排序方式: 共有81条查询结果,搜索用时 78 毫秒
31.
Systems Dynamic Digraph Analysis of Scale Pig Production Development in Center China 总被引:2,自引:0,他引:2
Cuixia Wang 《系统科学与信息学报》2006,4(4):811-824
Scale pig production is an effective approach to improve farmers' income. Many pig feeding villages and intensive pig farms has presented rapidly in Center China in recent years, the focus of large quantity of manure and sewage discharged by pig farms has become the leading source of pollution in vast rural areas. How to dissolve the contravention between the development of scale pig production and the serious pollution caused by swine excreta in rural area is a complex systematic problem. An approach named Systems Dynamic Digraph Analysis Approach is presented in this paper. And the approach is applied to analyze the scale pig breeding system in small hill watershed area systematically. A case of Pingxiang Taihua pig farm in the west region of Jinggang Mountain, which is a typical intensive pig farm in small hill watershed area in Center China, was studied, after the systematical analyses with its system dynamic digraph, three common management policies are presented at the end of the paper. 相似文献
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猪肺疫流行原因与对策 总被引:1,自引:0,他引:1
通过对部分地区暴发A型巴氏杆菌病的调查研究,分析得出此病流行的主要原因是气候急剧变化、环境恶劣、饲养管理水平低下、菌株血清型改变、滥用抗生素等。其流行特征是以急性型最多,以肺炎症状和败血症状为主,部分病畜康复后可再次感染。提出了防治此病的有效措施。 相似文献
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猪粪与生活垃圾混合堆肥的微生物数量变化研究 总被引:1,自引:0,他引:1
研究了猪粪与生活垃圾混合堆肥过程中的微生物如细菌、真菌、放线菌、大肠菌群等数量的变化.结果发现:所有微生物的数量都发生了变化,细菌、放线菌、真菌呈现高、低、稍高的变化,但已达不到堆肥开始时微生物的数量.大肠菌群数呈现高、低的变化,在堆肥后期没有检测到. 相似文献
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Erns is a highly glycosylated envelope protein of classical swine fever virus (CSFV) with RNase activity. Erns can induce neutralizing antibodies and provide immune protection against CSFV infection. In this study, the RNase domain of the Erns was produced in Escherichia coli. Its reactivity with CSFV-positive sera and its ability to induce antibodies and to provide protective immunity were then investigated. The serological tests showed that the prokaryotically expressed RNase domain of the Erns retained its antigenicity and induced high titers of humoral responses. However, only partial protection and a limited amount of neutralizing antibodies were demonstrated by an in vitro neutralization test and an immunization/challenge test. The results suggest that other essential factors rather than simply enhancing the immunogenicity of Erns should be taken into consideration when Erns is enrolled as one of the components of a candidate vaccine. 相似文献
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鸟粪石沉淀法用于养猪场污水前处理的影响因素研究 总被引:1,自引:0,他引:1
用鸟粪石沉淀法对养猪场污水进行前处理,研究了各类因素对沉淀效果的影响,包括加药剂与调节pH值的顺序、搅拌速率、温度、反应时间、溶液pH值与加入的药剂量等,其中溶液pH值与加入的药剂量是养猪场污水中污染物去除的决定性影响因素.本实验条件下,P/Mg/N比为1/1/1.2、pH10.0时,有最佳NH4+-N的去除率与最低PO43-P的残留浓度,分别是87%和30.21mg/L. 相似文献
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病毒性肝炎——值得警惕的重要人兽互传病 总被引:11,自引:0,他引:11
概述了人类病毒性肝炎的发病特点及流行状况、动物模型和自然感染病毒性肝炎的情况。简述了笔者的研究室在动物病毒性肝炎方面的研究进展。引起人类病毒性肝炎的病因复杂多样,病毒性肝炎严重地威胁着人类的健康。尤其是随着时间的推移,人类病毒性肝炎的发病率在不断提高,作为一种人兽互传病——病毒性肝炎已在动物中广泛存在,尤其是在畜禽中的分布,是我们不可回避的事实。人类病毒性肝炎的蔓延速度之所以如此之快,可能与动物有关,特别是与人类生活关系比较密切的家畜和家禽有关。动物病毒性肝炎的存在已对公共卫生造成显著影响,对人类健康构成严重威胁。建议相关主管部门重视对病毒性肝炎的研究工作,从公共卫生的角度组织研究动物,特别是畜禽病毒性肝炎与人的病毒性肝炎之间的关系问题,尤其是其间的传播问题,为防制此类疾病的进一步蔓延、流行,保证动物产品的卫生安全,保障人类的健康提供科学依据,并尽快采取防控措施。 相似文献
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兔脾淋组织液增强猪瘟细胞苗免疫抗体效价的试验 总被引:1,自引:0,他引:1
采用1%健康兔脾淋组织液稀释猪瘟细胞苗分别免疫10日龄经猪瘟乳前免疫的仔猪和经60~65日龄采用细胞苗二免的120日龄中猪,与生理盐水稀释组对照,免疫后15d采血检测抗体(IHA法)。二次试验结果表明:用兔脾淋组织液稀释猪瘟细胞苗免疫猪比用生理盐水稀释猪瘟细胞苗免疫猪可产生更高的保护性抗体效价,两者的差异均极显著(P<0.01)。 相似文献
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对5个典型的堆肥或施用猪粪尿的农田土壤重金属垂直分布进行了研究。结果显示猪粪的施用可以增加土壤中有机质的含量并使土壤pH值升高。且土壤深度的增加与pH值的升高表现为极显著正相关(p〈0.01)。施用猪粪土壤中Cd和Zn在不同深度土层中呈“峰”型分布.而Cu在不同深度土层中表现为上部富集。Cu,Zn,Cd在农田土壤系统下的迁移能力如下:Cd〉Zn〉Cu。重金属的迁移是个复杂的过程,不但与土壤pH值和有机质含量有关.而且还受其他因素控制。 相似文献
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