铜的代谢及营养生理作用

1铜在动物体内的代谢1.1分布铜在动物体内广泛分布于各种组织和细胞中,正常动物机体内含铜2~3 mg/kg,绝大多数存在于肌肉和骨骼中,肌肉组织约占总量的一半,体组织的铜主要分布在肝、脑、肾、心和毛发。不同组织含铜量不同,对日粮铜含量变化的敏感度也不同。肝是动物贮铜的主要器官,肝铜可以作为评价铜营     

饲料生产和贮存中影响维生素稳定性的因素

维生素是一类动物代谢所必需而需要量极少的低分子有机化合物,它们主要以辅酶和催化剂的形式广泛参与体内代谢的多种化学反应,从而保证机体组织器官的细胞结构和功能正常。如果缺乏可引起机体代谢紊乱,影响动物健康和生产性能,严重时可导致动物死产。     

微量元素在生猪养殖中的作用

1锌锌通过影响动物组织分裂、分化和再生,可从根本上调节猪的生长发育。锌分布于机体的所有组织中,其中以肌肉、肝脏、皮毛等器官组织中锌的浓度较高。锌在动物体内许多酶中和蛋白质结构中发挥重要作用,维持动物生长发育、物质代谢及免疫机能。锌显著影响胸腺、淋巴细胞中T细胞的发育以及白细胞对疾病的吞食和杀灭作用。缺锌使猪体内过氧化物增多,维生素C需求加大,生物膜上的脂肪和硫基氧化受损,对于母猪可使子宫衰退,影响乳     

微量元素锌与家兔生产

自从１９３４年Todd、Bertrand等发现锌为动物的必需微量元素以来，锌的营养作用已受到人们的广泛重视，并做了大量的研究。随着科技的发展和研究手段的提高，人们发现合理的锌水平可保证动物各组织、器官功能处于最佳状态，强化动物的防御、免疫系统，加速机体的生长发育，并能提高繁殖性能等。现就锌在家兔营养中的作用作一综述。１锌在家兔体内的分布与代谢锌广泛存在于动物机体一切组织细胞中，为细胞生长所必需。家兔体内含锌量较高，约５０mg／kg。主要分布在皮肤、被毛、骨骼肌、骨骼、肝脏、睾丸和前列腺中，其他组织中也含锌，但…     

畜禽铅砷中毒的临床症状及防控措施

<正>铅和砷及其化合物对动物都有毒性,铅对畜体主要是重复剂量的慢性积累,中毒对神经系统,造血功能和血管病变特别明显;砷可影响细胞代谢的正常进行,引起多种组织器官的功能扰乱和器质性病变,所以必须引起养殖场(户)的高度重视。1主要来源铅为重金属元素,是动物中毒的常见因素,其来源主要为日粮和饮水,畜禽主要通过消化道和呼吸道     

微量元素铜的生物学特性及其在奶牛生产中的应用

铜是动物机体必需的微量元素之一,主要分布于机体的肝脏、肾脏、脑、心脏及毛发中,肝脏既是微量元素铜的贮存库,也是铜代谢的重要器官;铜在动物机体中通过酶系统发挥着抗氧化作用及维持机体的免疫机能,铜的缺乏及过量均对动物的生长及生理机能产生重要的影响。本文主要介绍了微量元素铜的生物学特性、铜缺乏与过量及铜的不同形式对奶牛产生的影响,为微量元素铜在奶牛生产上的应用提供参考。     

动物砷毒性研究进展

介绍了动物生产中砷的来源和砷在动物体内的吸收、分布、代谢,综述了砷对动物的危害及其机理、砷与其他养分之间的关系以及饲料中砷的最大允许量。     

锌对家兔的营养作用

自从 1 934年Ｔｏｄｄ、Ｂｅｒｔｒａｎｄ等发现锌为动物的必需微量元素以来 ,随着科技的发展和研究的深入 ,人们发现适宜的锌水平可保证动物各组织、器官功能处于最佳状态 ,并能强化动物的抗病、免疫系统 ,加速机体的生长发育 ,提高繁殖性能等。本文就锌在家兔营养中的作用作一综述。1　锌在家兔体内的分布与代谢锌广泛存在于动物机体一切组织细胞中 ,为细胞生长所必需。家兔体内含锌量较高 ,约 5 0ｍｇ/ｋｇ ,主要分布在皮肤、被毛、骨骼肌、骨骼、肝脏、睾丸和前列腺中 ,表明锌与机体生长、皮毛生长、精子成熟都有重要关系。在家兔等单胃…     

哺乳动物妊娠期钙代谢的研究进展

哺乳动物体内的钙代谢通常包括钙平衡和钙稳态。钙平衡是指体内总钙含量保持相对恒定的状态,钙稳态则指细胞内外的钙离子浓度保持稳定。肾脏、肠道、骨骼及雌性动物乳腺是动物体钙代谢的主要器官,其中存在着许多精细而复杂的调控网络。妊娠期钙代谢紊乱会严重影响母畜及胎儿的营养健康,维持体内钙代谢稳态对围产期哺乳动物尤为重要。本文综合近年来国内外妊娠期哺乳动物钙代谢相关研究,从不同组织器官钙代谢情况及钙代谢过程中重要的调节因子的调控作用进行综述,旨在为妊娠期哺乳动物钙代谢调控相关研究提供思路。     

硫酸亚铁在畜牧业上的应用

硫酸亚铁含铁量为 2 0 .0 9% ,在畜牧兽医上主要用于防治缺铁性疾病 ,作为饲料微量元素添加剂或用于棉籽饼脱毒 ,也可用于缺硫性疾病的防治。动物体内铁的含量随动物的种类、年龄、性别、健康状况、营养等的不同 ,变化较大。动物体内的铁主要分布于血红蛋白、肌红蛋白中 ,有少量分布于细胞色素载体化合物及酶系统中。肝、脾、骨髓是主要贮铁器官。动物缺铁主要表现为贫血、幼畜腹泻 ,生长发育迟缓、昏睡、可视粘膜苍白、抗病力弱 ,严重缺铁时死亡。动物缺硫主要表现为消瘦 ,角、蹄、爪、毛、羽生长缓慢 ,严重缺硫时 ,出现啄羽、脱毛等。预防…     

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.