钼对小鼠免疫功能的影响

钼（Mo）是动物、植物、微生物及人类必需的微量元素，是黄嘌呤氧化酶，醛氧化酶，亚硫酸氧化酶的组成成分，参与电子传递及铁的释放与运输，影响多种物质的代谢，具有重要的生理学功能。但过量的钼可导致动物中毒，并以反刍动物最为敏感。1938年Ferguson首次报道了牧草中钼含量过高，可使放牧牛产生以剧烈腹泻为特征的中毒性疾病。目前，有关钼对动物免疫功能的影响研究较少。本试验通过对小鼠日常饮水中加入不同剂量的钼，研究钼对小鼠免疫功能的影响，为动物钼中毒防治及科学饲养提供资料。     

钼对鸡的营养作用

自Ferguson(1938)在英国首次发现耕牛的钼中毒病后,人们一直认为钼是一种有毒元素,直到1953年Richert发现钼是大鼠黄嘌呤氧化酶的必需成分后,才肯定了钼对动物的必需性。几十年来,确关钼对鸡营养作用的研究很少,主要是由于①目前还没有理想的测定微量钼的方法②自然界中鸡的     

微量元素钼和反刍家畜

一、钼的重要性在动物和植物的新陈代谢中,有3种不可缺少的酶——黄嘌呤氧化酶、醛氧化酶和亚硫酸氧化酶。现已查明,在这3种酶的作用过程中,微量元素钼(mo)是必需的。自然界中,至今未见动物缺乏钼的报道。鸡和大白鼠的饲料中含有0.2ppm钼,未发现任何障碍。反刍家畜钼的需要量为0.1ppm(Anke等,1985)。饲草(茎叶饲料)中钼的含量极低(低于0.3ppm)。在挪威,认为发生铜中毒与钼的含量不足有关。     

钼对鸡的营养作用

自 Ferguson(1938)在英国首次发现耕牛的钼中毒病后,人们一直认为钼是一种有毒元素,直到1953年 Richert 发现钼是大鼠黄嘌呤氧化酶的必需成分后,才肯定了钼对动物的必需性。几十年来,有关钼对鸡的营养作用的研究并不很多,主要是由于①目前还未研究出理想的测定微量钼的方法;②在自然界中鸡的钼缺乏症很少发生;③缺钼所造成的影响只是逐渐地、缓慢地在畜禽生产中表现出来。目前,在我国东北、华东、四川省等地已发现土壤严重缺钼,农作物也因此严重减产,但采食缺钼地区粮食的人及动物是否存在着缺钼现象,还鲜有人报道。本文对近几     

家畜钼营养研究进展

自从Ferguson(1938)报道了高钼饲料与反刍动物(腹泻病)的关系以后,Richert等(1953)又发现了钼作为黄嘌呤氧化酶和醛氧化酶的成分是一种必需的营养因子,同时还发现钼是亚硫酸盐氧化酶的成分,也是瘤胃微生物的促进剂。随后,相继有人报道了反刍动物钼中毒,鸡和火鸡的钼缺乏症。我国也于1981年首次报道了耕牛的钼中毒,并已开始了这方面的研究。在人的营养方面,国内已有不少报道。本文对近十年来有关钼营养研究所取得的进展作一简要综述。一、钼的生物学作用 1.钼的主要生化功能是形成三种重要的酶:黄嘌呤氧化酶、醛氧化酶和亚硫酸盐氧化     

牛钼中毒的诊治

正钼是动物体内必需的一种微量元素,是黄嘌呤氧化酶、醛氧化酶、硫酸还原酶等多种酶的组成部分,在新陈代谢中起着重要作用。自然发生的钼中毒是由于采食含钼饲料所引起的继发性低铜症,又称继发性或条件性铜缺乏,其特征是顽固性腹泻、被毛褪色、皮肤发红、骨营养不良及进行性消瘦。钼中     

钼对山羊与绵羊的毒性比较

我国自1981年报道赣南大余县耕牛钼中毒事件以来，动物钼中毒病常有发生，但钼对羊特别是杂交波尔山羊的影响报道较少。为此，本试验应用不同剂量的钼给小尾寒羊、杂交波尔山羊灌服，观察其钼中毒时的临床表现以及其血液学指标和病理学变化的影响，为羊钼中毒的防治提供参考依据。     

微量元素钼对反刍动物营养代谢的影响

在生产实际中铁、锰、铜、锌、钴、氟、碘、硒等必需微量元素均有相应的盐类作为添加剂加到动物饲料当中 ,而钼则很少加入 ,这主要是因为大多数饲料原料中钼的供给量足可以满足动物的生长需要 ,但饲料原料中钼含量受土壤、大气、水源中钼元素的影响较大 ,当原料中钼含量较低不足以满足动物需要时 ,即可引发动物的钼缺乏病 ,这对反刍动物的影响尤为明显。反之 ,当钼过于富集时 ,尤其是农业生产中钼酸铵作为肥料的大量施用 ,使饲料原料中钼元素含量过高 ,又可引发钼中毒。1　钼的生物学功能钼元素 (Ｍｏｌｙｂｄｅｎｕｍ)自 1782年由Ｈｉｅｌ…     

