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1.
The relationship between commuting distances and where people work has been studied for urban contexts in both developed countries and developing countries. However, few studies have examined the situation in rural areas, and none look at commuting distances to non‐farm workplaces in rural areas of developing countries. This paper investigates how commuting distance, and thus accessibility, to local non‐farm work influences non‐farm employment and out‐migration from rural villages in Northeast Thailand. The main issues examined are: (i) the distance that rural residents travel to work in local non‐farm jobs; and (ii) the influence that local non‐farm employment has on the number of outmigrants from rural villages. The study finds: (i) distance between villages and non‐farm work sites impact the number of villagers who are employed in regular wage work; (ii) beyond 20 km villagers are less likely to travel to non‐farm employment using their own means of transportation; and (iii) employment in regular wage work decreases outmigration. The findings from this study contribute to the debates over the drivers of rural out‐migration, rural livelihood changes, and agrarian changes that are taking place in Southeast Asia.  相似文献   
2.
肉羊养殖逐渐向规模化方向发展,但是口蹄疫、小反刍兽疫、羊布病等疫病防控面临形势愈加严重。需要从羊场设计、加强饲养管理、消毒、驱虫、制定合理免疫程序加强防检疫工作等多方面采取综合防控措施,降低疫病风险,取得最大养殖效益。  相似文献   
3.
This work proposes a method for the statistical monitoring of the weekly weight of shrimp in a fish farm. The design of control charts for shrimp growth presents several challenges, the main ones being the presence of trend and autocorrelation. Several control charts are proposed, the most efficient being a chart based on the residuals of a second order autoregression whose parameters vary with the week. A control chart with less computational complexity is also provided. It is simply based on growth rates and works well at detecting negative weight changes. Real data from a large shrimp farm has been used for both the design and the evaluation.  相似文献   
4.
畜牧作为推动农业发展的动力,可促进其发展现代化农业,提高农民收入。但是,随着畜牧业发展,加剧粪污污染问题,应加强粪污处理及资源化利用,以达到保护环境的目的。该文主要从畜禽粪污处理和资源化利用重要性切入,分析目前粪污处理与资源化利用方式,提出相应保障措施,进而推动畜牧业实现绿色发展。  相似文献   
5.
l-proline (Pro) is a precursor of ornithine, which is converted into polyamines via ornithine decarboxylase (ODC). Polyamines plays a key role in the proliferation of intestinal epithelial cells. The study investigated the effect of Pro on polyamine metabolism and cell proliferation on porcine enterocytes in vivo and in vitro. Twenty-four Huanjiang mini-pigs were randomly assigned into 1 of 3 groups and fed a basal diet that contained 0.77% alanine (Ala, iso-nitrogenous control), 1% Pro or 1% Pro + 0.0167% α-difluoromethylornithine (DFMO) from d 15 to 70 of gestation. The fetal body weight and number of fetuses per litter were determined, and the small and large intestines were obtained on d 70 ± 1.78 of gestation. The in vitro study was performed in intestinal porcine epithelial (IPEC-J2) cells cultured in Dulbecco''s modified Eagle medium-high glucose (DMEM-H) containing 0 μmol/L Pro, 400 μmol/L Pro, or 400 μmol/L Pro + 10 mmol/L DFMO for 4 d. The results showed that maternal dietary supplementation with 1% Pro increased fetal weight; the protein and DNA concentrations of the fetal small intestine; and mRNA levels for potassium voltage-gated channel, shaker-related subfamily, member 1 (Kv1.1) in the fetal small and large intestines (P < 0.05). Supplementing Pro to either gilts or IPEC-J2 cells increased ODC protein abundances and polyamine concentrations in the fetal intestines and IPEC-J2 cells (P < 0.05). In comparison with the Pro group, the combined administration of Pro and DFMO reduced the expression of ODC protein and spermine concentration in the fetal intestine, as well as the concentrations of putrescine, spermidine and spermine in IPEC-J2 cells (P < 0.05). Meanwhile, the percentage of cells in the S-phase and the mRNA levels of proto-oncogenes c-fos and c-myc were increased in response to Pro supplementation, whereas depletion of cellular polyamines with DFMO increased tumor protein p53 (p53) mRNA levels (P < 0.05). Taken together, dietary supplementation with Pro improved fetal pig growth and intestinal epithelial cell proliferation via enhancing polyamine synthesis.  相似文献   
6.
