铜在反刍动物营养中的研究进展

铜是反刍动物必需微量元素之一,在反刍动物机体内具有很广泛的分布及多种生物学功能.综述了铜在动物体内的生理功能、吸收代谢及影响吸收代谢的因素以及铜的来源和需要量.     

微量元素铜在反刍动物生产中的应用研究进展

铜在反刍动物体内有着非常重要的作用,它是维持反刍动物机体正常生理功能、生化代谢及生长发育所必需的微量元素,很多依赖于铜的酶在机体内发挥着重要作用,青藏高原的牧草由于冷季缺乏铜而导致放牧家畜容易出现铜缺乏症状,影响放牧家畜的生长及生产性能的提高,为此需要给放牧家畜补充一定量的铜,但是铜在反刍动物体内的吸收率较低且受到很多因素的影响,可以通过研究这些因素来提高铜的吸收效率,以避免对环境造成污染。铜可以促进瘤胃微生物生长,提高产气量和能量利用效率来提高瘤胃发酵效率和营养物质消化率,还可以提高反刍动物免疫功能和抗氧化性能,最终铜可以提高反刍动物的生产性能,不同反刍动物或者相同反刍动物在不同的生理阶段对铜的需要量不一致,在添加铜时要按照营养需要量结合生产实际添加,以提高铜的添加效率。文章综述了铜吸收及影响因素、铜对反刍动物瘤胃发酵、营养物质消化率、免疫功能、抗氧化性能、生产性能的影响,旨在为铜在反刍动物生产中科学应用提供借鉴和参考。     

高铜改善猪生产性能和促进生长作用的机理

铜是人和动物的必需微量元素之一。其营养需要量为：成人2～3mg／d；哺乳动物5～10mg／kg饲料；禽类为4～11mg／kg饲料。通常，人们根据营养需要量供给动物铜、但在特殊要求条件下，根据需要及动物机体功能状态不同对铜供给量     

微量元素铜在反刍动物生产中的应用研究进展

铜在反刍动物体内有着非常重要的作用,它是维持反刍动物机体正常生理功能、生化代谢及生长发育所必需的微量元素,很多依赖于铜的酶在机体内发挥着重要作用,青藏高原的牧草由于冷季缺乏铜而导致放牧家畜容易出现铜缺乏症状,影响放牧家畜的生长及生产性能的提高,为此需要给放牧家畜补充一定量的铜,但是铜在反刍动物体内的吸收率较低且受到很多因素的影响,可以通过研究这些因素来提高铜的吸收效率,以避免对环境造成污染。铜可以促进瘤胃微生物生长,提高产气量和能量利用效率来提高瘤胃发酵效率和营养物质消化率,还可以提高反刍动物免疫功能和抗氧化性能,最终铜可以提高反刍动物的生产性能,不同反刍动物或者相同反刍动物在不同的生理阶段对铜的需要量不一致,在添加铜时要按照营养需要量结合生产实际添加,以提高铜的添加效率。文章综述了铜吸收及影响因素、铜对反刍动物瘤胃发酵、营养物质消化率、免疫功能、抗氧化性能、生产性能的影响,旨在为铜在反刍动物生产中科学应用提供借鉴和参考。     

微量元素铜代谢研究进展

综述了微量元素铜在机体内的吸收、运转、细胞内的分布和排泄，铜的生物学功能，铜与畜禽健康，铜缺乏症，铜中毒症，铜的需要量与供给和影响饲料铜吸收利用的因素等方面的研究状况，强调了铜的生物学作用和畜禽健康，认为铜的基因调控机制应予深入研究。     

不同形式的铜源在猪上的应用探讨

铜是动物体内必需的微量元素之一,在机体新陈代谢、生长发育及维持生产性能等方面均具有重要作用,随着科学技术的不断发展,不同形式的铜源逐渐出现,综述铜的生物学特性、不同形式铜源在猪上的应用及不同质量浓度的铜添加量对猪各阶段生长性能的影响.目的是引导饲料企业和广大养殖户不要盲目的追求高铜,选择好的铜源,使用低铜同样可以达到很理想的养殖效果,合理利用铜源和铜的剂量,促进养殖业的健康发展.     

微量元素铜的研究进展

铜是所有低等生物和脊椎动物必需微量元素之一，在动物体内以不同的方式发挥着特殊的生理作用。随着近年来人们对铜的研究的不断深入越来越受到关注。下面就几个方面详述铜的研究进展。体内的铜含量、分布及需要量铜在体内的含量仅为１～２ｐｐｍ。铜广泛存在于各组织细胞...     

蛋鸡粪便铜排泄率的研究

试验蛋鸡分为育成和产蛋两个阶段,每个阶段蛋鸡分5组,每组5只鸡采用全收粪法分别收集并测量各组试验鸡的产粪量和采食量,分春、夏、秋、冬四季进行代谢试验,每季连续采样5 d.结果表明,育成、产蛋鸡饲料铜分别平均为11.41 mg/kg和10.02mg/kg;育成、产蛋鸡粪铜分别为20.46和18.19 mg/kg;育成与产蛋鸡平均日产铜分别为0.428和0.519 mg/只.研究表明,粪铜与料铜水平相关性较好,铜排泄率随摄入的铜增加而提高;产蛋鸡的铜排泄率低于育成鸡,铜在产蛋鸡和育成鸡的分配模式上不同.研究结果为推进环境友好型蛋鸡业的发展提供基础依据.     

肉牛微量元素铜的营养

铜是人和动物所必需的微量元素,大量的试验研究已证实,铜具有广泛的生物学作用,它与畜禽的生长性能、繁殖性能、免疫功能等都有密切的联系。铜的缺乏对畜禽的造血功能、神经系统、骨骼生长、结缔组织和被毛生长发育等均会造成不同程度的不良影响。本文从肉牛对铜的需要量、影响铜需要量的因素以及肉牛对铜的耐受量等方面概述了近些年来的进展。     

饲料中铜对猪促生长作用机理及在养猪生产中的应用

铜是动物机体必需的微量元素之一,在机体造血、新陈代谢、生长繁殖、维持生产性能、增强机体抵抗力等方面具有不可替代的作用。猪对铜的需要量为4～6mg/kg饲粮。但自发现饲料中添加正常需要量10倍的铜可以明显的提高猪的生长性能以来(Braude,1945),高剂量铜(>125mg/kg)作为一种高效而廉价的促生长添加剂,在畜禽养殖业中被大量使用(刘晓波等,1997)。     

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.