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我们知道．一定的社会系统中．可供人类自由调配的资源大致可分为物质资源、人力资源、文化资源。在这三大资源中,物质资源是“死物”,人力和文化资源是“活物”．三者虽互为因果．但由于文化资源决定着人们的价值取向或思路．因而决定着物质资源和人力资源的分配能否产生最佳的经济效应。 相似文献
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生物发酵床养猪法——对“生物发酵床”养猪的了解 总被引：1，自引：0，他引：1
随着养猪规模化、集约化程度的不断提高,我国养猪业当前面临着三大难题：一是质量安全,二是效益提高,三是环境治理。由这三大问题直接表现出来的药物残留、能源缺乏、饲料短缺、疫病频繁、环境污染等已成为限制我国养猪业发展的瓶颈因素。 相似文献
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曹阳昭 《四川畜牧兽医学院学报》2012,(2):41-44
协调我国区域法制冲突是完善我国区域法制建设的基本需求,也是促进我国区域经济一体化发展的必由之路。由于复杂的经济、历史和政治因素,我国目前存在着中央与地方冲突、区域平行冲突和法域冲突这三大类型的区域法制冲突。通过制定区域法制冲突协调规范,建立起一套以区域平等协商、自由合作为基础的区域法制冲突的协调机制,是解决我国区域法制冲突最行之有效的方法。 相似文献
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断奶仔猪是承接猪只生长速度慢到生长速度快的阶段,但它们要承受心理、营养和环境三大应激。在这三大应激下,断奶仔猪最容易发生的疾病就是断奶后下痢。此病在我国各种规模的猪场,以及养殖专业户均有不同程度的存在，是造成仔猪死亡和影响仔猪生长发育的主要原因之一, 相似文献
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１畜牧产业化势在必行畜牧业是我国国民经济的重要行业和支柱产业之一，应该是产加销衔接紧密的一个整体，具有相对完整的产业链。在市场经济条件下，从畜牧业内部来看，当前存在着三大矛盾。一是千家万户的小生产与千变万化的大市场之间的矛盾。分散经营由于存在着生产选... 相似文献
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免疫──神经──内分泌系统间的关系 总被引：1，自引：0，他引：1
机体各器官的机能活动主要由神经、内分泌和免疫系统来调节，这三个系统间存在着复杂而密切的相互关系，共同维持着生物体的正常生命状态。本文就上述三个系统间的相互关系作以简要综述。 相似文献
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Mammalian parental investment (i.e. care of descendant offspring) is largely biased towards maternal contributions due to the specific feeding needs of mammalian offspring; however, varying degrees of paternal investment have been reported in about 10% of all mammalian species. Within the order Carnivora, paternal contribution to rearing offspring is particularly high: an estimated 32% of all studied carnivore species exhibit direct paternal care. Despite the prominence of paternal investment in carnivores, the endocrine basis of this behaviour is not well understood. This review examines the current – highly constrained – state of knowledge about the endocrine basis of carnivore paternal investment. We attempt to link changes in androgen and glucocorticoid levels with variation in direct and indirect paternal care behaviour making specific predictions regarding the way forward. Well-studied species, such as bat-eared foxes (Otocyon megalotis), dwarf mongoose (Helogale parvula) and meerkats (Suricata suricatta), where social dynamics are relatively well understood, can act as ideal model systems through which we may further investigate the endocrine basis of paternal investment in carnivores. 相似文献
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牛磺酸在动物内分泌系统中的生理作用 总被引：1，自引：0，他引：1
牛磺酸是一种含硫条件性必需氨基酸,对机体生长发育、繁殖、免疫机能等有重要的营养和生理作用。研究表明,机体缺乏牛磺酸时,内分泌系统功能发生障碍,导致各种内分泌疾病发病率上升,包括甲状腺功能亢进、生殖功能退化、糖尿病、肾脏疾病等内分泌疾病,阻碍机体正常的生长与发育,严重影响畜牧养殖业。近年来,关于牛磺酸对内分泌系统作用的研究并不多,临床上的应用上更不多见。论文对牛磺酸在下丘脑-垂体、甲状腺、肾上腺、性腺、胰岛等器官的内分泌作用进行综述,为牛磺酸在畜牧生产中的应用提供参考。 相似文献
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The intake of colostrum in newborn calves not only influences the immune status, but also the development of the gastrointestinal tract and other organs, metabolism and endocrine systems. Besides nutrients bioactive substances of colostrum have additionally to be considered. Metabolic and endocrine effects are transient, indications for metabolic and endocrine imprinting by differences in feeding in the first week of life have so far not been found. Nevertheless, changes observed in association with feeding especially of colostrum are considered important for the critical first week of life. 相似文献
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草地放牧系统优化模型的研究进展 总被引：3，自引：2，他引：1
生态学研究的定量化发展,以及环境资源管理的迫切需求,伴随着计算机的广泛使用,生态模型作为生态系统研究的重要工具,从19世纪20年代至今发展十分迅速,在生态系统研究的各个领域都有很好的应用。草地放牧系统作为生态系统重要组成部分,对其研究自然也离不开模型的应用。本研究对草地放牧系统优化模型的研究进行了评述。具体阐述了以下几个方面:1)草地放牧系统的概念以及与草地生态系统的区别与联系;2)基于环境资源的不断恶化以及生产实践的迫切要求讨论了草地放牧系统优化的意义;3)从植物生产亚系统、动物生产亚系统、管理亚系统3个方面阐述草地放牧系统优化模型的研究进展,以及其中存在的问题;4)主要集中在模型目标、技术手段和实证问题几个方面对于草地放牧系统的发展方向进行了展望。 相似文献
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U Magnusson 《Reproduction in domestic animals = Zuchthygiene》2012,47(Z4):333-337
