않았다. 2-Carbomethoxy-4-chlorodiethyl phosphate가 ICR 마우스의 골수세포에 미치는 영향을 탐색하기 위해 실시한 소핵시험에서도 음성대조, 양성대조 및 시험물질처리 군에서 PCE 및 MNPCE의 출현율이 모두 정상범위 내에 있어서 2-carbomethoxy-4-chlorodiethyl phosphate가 ICR 마우스의 골수세포에 소핵을 형성시키지 않는 것이 확인되었다. 이상의 결과를 종합할 때 2-carbomethoxy-4-chlorodiethyl phosphate는 미생물, 배양세포 그리고 생체 내에서 유전물질에 영향을 주지 않는 물질인 것으로 판단된다.

• Asian-Australasian Journal of Animal Sciences
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• 제32권6호
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• pp.834-841
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• 2019

Objective: This study was conducted to investigate the effects of in ovo feeding (IOF) of creatine pyruvate (CrPyr) on the energy metabolism in thigh muscle of embryos and neonatal broilers. Methods: A total of 960 eggs were randomly assigned to three treatments: i) non-injected control group, ii) saline group injected with 0.6 mL of physiological saline (0.75%), and iii) CrPyr group injected with 0.6 mL of physiologi-cal saline (0.75%) containing 12 mg CrPyr/egg on 17.5 d of incubation. After hatching, 120 male chicks (close to the average body weight of the pooled group) in each group were randomly assigned to eight replications. The feeding experiment lasted 7 days. Results: The results showed that IOF of CrPyr increased glucose concentrations in the thigh muscle of broilers on 2 d after injection (p<0.05). Compared with the control and saline groups, the concentration of creatine in CrPyr group was increased on 2 d after injection and the day of hatch (p<0.05). Moreover, IOF of CrPyr increased the creatine kinase activity at hatch and increased the activities of hexokinase and pyruvate kinase on 2 d after injection and the day of hatch (p<0.05). Chicks in CrPyr group showed higher mRNA expressions of glucose transporter 3 (GLUT3) and GLUT8 on the day of hatch (p<0.05). Conclusion: These results demonstrated that IOF of CrPyr was beneficial to enhance muscle energy reserves of em-bryos and hatchlings.

• Animal Bioscience
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• 제37권1호
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• pp.28-38
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• 2024

Objective: Tibetan chickens, which have unique adaptations to extreme high-altitude environments, exhibit phenotypic and physiological characteristics that are distinct from those of lowland chickens. However, the mechanisms underlying hypoxic adaptation in the liver of chickens remain unknown. Methods: RNA-sequencing (RNA-Seq) technology was used to assess the differentially expressed genes (DEGs) involved in hypoxia adaptation in highland chickens (native Tibetan chicken [HT]) and lowland chickens (Langshan chicken [LS], Beijing You chicken [BJ], Qingyuan Partridge chicken [QY], and Chahua chicken [CH]). Results: A total of 352 co-DEGs were specifically screened between HT and four native lowland chicken breeds. Gene ontology and Kyoto encyclopedia of genes and genomes enrichment analyses indicated that these co-DEGs were widely involved in lipid metabolism processes, such as the peroxisome proliferator-activated receptors (PPAR) signaling pathway, fatty acid degradation, fatty acid metabolism and fatty acid biosynthesis. To further determine the relationship from the 352 co-DEGs, protein-protein interaction network was carried out and identified eight genes (ACSL1, CPT1A, ACOX1, PPARC1A, SCD, ACSBG2, ACACA, and FASN) as the potential regulating genes that are responsible for the altitude difference between the HT and other four lowland chicken breeds. Conclusion: This study provides novel insights into the molecular mechanisms regulating hypoxia adaptation via lipid metabolism in Tibetan chickens and other highland animals.

• 분석과학
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• 제34권1호
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• pp.1-8
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• 2021

An analytical method was developed and optimized for the quantification of a plant growth regulator, 2,6-diisopropylnaphthalene (2,6-DIPN), in agricultural products using gas chromatography-tandem mass spectrometry. The samples were extracted, partitioned, and were purified using a Florisil® cartridge. To validate the analytical method, its specificity, linearity, limit of detection (LOD) and limit of quantification (LOQ) of the instrument, LOQ of the analytical method (MLOQ), accuracy, and repeatability were considered. The method displayed excellent results during validation, and is suitable for the determination and quantification of the low residual levels of the analyte in the agricultural samples. All of the results with the optimized method were satisfactory and within the criteria ranges requested in the Codex Alimentarius Commission guidelines and the Ministry of Food and Drug Safety guidelines for pesticide residue analysis. The developed method is simple and accurate and can be used as a basis for safety management of 2,6-DIPN.