钼与家畜营养

一、钼在家畜营养中的意义 钼在动物体内的生物化学机制除与铜反应外,它和黄嘌岭氧化酶、醛氧化酶以及亚硫酸盐氧化酶的形成与所具有的特异活性相关。钼还参与嘌呤氧化酶同细胞色素C的反应,促进被醛氧化酶催化的细胞色素C的还原。在动物体组织中,这种酶的浓度与采食日粮中钼的含量有关。     

微量元素钼在畜禽日粮中的应用

钼（Mo）首先是作为一种有毒的元素被人们所认识，钼中毒可使羊产生剧烈的腹泻和被毛褪色，被称为“Teart”病，因此，人们更多地把它作为有毒物质来进行防治中毒性疾病的研究。事实上，少量适宜的钼元素，是动物体内不可缺少的，对动物的生长、发育和遗传都起着重要的作用。     

商会自治的基石——商会自治规范研究

在现代法律秩序中,商会自治规范是制定法的基础和必要的补充,甚至在某些方面替代了制定法;商会自治规范主要包括商会组织规范、行为规范、惩罚规范以及争端解决规范等;其效力仅及于其内部成员;商会自治规范和制定法之间存在冲突,但也存在整合的基础。     

癸氧喹酯干混悬剂含量测定的改进

采用高效液相色谱法测定癸氧喹酯干混悬剂的含量,在2-250μg/mL范围内,峰面积的常用对数与进样量浓度的常用对数呈良好的线性关系,R^2=1(n=5),平均回收率为99.24%~99.51%,RSD在0.05%~0.28%。此方法分析时间短,样品前处理简便、定量结果准确,重现性好,结果满意,为其质量控制提供了依据。     

猪毛色遗传的研究进展

本文概述了猪的毛色类型、猪的毛色遗传模式,着重综述了猪毛色基因分子基础的研究进展,指出存在问题并就未来发展方向做了思考。     

Comparison of 2 methods of centesis of the bursa of the biceps brachii tendon of horses

REASONS FOR PERFORMING STUDY: Centesis of the bicipital bursa using an 8.9 cm long spinal needle has been reported but the alternative of employing a 3.8 cm long hypodermic needle requires validation. OBJECTIVE: To compare the efficacy of 2 different methods of centesis of the bicipital bursa and to evaluate the usefulness of ultrasonographic imaging to determine the location of solution administered when centesis of the bursa is attempted. METHODS: For Trial 1, 6 clinicians, who had no previous experience of centesis of the bicipital bursa, attempted to inject a solution composed of an aqueous radiopaque contrast medium and physiological saline solution (PSS) into the bicipital bursae of 2/12 horses using the previously described distal approach to inject one bursa and a proximal approach to inject the contralateral bursa. The bicipital tendon and bursa were examined ultrasonographically before and after injection; and both shoulders were examined radiographically to identify the location of the medium. In Trial 2, another 6 clinicians, also with no previous experience of centesis, repeated Trial 1, using 6 horses, but the radiopaque contrast medium was mixed with air instead of PSS. RESULTS: Accuracy of centesis using the proximal approach was 39% and that of the distal approach 28%. Ultrasonographic examination of the shoulder allowed the location of solution and air to be accurately predicted in all 12 shoulders examined. CONCLUSIONS: Clinicians who have had no previous experience performing centesis of the bicipital bursa are unlikely to be successful in centesis using either approach. Radiographic examination after injecting a radiopaque contrast medium may be necessary to assess the success of centesis especially if bursal fluid is not obtained during centesis. Injecting air along with the radiopaque contrast medium provides more accurate ultrasonographic confirmation of centesis and better radiographic definition than does injection without air.     

不同样本商品蜂蜜中硒含量的测定

用硝酸和高氯酸消化蜂蜜,使硒游离出来,在微酸性环境下,硒和2,3-二氨基萘(DAN)生成有较强荧光的物质,用环己烷萃取,在激发波长378nm,荧光波长518nm处测定其荧光强度。蜂蜜中硒含量范围:0.10～0.82μg/g。表明:蜂蜜应视为天然富硒营养品。     

乳酸杆菌益生作用机制的研究进展

乳酸杆菌作为益生菌广泛用于人和动物。本文综述了乳酸杆菌改善宿主健康的机制。乳酸杆菌可通过产生抗菌物质如乳酸、过氧化氢、细菌素,或者通过竞争营养或肠道黏附位点来抑制致病菌;通过诱导黏附素的分泌或阻止细胞凋亡而增强肠道的屏障功能,从而保护肠道。文章重点讨论了乳酸杆菌表面成分（表面蛋白、脂磷壁酸和肽聚糖）与肠道受体（Ｃ型凝集素受体、Ｔｏｌｌ样受体和 Ｎｏｄ样受体）,阐述了他们结合后启动免疫调节信号,调控肠道免疫功能以发挥改善健康作用的机制。     

