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饲料中能量、氨基酸、脂肪酸、微量元素和维生素等营养成分在消化、吸收、代谢上存在各种互作关系,所以饲料配方不仅要满足动物对各种营养成分的单一需要,而且要通过平衡各营养成分之间的比例,达到营养全价、平衡。例如,日粮中能量水平和粗蛋白含量之间存在一个最佳的比例范围,高能量低蛋白和低能量高蛋白饲料都必然降低饲料转化效率,影响家禽生产性能的发挥。本文试图在动物营养中引入维生素平衡的概念,介绍维生素平衡的表现形式和破坏维生素平衡的因素,分析在动物生产中维生素应用的常见误区并提出相应的解决办法。 相似文献
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维生素是一组化学结构不同的有机化学物。它是动物机体生化反应和新陈代谢的催化剂,是维持动物正常机能和保持动物正常生长发育不可缺少的一种微量营养物质。除少数几种维生素可以在动物体内合成外,多数维生素都必须从饲料中摄取。由于有些饲料中的维生素含量达不到动物体的要求量,需要在饲料中添加各种维生素,以补充动物体代谢之要求。但是维生素的需要量随畜禽品种、生长阶段、饲养方式、环境因素的不同而不同。为此根据不同畜禽的需要量适量应用维生素添加剂, 相似文献
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饲料添加剂在饲料中占有举足轻重的地位,它包括氨基酸、维生素、微量元素、防病促生长素、饲料防腐抗氧化增效剂等。维生素是其中很重要的组成部分,在促进动物体生长,提高其生产力,维护动物体健康中起着必要的作用,它作为具有生物活性的生物化学物质,在生物体内起着催化作用,促进营养素的合成与降解,从而控制着机体的代谢。由于饲料原料所含天然维生素远远不能满足现代养殖业中动物体生长、生产的需要,而必须在配合料加工中加入工业化生产的维生素进行强化,以满足动物营养需要。但维生素对它所处的物理、化学环境相当敏感。因此对… 相似文献
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编者按:随着饲料工业的迅速发展,饲料添加剂日益成为畜禽日粮中不可缺少的成分,包括抗生素、维生素、微量元素、酶制剂、合成氨基酸、微生态制剂等,在保障畜禽健康、调节营养代谢、促进养分利用和改善饲料品质等方面发挥重要的作用。饲料添加剂最终作用是提高动物生产性能、 相似文献
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微量元素是动物生产中不可缺少的营养成分之一。它们在动物体内广泛地参与物质代谢的调控,以及酶、维生素和激素的形成及激活作用。论文综述了不同来源微量元素铜、铁、锰、锌在猪体内的吸收,存留和排泄以及对猪生长繁殖的影响。 相似文献
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不同来源微量元素对猪生长性能影响的研究进展 总被引:1,自引:0,他引:1
微量元素是动物生产中不可缺少的营养成分之一.它们在动物体内广泛地参与物质代谢的调控,以及酶、维生素和激素的形成及激活作用.论文综述了不同来源微量元素铜、铁、锰、锌在猪体内的吸收,存留和排泄以及对猪生长繁殖的影响. 相似文献
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饲料添加剂的概念起始于20世纪初期,基于动物营养理论和饲养研究发现,在饲料中添加少量的维生素和矿物质能够有效提高动物的采食量,提高饲料利用率,促进动物健康生长。近几年,随着生物技术的快速发展,饲料添加剂不再局限于微量营养素,逐渐扩展到酶制剂、生物添加剂、功能性寡糖、生物活性肽、核苷酸、甜菜碱、有机微量元素等新型饲料添加剂,这为饲料的配制研发提供了更多选择。 相似文献
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Beran GW 《Preventive veterinary medicine》2008,86(3-4):198-207
When early people made their appearance, zoonotic infectious diseases were already waiting, but epidemic diseases did not appear in human history until people began to live in large numbers under conditions of close contact, mainly during the last 10,000 years. Disease has decimated urban populations, conquered armies, and disrupted society. The focus here is on (1) the plague of Athens and the Black Death; (2) smallpox, influenza, and rabies; (3) avian influenza prion diseases, and foot & mouth disease; and (4) emerging and re-emerging diseases. All have veterinary public health associations. In Athens, Greece, in 430 BC, when the Spartans ravaged the countryside, hordes crowded into Athens so that orderly movements, space in which to live, and adequate supplies of food became impossible. Crowding of any population fosters disease transmission; chaos and disorder enhance it all the more. Out of northern Egypt came a terrible plague from across the Mediterranean Sea. The identity of the plague of Athens remains unsure, but the well-considered conclusion is Rift Valley Fever, a mosquito borne, viral zoonosis. The Black Death, also called the Plague, raged in Asia for centuries. In 1347, the Black Death was brought by a ship out of Asia to Sicily. The scenes of devastation were repeated throughout Europe, with 90% or more of the people dying in city after city. Influenza, too, has been a cause of periodic human epidemics, but the great pandemic of influenza occurred in the last months of World War I. In the years of highest occurrence, more than half the world's population became clinically infected. If veterinary public health had been born earlier, it could have led to elucidating the epidemiology of influenza and the plagues of Athens, Europe, and Asia. In turn, smallpox had also caused continual tragedy. In 1796, Edward Jenner began to harvest pustules of cowpox from children or infected cows and inject them into susceptible children. In 1980, the World Health Organization declared that smallpox had been eliminated from the world. Rabies, though, still strikes terror. A number of animal diseases, broadly termed emerging and re-emerging diseases, need surveillance because they have the potential to impact human health. From late in 2003 to 2007, the highly pathogenic H5N1 influenza virus in poultry infected at least 121 people and caused 62 deaths in four countries. The prion diseases, too, all have very high numbers in concentrated contacts. To control these diseases, veterinary public health is essential, with diagnosis, epidemiological surveillance, clinical manifestations, and prevention as primary measures. 相似文献
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在动物的异常行为中以刻板行为最为常见,而咽气癖又是马最常见的口部刻板行为之一。作者就咽气癖在生理方面和心智方面对马体产生的影响、行为基础、诱因的研究进展及常见的防治措施进行综述。 相似文献
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Dekker A Dercksen D Snoep J van Wuyjckhuise L 《Tijdschrift voor diergeneeskunde》2007,132(18):695-701
On 26th of july 2007 a new case of bluetongue was notified in the Netherlands and on 2nd of august 2007 foot-and-mouth disease was diagnosed in Surrey, England, which raised the threat of having both infections simultaniously in one area. Bluetongue and foot-and-mouth disease have a different pathogenesis, but symptoms may resemble each other at a later stage of infection. The pathogenesis and possible clinical symptoms of both infections are discussed and illustrated with pictures. 相似文献
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