• 한국환경농학회지
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• 제31권2호
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• pp.146-151
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• 2012

BACKGROUND: This study was conducted to develop analytical method for picoxystrobin in agricultural commodities using GC/ECD and GC/MS. METHODS AND RESULTS: Each steps of analytical method were optimized for determining picoxystrobin residues in various agricultural commodities. The developed methods include acetone extraction, n-hexane/saline water partition and florisil column chromatography for analysis of all samples (apple, potato, green pepper, hulled rice and soybean), and in addition to these steps, solid phase extraction (SPE) was used for analysis of green pepper and n-hexane/acetonitrile partition was used for analysis of hulled rice and soybean. The instrumental conditions were tested for quantitation in GC/ECD and for confirmation in GC/MS. Recovery was in the range of 86~109% with RSD ${\leq}$10.2% and the quantitation limits (LOQ) of method were 0.025 mg/kg in all agricultural commodities. CONCLUSION: The result showed that the developed method can be used to determine picoxystrobin residue in agricultural commodities.

• 한국농공학회논문집
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• 제60권1호
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• pp.121-131
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• 2018

Past climate change influences multiple environmental aspects, certain of which are specifically related to agricultural water resources such as water supply and demand. Changes on rainfall and hydrologic patterns can increases the occurrence of reservoir water shortage and affect the future availability of agricultural water resources. It is a main concern for sustainable development in agricultural water resources management to evaluate adaptation capability of water supply under the changing climate and farming methods in paddy field. The purpose of this study is an evaluation method of design frequency of drought and water supply safety for agricultural reservoirs to investigate evidence of climate change occurrences at a local scale. Thus, it is a recommended practice in the development of water supply management strategies on reservoir operation under changing climate and farming methods in paddy field.

• 농약과학회지
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• 제10권2호
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• pp.99-106
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• 2006

노지와 시설하우스에 재배중인 고추에 살포한 chlorothalonil과 imidaclopid는 시설하우스보다 노지에서 분해가 빨랐는데 시험기간 중 강우가 없었던 점을 고려하면 이는 주로 이슬에 의한 세척과 광분해에 의한 영향으로 추측되었다. 고추품종별 농약 잔류량 변화는 일정한 경향을 보이지 않았는데 이는 고추가 연속수확작물이고 또한 고추가 고춧잎 속에서 생육하여 농약이 골고루 묻지 않았기 때문으로 판단되었다. 풋고추를 절였을 경우에는 농약에 따라 약 $30{\sim}71%$의 잔류량 경감효과가 있었으며, 꽈리고추를 볶았을 경우에는 $20{\sim}41%$의 경감효과가 있었다. 또한 esfenvalerate와 imidacloprid를 살포한 홍고추를 이용하여 고추장을 담가 2개월간 발효시켰을 경우에는 고추장에서 농약이 검출되지 않았다. 수확한 고춧잎 중 잔류농약은 물세척에 의해 $22{\sim}37%$, 데침에 의해 $74{\sim}95%$, 데침 후 건조에 의해 $17{\sim}55%$의 고춧잎 중 잔류농약 경감율을 보였다.

• 한국농공학회논문집
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• 제65권6호
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• pp.23-35
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• 2023

In this study, we developed a method to determine the flood-limited water levels of agricultural reservoirs, considering both their irrigation and flood control functions. Irrigation safety and flood safety indices were defined to be applied to various reservoirs, allowing for a comprehensive assessment of the irrigation and flood control properties. Seasonal flood-limited water level scenarios were established to represent the temporal characteristics of rainfall and agricultural water supply and the safety indices were analyzed according to these scenarios. The optimal scenarios were derived using a schematic solution based on Pareto front analysis. The method was applied to Obong, Yedang, and Myogok reservoirs, and the results showed that the characteristics of each reservoir were well represented in the safety indices. The irrigation safety of Obong reservoir was found to be significantly influenced by the late-stage flood-limited water level, while those of Yedang and Myogok reservoir were primarily affected by the early and mid-stage flood-limited water levels. The values of irrigation safety and flood safety indices for each scenario were plotted as points on the coordinate plane, and the optimal flood-limited water levels were selected from the Pareto front. The storage ratio of the optimal flood-limited water levels for the early, mid, and late stages were 65-70%, 70%, and 75% for Obong reservoir, 75%, 70-75%, and 65-70% for Yedang reservoir, and 75-80%, 70%, and 50% for Myogok reservoir. We expect that the method developed in this study will facilitate efficient reservoir operations.