Effects of size of ingestively masticated fragments of plant tissues on kinetics of digestion of NDF

Ingestively masticated fragments were collected and sized via sieving. Different sizes of esophageal masticate and ruminal digesta fragments, and ground fragments of larger masticated pieces were incubated in vitro, and undigested NDF remaining at intervals of up to 168 h of incubation was determined. The ruminal age-dependent time delay (tau) for onset of digestion of NDF was positively correlated (P < 0.004) with the mean sieve aperture estimated to retain 50% of the fragments between successive sieve apertures (MRA). Degradation rate of potentially degradable NDF (PDF) and level of indigestible NDF were not related (P > 0.10) to MRA of masticated and ground fragments. Estimates of tau were positively related to MRA, with slopes of bermudagrass < corn silage < ruminal fragments of corn silage. It was concluded that fragment size-, and consequently, ruminal age-dependent onset of PDF degradation of a mixture of different fragment sizes results in an age-dependent rate of degradation of the more rapidly degrading of two subentities of PDF. Models are proposed that assume a tau before onset of simultaneous degradation of PDF from two pools characterized as having gamma-modeled age-dependency and age-constant rates. The ruminal age-dependent pool seems to be associated with the faster-degrading pool, and its rate parameter increases with range in MRA in the population of fragments. Conceptually, the ruminal age-dependent rate parameter for PDF degradation seems to represent a composite of several effects: 1) effects of the size-dependent tau; 2) range in MRA of the population of ingestively masticated fragments; and 3) subentities of PDF that degrade via more rapid age-dependent rates compared with subentities of PDF that degrade via age-constant rates. The estimated fractional rates of ruminative comminution of ingestively masticated fragments (0.060 to 0.075/h) were of a magnitude similar to the mean fractional rates of PDF digestion (0.030 to 0.085/h), which implies that ruminative comminution may be first-limiting to fractional rate of PDF digestion. The in vivo roles of ingestive and ruminative mastication of fragments on PDF degradation must be considered in any kinetic system for estimating PDF digestion in the rumen. These results and others in the literature suggest that the rate of surface area exposure rather than intrinsic chemical attributes of PDF may be first-limiting to degradation rate of PDF in vivo.     

Mechanism of Action of Probiotic Function of Lactobacilli

乳酸杆菌作为益生菌广泛用于人和动物.本文综述了乳酸杆菌改善宿主健康的机制.乳酸杆菌可通过产生抗菌物质如乳酸、过氧化氢、细菌素,或者通过竞争营养或肠道黏附位点来抑制致病菌;通过诱导黏附素的分泌或阻止细胞凋亡而增强肠道的屏障功能,从而保护肠道.文章重点讨论了乳酸杆菌表面成分(表面蛋白、脂磷壁酸和肽聚糖)与肠道受体(C型凝集素受体、Toll样受体和Nod样受体),阐述了他们结合后启动免疫调节信号,调控肠道免疫功能以发挥改善健康作用的机制.     

Evaluation of serum concentrations of biomarkers of skeletal metabolism and results of radiography as indicators of severity of osteochondrosis in foals

OBJECTIVE: To determine whether serum concentrations of biomarkers of skeletal metabolism can, in conjunction with radiographic evaluation, indicate severity of osteochondrosis in developing horses. ANIMALS: 43 Dutch Warmblood foals with varying severity of osteochondrosis. PROCEDURE: 24 foals were monitored for 5 months and 19 foals were monitored for 11 months. Monthly radiographs of femoropatellar-femorotibial and tibio-tarsal joints were graded for osteochondral abnormalities. Serial blood samples were assayed for 8 cartilage and bone biomarkers. At the end of the monitoring period, foals were examined for macroscopic osteochondrosis lesions. RESULTS: Temporal relationships were evident between certain serum biomarkers and osteochondrosis severity in foals during their first year. Biomarkers of collagen degradation (collagenase-generated neoepitopes of type-II collagen fragments, type-I and -II collagen fragments [COL2-3/4C(short)], and cross-linked telopeptide fragments of type-I collagen) and bone mineralization (osteocalcin) were positive indicators of osteochondrosis severity at 5 months of age. In foals with lesions at 11 months of age, osteochondrosis severity correlated negatively with COL2-3/4C(short) and osteocalcin and positively with C-propeptide of type-II procollagen (CPII), a collagen synthesis marker. Radiographic grading of osteochondrosis lesions significantly correlated with macroscopic osteochondrosis severity score at both ages and was strongest when combined with osteocalcin at 5 months and CPII at 11 months. CONCLUSIONS AND CLINICAL RELEVANCE: The ability of serum biomarkers to indicate osteochondrosis severity appears to depend on stage of disease and is strengthened with radiography. In older foals with more permanent lesions, osteochondrosis severity is significantly related to biomarker concentrations of decreased bone formation and increased cartilage synthesis.