饲料中无机元素分析方法研究进展

饲料中所含的无机元素对动物生长具有重要意义。在饲料中过量添加无机元素会导致环境污染问题,也会通过食物链最终危害消费者的身体健康,因此,对饲料产品中的无机元素进行检测和动态监控尤为重要。综述了近年来饲料中无机元素含量检测主要应用的前处理方法及其含量检测技术,分析了不同前处理方法和含量检测技术的优点和不足,以期为饲料中无机元素分析方法的科学、合理应用提供参考。     

规模化畜牧养殖对生态环境的破坏及防治

近年,畜牧养殖业蓬勃发展,过去的区域化散养已经基本不存在,养殖结构逐渐向集约化、一体化、规模化过渡,养殖规模也逐渐增大。养殖副产品肉、蛋、奶等极大满足了人们的生产生活,养殖中产生的尿液、粪污对生态环境造成极大影响。为促进规模化养殖实现绿色健康发展,该文分析规模化畜牧养殖对生态环境的破坏及防治措施。     

城镇化水平计算方法比较分析

城镇化是社会经济发展的必然趋势，与小城镇人口、经济实力、社会发展和环境保护等方面密切相关。城镇化判别指标归纳起来分两大类：一类是单一指标法或称主要指标法；另一类是多项指标法、复合指标法或称综合指标法。在常用的、单一指标法的城镇化水平计算方法中，城镇人口比重指标法和带眷系数法两种方法能够比较准确地反映小城镇的城镇化水平，尤其以城镇人口比重指标法计算结果最符合实际。     

湟源县草地资源基本特点及开发利用

湟源县草地面积有 85 1 85 .1 3hm2 ,占全县土地总面积的 5 6.45 % ,草地资源丰富 ,牧草种类较多 ,农业生产秸秆来源广泛 ,但由于利用不当 ,造成了草地严重破坏和秸秆的浪费 ,如何合理利用草地和秸秆资源 ,扼制草地退化 ,是促进该县畜牧业发展的重要因素     

四川省退耕还林模式初探

根据自然地理分异规律、社会经济技术原理、生态学原理,分析了四川省的水土流失概况,提出了川中丘陵、盆周山地区、川西南干热干旱河谷区、川西北高山高原区的退耕还林模式。     

果树技术经济效益评价的程序与方法研究

本文结合果树生产实际,阐述了果树生产技术经济效益评价研究的基本方法、基本程序步骤和各步骤实施的要求,对评价结果的分析方法进行了较为详细的说明。其中包括对比分析法、试算分析法、边际分析法在果树生产技术经济效益评价研究上的应用。同时本文对该课题中所涉及的几个果树技术的经济效益评价方法程序进行了各论。     

Genetic Engineering Approaches to Pig Production*

Modern biotechnology promises a number of new applications in animal breeding and production. Although conventional pig breeding has achieved a high level of efficiency and productivity numerous problems have been encountered with animal health and the loss of meat quality. Selection based on phenotypic performance data of individual animals does not take into account the importance of specific genes and their relevance within a complex regulatory system. In most cases it is therefore difficult to trace back the genetic origins of clinically important disorders. The application of genetic engineering techniques in pig production will facilitate diagnosis, improvement of productivity, and animal health by allowing direct genetic manipulation. Attention must be focussed on the physical and genetic analysis of the procine genome. The isolation and characterisation of genes, DNA-markers, polymorphic DNA-fragments, and their chromosomal assignment will be important prerequisites and tools for the elucidation of genetic disorders. Especially the detection of heterozygous carriers of recessive disorders and their elimination from the breeding stock will increase selection accuracy and decrease the generation intervals. But also the rapid and simple detection of infectious diseases, which is sometimes difficult if not impossible at present, will improve animal health and welfare. Although the production of transgenic animals either by DNA-microinjection into zygotes or the use of embryonal stem cells manipulated in vitro is less straightforward than DNA-based diagnosis it will play an important role in the direct manipulation of the porcine genome and genes. Breeding programmes including the use of transgenic livestock have already been developed. There is no doubt that genetic engineering has reached a degree of practical feasibility, allowing it to play an important role in pig breeding in particular and animal production in general.     

一类正规矩阵的反问题

In this paper, we consider the inverse problems for a kinds of normal matrices. Some necessary and sufficient conditions for existence of solution of these problems are given. The expression of the general solution is given.     

耕牛血吸虫病检测方法比较试验

目的为了解几种检测耕牛血吸虫病的敏感性进行本试验。方法将经粪便毛蚴孵化法检出血吸虫病阳性的水牛(6头)，同时进行干卵聚酯薄膜环卵沉淀试验、间接血凝试验及快速诊断试纸盒检验的测试。结果以其检测结果与粪便毛蚴孵化法相比，阳性符合率分别为100％、100％和83％，3种方法间无显著差异。结论快速诊断试纸盒检测法以其操作简便且准确、快速、特异性高的特点，在动物血防普查工作中具有广阔的应用前景。     

提高农用潜水电泵修复可靠性的方法

对以QY系列为主体的农用潜水电泵修复可靠性低、寿命短的问题，提出了改进措施，从而有效提高潜水电泵修复可靠性，并延长使用寿命。