非洲猪瘟在我国流行已有两年多的时间,尽管很多科研团队都在致力于非洲猪瘟疫苗的研发,但尚未有治疗措施和有效的疫苗来控制该病。因此现阶段“生物安全”是控制非洲猪瘟最为有效,也是唯一的方法。文章总结出目前规模化猪场常见的感染风险有“人员流动、物品流动、车辆流动、水源流动、猪群流动”(即“五流”),并提出严格控制“五流”的生物安全防控措施(即“五流”生物安全防控),以减少外界病原与猪只的接触,稀释病原浓度,降低病原载量,最大程度地降低规模化养猪场感染疾病的风险。为当前规模化猪场建立有效的生物安全措施提供参考。  相似文献   
7.
参与主体对于政策的评价是衡量政策实施效果的重要指标,探明政策参与主体满意度影响因素有助于了解主体自身需求,从而提高政策实施水平。文章基于对河北省380家生猪养殖主体调研数据,运用多元有序Logistic回归方法,分析生猪养殖主体自身政策认知以及相关政策执行力度对畜禽养殖主体废弃物资源化利用满意度的影响。结果表明:养殖主体资源化利用政策了解程度能够显著提升其资源化利用政策满意度;仅考虑养殖主体政策参与力度,随着参与力度增加,满意度亦会显著提升。但综合考虑其他因素,参与力度对于满意度提升效果则不再显著;养殖主体感知政策执行力度增加不利于政策满意度提升。此外,生猪养殖主体废弃物资源化利用政策了解程度增加,可以显著提升其报告资源化利用政策“满意”可能性。而单纯提高资源化利用政策执行力度并不能显著提高养殖主体资源化利用政策满意度。因此,要提高养殖主体政策满意度,应多渠道提升宣传力度,鼓励养殖主体积极参与,提高其参与意识,不断改善现有政策执行方式。  相似文献   
8.
随着“互联网+”时代的到来,数据挖掘、数据共享、云计算等信息技术为农机的智能化和信 息化管理提供有效方法和手段。为更好的推动农业经济发展,有必要借助先进的信息技术手段,搭建 一个基于“互联网+”的智慧农机管理信息数据共享平台,使我国农机管理进入大数据时代,推进智慧 农业发展。  相似文献   
9.
Asian shrimp farming industry has experienced massive production losses due to a disease caused by toxins of Vibrio bacteria, known as early mortality syndrome/acute hepatopancreatic necrosis disease (EMS/AHPND) for the last 5 years. The disease can cause up to 100% cumulative pond mortality within a week. The objective of this study was to identify factors associated with AHPND occurrence on shrimp farms. A case–control study was carried out on shrimp farms in four provinces of Thailand. Factors related to farm characteristics, farm management, pond and water preparation, feed management, post‐larvae (PL) shrimp and stock management were evaluated. Multivariable logistic regression analysis identified factors affecting AHPND occurrence at the pond level. Chlorine treatment, reservoir availability, use of predator fish in the water preparation, culture of multiple shrimp species in one farm and increased PL stocking density contributed to an increased risk of AHPND infection, while delayed first day of feeding, polyculture and water ageing were likely to promote outbreak protection. Additionally, the source of PL was found to be associated with AHPND occurrence in shrimp ponds, which requires further study at the hatchery level. Identification of these factors will facilitate the development of effective control strategies for AHPND on shrimp farms.  相似文献   
10.
北京郊区具备发展休闲型家庭农场的多种条件,可以通过理性规划,准确定位;注入农耕文化,融于体验;塑造品牌,注重营销的创新发展策略来展开。在此基础上,政府应通过加强引导,提供各种政策保障;调整发展思路,促进农场区域化发展;建立休闲型农场专门人才的培养机制,提升农场主文化与经营水平等一系列保障机制来实现。  相似文献   
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