• 제목/요약/키워드: Korean agriculture

검색결과 21,122건 처리시간 0.049초

전산유체역학을 이용한 표준 오리사 설계안에 대한 환기효율성 분석 (Analysis on Ventilation Efficiency of Standard Duck House using Computational Fluid Dynamics)

  • 여욱현;조예슬;권경석;하태환;박세준;김락우;이상연;이승노;이인복;서일환
    • 한국농공학회논문집
    • /
    • 제57권5호
    • /
    • pp.51-60
    • /
    • 2015
  • In Korea, 69.4 % of duck farms had utilized conventional plastic greenhouses. In this facilities, there are difficulties in controlling indoor environments for raising duck. High rearing density in duct farms also made the environmental control difficult resulting in getting more stressed making their immune system weaker. Therefore, a facility is needed to having structurally enough solidity and high efficiency on the environmental control. So, new design plans of duck house have recently been conducted by National Institute of Animal Science in Korea. As a study in advance to establish standard, computational fluid dynamics (CFD) was used to estimate the aerodynamic problems according to the designs by means of overall and regional ventilation efficiencies quantitatively and qualitatively. Tracer gas decay (TGD) method was used to calculate ventilation rate according to the structural characteristics of duck houses including installation of indoor circulation fan. The results showed that natural ventilation rate was averagely 164 % higher than typically designed ventilation rate, 1 AER ($min^{-1}$). Meanwhile, mechanically ventilated duck houses made 81.2 % of summer ventilation rate requirement. Therefore, it is urgent to develop a new duck house considering more structural safety as well as higher efficiency of environmental control.

윈치커튼식 계사의 시기 및 작업자 출입에 따른 분진 발생 농도 측정 연구 (Measurement of Dust Concentration in a Naturally Ventilated Broiler House according to Season and Worker's Access)

  • 조예슬;권경석;이인복;하태환;박세준;김락우;여욱현;이상연;이승노
    • 한국농공학회논문집
    • /
    • 제57권6호
    • /
    • pp.35-46
    • /
    • 2015
  • Improvement in domestic poultry production has a positive effect on the export competitiveness of the poultry industry. However, overproduction and enlargement of facilities to assure a supply increase a stocking density which make a poor environment in the broiler house. In particular, an intensive rearing environment is vulnerable to dust control that causes respiratory diseases, such as asthma, bronchitis, etc., to farmers and broilers. However, monitoring data and research for environment control are not adequate, and there are no air quality regulations in broiler houses in Korea. In this study, TSP, PM10, inhalable dust and respirable dust concentration were monitored according to season, age of broiler and broiler's activities. Air quality assessment was also performed in accordance with the threshold limit value by Donham et al. (2000). The TSP concentrations were 77.5 %, 219.7 % higher and PM10 concentrations were 121.2 %, 303.8 % higher when change of season and winter respectively than summer. There were significantly different concentrations according to season and age of broiler. Inhalable and respirable dust concentration were also clearly different according to the season and age of broiler. A high dust concentration was observed, specifically exceeding the threshold limit by 119 % in the winter. In the case of the broiler's motion was activity according to worker's access into the broiler house, concentration level was 769.6 % higher than broiler's motion was stable and exceeded the threshold limit. These results suggest that the worker should put on protective equipment to protect there's respiratory health in the broiler house.

Effects of Ambient Temperature on Growth Performance, Blood Metabolites, and Immune Cell Populations in Korean Cattle Steers

  • Kang, H.J.;Lee, I.K.;Piao, M.Y.;Gu, M.J.;Yun, C.H.;Kim, H.J.;Kim, K.H.;Baik, M.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • 제29권3호
    • /
    • pp.436-443
    • /
    • 2016
  • Exposure to cold may affect growth performance in accordance with the metabolic and immunological activities of animals. We evaluated whether ambient temperature affects growth performance, blood metabolites, and immune cell populations in Korean cattle. Eighteen Korean cattle steers with a mean age of 10 months and a mean weight of 277 kg were used. All steers were fed a growing stage-concentrate diet at a rate of 1.5% of body weight and Timothy hay ad libitum for 8 weeks. Experimental period 1 (P1) was for four weeks from March 7 to April 3 and period 2 (P2) was four weeks from April 4 to May 1. Mean ($8.7^{\circ}C$) and minimum ($1.0^{\circ}C$) indoor ambient temperatures during P1 were lower (p<0.001) than those ($13.0^{\circ}C$ and $6.2^{\circ}C$, respectively) during P2. Daily dry matter feed intake in both the concentrate diet and forage groups was higher (p<0.001) during P2 than P1. Average daily weight gain was higher (p<0.001) during P2 (1.38 kg/d) than P1 (1.13 kg/d). Feed efficiency during P2 was higher (p = 0.015) than P1. Blood was collected three times; on March 7, April 4, and May 2. Nonesterified fatty acids (NEFA) were higher on March 7 than April 4 and May 2. Blood cortisol, glucose, and triglyceride concentrations did not differ among months. Blood CD4+, CD8+, and CD4+CD25+ T cell percentages were higher, while CD8+CD25+ T cell percentage was lower, during the colder month of March than during May, suggesting that ambient temperature affects blood T cell populations. In conclusion, colder ambient temperature decreased growth and feed efficiency in Korean cattle steers. The higher circulating NEFA concentrations observed in March compared to April suggest that lipolysis may occur at colder ambient temperatures to generate heat and maintain body temperature, resulting in lower feed efficiency in March.

지속가능한 환경농업정책의 기본 방향 (Sustainable Development Policies on Environmental-Friendly Agriculture)

  • 허승욱
    • 한국유기농업학회지
    • /
    • 제11권3호
    • /
    • pp.37-53
    • /
    • 2003
  • The purpose of this study is to analyze policies on environmental-friendly agriculture(EFA) and find out some implications. As we know well, EFA contributes environmental substantiality by using organic production methods and provides consumers with a secure, safe nutritious food supply. As consumption of environmental-friendly agricultural products increasing, policies on EFA began in the 1990s and it has been generally expanded in Korea. The strategies for sustainable EFA aim to promote harmony among human beings and between humanity and nature require. In addition, support to develop marketing activities, regionalization, and political support must be further developed.

  • PDF