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反刍动物消化营养研究中常用指示剂的特性与应用 总被引：1，自引：0，他引：1
对反刍动物消化营养研究中常用指示剂的特性、应用范围和利弊进行了分析和综述，为今后研究中指示剂的选择和应用提供理论参考。 相似文献
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反刍动物消化营养研究中的指示剂 总被引：2，自引：0，他引：2
在反刍动物消化营养研究中，很难利用全部收集营养物质的方法来测定养分的消化率或某段消化道内食糜的流通量。而应用指示剂与消化前后营养物质间比例关系的变化，可以计算出所需要的试验数据。在反刍动物消化营养研究中应用的指示剂，一般分为内源指示剂和外源指示剂。但不论哪一种，作为理想的指示剂都应该符合以下条件：１）无任何毒副作用；２）在动物胃肠道中绝对不能被消化和吸收；３）不结块，与食糜混合均匀，并保持其分布不变；４）对胃肠道的分泌、消化、吸收等正常生理功能和微生物区系无影响；５）从物理特性来看，与所标记的物… 相似文献
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指示剂法和套算法计算饲料养分消化率公式的推导和应用 总被引：3，自引：0，他引：3
饲料养分（包括总能）消化能的测定和计算是饲料营养价值评定的基础工作。测定饲料养分消化率的体内消化试验法有全收粪法和指示剂法。如果进行一次试验即可测出饲料养分的消化率，则称这种测定方法为直接法。但对不能或不宜单一饲喂的饲料，其养分消化率的测定需要采用间接法（或套算法)。已有文献中对指示剂法和套算法计算饲料养分消化率的公式缺乏推导。本文拟对指示剂法和套算法计算饲料养分消化率的公式进行推导，以便正确运用这些公式进行饲料养分消化率的计算。1指示剂法计算饲料养分消化率公式的推导及应用指示剂法是利用动物消化道… 相似文献
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在应用GB6436—86附录B“乙二胺四乙酸二钠络合滴定快速测钙”法（补充件）测定饲料中钙含量过程中，常常出现钙红指示剂在等量点附近无敏锐颜色变化，甚至无颜色变化的现象。这是由于饲料中特别是在添加了预混料的配合饲料中，以及磷酸氢钙、骨粉等饲料添加剂中，常含有Fe~(3 )、AI~(3 )、Co~(2 )、Ni~(2 )、Cu~(2 )、Hg~(2 )等离子，这些离子能与钙红指示剂形成十分稳定的红色配合物，不能被EDTA破坏或被破坏的速度很慢，因而产生了指示剂的僵化、封闭现象，影响了该法测定钙的准确度和精密度。经我们试验研究，可在测定过程中加入… 相似文献
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精确计算牧场生产力和放牧期间的日粮平衡,测定家畜的实际采食量便具有很大的意义,为了解决这一问题,曾研究了采用两种指示剂—外指示剂(通常是Cr_2O_3)和内指示剂的方法。外指示剂是通过补料补饲给家畜的,用于定量测定排出的粪便。内指示剂是借助于一种含在饲料中的消化率很低的物质,可测知牧草的干物质和有机物质的消化率来估测家畜的采 相似文献
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ＥＤＴＡ法测定饲料中钙的过程中指示剂的僵化封闭现象及其消除王新平（广东佛山农牧高等专科学校基础部５２８２３１）前言在应用ＧＢ６４３６－８６附录Ｂ“乙二胺四乙酸二钠络合滴定快速测钙”法（补充件）测定饲料中钙含量过程中，常常出现钙红指示剂在等量点附近无敏... 相似文献
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饲料级硫酸锌中锌、镁的连续测定 总被引：2，自引：0，他引：2
本实验研究了饲料级硫酸锌中锌和镁含量的连续配位滴定方法,在pH=5～6的缓冲溶液中,以二甲酚橙作指示剂,EDTA滴定锌;然后调节pH=10,并加入缓冲溶液,以铬黑T作指示剂,用EDTA连续滴定镁：测定结果准确、可靠,且方法具有操作简便、快速等优点。 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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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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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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