In this review, possible comparative advantages of studying endocrine disruption in farm animals vs laboratory rodents are discussed. First, using farm animals, the generality of findings in laboratory rodents are challenged. Farm animals may in certain aspects be better models for humans than laboratory rodents, and sometimes there might be methodological advantages in using farm animals. Second, there are several in vitro studies based on cell-culture systems from sows and cows where the effects of chemicals on sex steroid secretion can be measured and maturation and fertilization of oocytes may be assessed. These in vitro systems are powerful tools for dissecting the mechanisms of action for endocrine-disrupting chemicals. Third, in a set of recent in vivo studies using sheep, goats and pigs, in which very different exposure regimens to endocrine-disrupting chemicals have been used, a full panel of reproductive parameters pertinent to farm animals were assessed. Clinically, it is suggested that endocrine disruption in farm animals should be considered when impaired reproduction could be linked to change in source of feed or pasture. Finally, epigenetic and toxicogenomic approaches can be particularly rewarding in elucidating endocrine disruption in future farm animal studies. 相似文献
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反刍动物胃肠道中存在着众多微生物,如细菌、真菌、原虫和古细菌等。胃肠道微生物对于动物的能量代谢发挥着重要作用,同时对于动物的中枢神经正常功能的发挥也扮演着重要角色。肠道微生物可以与肠道细胞直接接触,不仅产生激活内源性中枢神经系统信号传导机制的代谢物,还可以独立地产生或促成许多神经活性分子的产生。微生物代谢产物和神经活性分子通过神经信号通路、胃肠道内分泌信号通路、免疫系统等关键途径共同形成一个复杂的反射网络,即胃肠道微生物与代谢产物通过传入神经元将信号传导至中枢神经系统。胃肠道微生物与宿主之间通过主要的信号通路相互作用,影响机体胃肠道屏障、营养代谢、免疫应答等生理机能和摄食行为。作者主要从反刍动物胃肠道微生物的种类、微生物通过肠道-脑轴的"自下而上"的传导途径、微生物及其代谢产物通过肠道-脑轴对宿主疾病和行为起到的作用、胃肠道微生物-肠道-脑轴可能的影响因素进行浅析,并对反刍动物胃肠道微生物-肠道-脑轴的研究进行了展望。 相似文献
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This paper evaluates the association between herd level risk factors for introduction and transmission of Salmonella in farms with three different production systems: organic, outdoor (non-organic) and indoor finishing-pig farms, and the presence of seropositive animals in the herds. Potential risk factors for Salmonella in the three pig production systems were identified through a literature review, and management information as well as serological data were collected in 34 pig farms: 11 organic farms, 12 outdoor farms, and 11 indoor farms. There were no general differences in the proportion of Salmonella seropositive animals in the organic, outdoor, and indoor pig farms. Correspondence analysis showed that the occurrence of seropositive animals in the herds was mostly associated to the risk of introducing Salmonella in the herds by purchasing and transporting growing pigs. No associations between herd risk factors for transmission and survival of Salmonella and seropositive animals in the herds were found. 相似文献
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A large body of information proves that Orexin-A is present in the pancreatic endocrine cells of humans and laboratory animals; more detailed studies identify Orexin-A-immunopositive cells as beta cells. Because no data have been reported on the pancreas of domestic animals, we investigated the presence and the distribution of cells containing Orexin-A in the pancreas of cattle, sheep and pigs by means of immunohistochemical techniques.Using a polyclonal antibody against Orexin-A, the immunopositive reaction was identified in the cytoplasm of many insular cells in the three species studied.Double immunohistochemical staining, using a polyclonal anti-insulin antibody, showed that Orexin-A is co-expressed with insulin.Our results, besides showing the presence of Orexin-A in the endocrine pancreas of domestic animals, together with data present in the literature, could contribute to the understanding of complex mechanisms regulating the functionality of the endocrine pancreas in domestic animals. 相似文献