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A. Brandt‐Kjelsen E. Govasmark A. Haug B. Salbu 《Journal of animal physiology and animal nutrition》2014,98(3):547-558
Inorganic selenium (Se) in the form of selenite is applied to livestock to avoid Se deficiency. Selenite is, however, an artificial Se source in diets of unsupplemented chickens. It is therefore hypothesized that organic Se sources, such as Se‐enriched yeast and wheat, could be a more suitable Se supply in animal nutrition, although information on the transition of Se from organic Se sources in fast‐growing chickens is scarce. In this work, chickens were fed a low Se diet (0.27 ± 0.01 mg Se/kg, Se‐enriched yeast) until 20 days of age, after which the Se concentration was increased to maximum concentration allowed by the poultry industry in Europe (0.5 p.p.m. Se). At the same time, a daily contribution of carrier‐free 75Se tracer from labelled wheat was administered from day 20 to 27. The chickens showed S and Se homeostasis, as the concentration of S and Se in liver, blood or kidney remained about constant, and steady state of S and Se in the other organs was reached 1 day after the diet shift. The uptake of 75Se was readily seen in all organs. After 1 week, the depuration of the 75Se tracer was followed, and biological half‐lives and retention in individual organs were determined. The shortest biological half‐lives were observed in major metabolic organs, the liver, kidney and pancreas with half‐lives close to 4 days. There was a significant (p < 0.05) uptake in lung, brain and muscle that reached steady state when the administration of 75Se was terminated. The half‐life of 75Se in heart was 9 days and 7 days in blood. The longest half‐lives were observed in muscle (12 days), brain and lungs (13 days). All half‐lives were shorter than in Se deplete animals. 相似文献
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The distribution in the mouse of Se75 after injection of Se75 sodium selenite was studied by autoradiography of sagittal whole-body sections. The animals were killed at various times, from 5 minutes to 8 days, after a single intravenous injection.The distribution was characterized by a high blood level of selenium during the whole observation period.The highest concentration of selenium soon after the injection was found in the liver, heart, kidney and adrenal cortex. Eight days after the injection the highest concentration was seen in the liver and the kidney. The selenium penetrated the placenta, but the uptake was much lower in the fetuses than in the maternal tissue. 相似文献
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Platelet and fibrinogen survival times were determined in healthy pigs and in pigs infected with African swine fever (ASF) virus. Cohort labeling with [75Se]selenomethionine was performed. The platelet survival time in healthy pigs was 5.3 +/- 0.7 days, and the fibrinogen survival time was 6.7 +/- 0.8 days. Early deaths and profound thrombocytopenia prevented calculation of accurate platelet and fibrinogen survival times in ASF virus-infected animals. The ASF virus-infected pigs died of extensive hemorrhage and effusions while thrombocytopenic; however, there was normal thrombocytopoiesis during infection, as measured by incorporation of the radionuclide into platelets. There was a slight decrease in plasma fibrinogen concentration when the platelet count decreased. A dysfunctional fibrinogen was present late in the infection. 相似文献
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朴世俊先生生于1945年。获首尔大学微生物学院和高丽大学生命环境学院双硕士学位。曾任韩国发明新知识协会名誉会长、亚洲大学客座教授,现任韩国ENTECHBIO生物株式会社总经理。到目前为止,他已有世俊DO泵、食品垃圾资源化系统、水果糖度 相似文献
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微量元素硒的研究进展 总被引：8，自引：0，他引：8
近二十年来，科学家们开展了硒对动物体影响的研究，逐渐认识到了微量硒对生命过程的重要性。我国近来在硒与克山病关系的研究上已取得了举世瞩目的成果。在国外，科学家们在硒的研究方面同样取得了令人振奋的成绩。从最近的报道得知，体内有２８种硒蛋白，已经克隆并测定哺乳动物９种硒蛋白的ＤＮＡ序列，其它硒蛋白的结构和生物学功能将是今后研究的课题。１硒的生物学功能动物摄取硒的主要来源为食物，食入的硒通过肠道（十二指肠）吸收。吸收的硒首先进入血液，主要与血浆白蛋白结合，然后由血液转运到全身各个器官和组织。肝有贮蓄过量… 相似文献
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Evasion of phagocytosis is an important virulence determinant of Streptococcus equi (S. equi subsp. equi), the cause of equine strangles and distinguishes it from the closely related but much less virulent S. zooepidemicus (S. equi subsp. zooepidemicus). We describe Se18.9, a novel H factor binding protein secreted by S. equi but not by S. zooepidemicus that reduces deposition of C3 on the bacterial surface and significantly reduces the bactericidal activity of equine neutrophils suspended in normal serum for both S. equi and S. zooepidemicus. Se18.9 is secreted abundantly by actively dividing cells and is also bound to the bacterial surface. Strong serum and mucosal antibody responses are elicited in S. equi infected horses. Although a gene identical to se18.9 was not detected in S. zooepidemicus, sequences encoding proteins of similar size with similar signal peptide sequences were found in 3 of 12 randomly selected strains. Since Se18.9 is unique to S. equi, and immunoreactive with convalescent sera and mucosal IgA, it has potential for immunodiagnosis and for study of mucosal antibody response to S. equi. 相似文献
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分子生物学的研究揭示,微量元素通过与蛋白质和其它有机基团结合,形成酶、激素、维生素等生物大分子,"以微见著",发挥着重要的生理生化功能.微量元素不但构成了机体内重要的载体与电子传递系统,而且还参与激素与维生素的合成.酶是生命的催化剂,至今发现动物机体内有1000多种酶,其中约50%～70%需要微量元素参与或激活;微量元素对核酸的物理、化学物质均可产生影响,目前已确定一些金属离子在维持核酸的双螺旋结构与核蛋白方面有重要作用;微量元素如Zn、Cu、Mn、Se对免疫功能有重要影响.因此,微量元素是动物机体不可缺少的组成部分.针对我省大部分地区因Se等元素缺乏而给养殖业造成巨大的经济损失这一现状,本课题组研制出一种含铜、铁、锌、硒的牛复合微量元素缓释制剂,实验证明该制剂能降低奶牛微量元素缺乏性疾病的发病率,提高产奶量及乳品品质;同时,还能提高肉牛肥育率及生产性能等.为了能使该制剂在生产上大规模的推广应用,笔者等探讨了该制剂的安全性及相关因素,现报道如下. 相似文献
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微量元素硒的研究进展 总被引：11，自引：1，他引：11
1 硒的生物化学功能硒作为一种化学元素,一直被认为是一种对人畜有毒的物质。直到1957年,Ｓｃｈｗａｒｚ等发现从酿酒酵母中分离出的生物活性因子Ⅲ(即硒),能预防老鼠因ＶＥ缺乏而引起的肝坏死,才使人们认识到硒是动物体的必需微量元素之一。硒的生化功能是多方面的,其中最重要的是硒具有抗氧化作用,抗氧化作用的实现主要通过酶和非酶两个途径。谷胱甘肽过氧化物酶(ＧＳＨ—ＰＸ)是哺乳动物体内第一个被公认的含硒酶,于1957年由Ｍｉｌｌｓ和Ｒａｎｄａｌｌ首先发现,但直到1971年才由Ｒｏｔｒｕｃｋ的研究证明了硒是ＧＳＨ—ＰＸ的组成物质… 相似文献
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