动物磷营养代谢及其提高磷利用率的主要措施

磷是动物体内必需营养元素之一，磷的吸收代谢直接关系到动物生长及生产潜能的发挥。此文就磷的营养代谢调节、影响磷利用率的主要因素及其改善措施等方面作一综述，从而为生产实践提供一定的理论借鉴。     

钙、磷对动物的重要影响

1 钙、磷对动物的营养作用 钙磷是动物骨骼和牙齿的重要组成成分.钙能调节肌肉和神经的兴奋性,能激活或抑制多种酶的活性,钙还具有自身营养调节功能,在外源钙供给不足时,沉积钙(特别是骨骼中)可大量分解供代谢循环需要,此功能对产蛋、产奶、妊娠动物十分重要.磷是ATP和磷酸肌酸的组成成分,参与体内能量代谢;磷以磷脂的方式促进脂类物质和脂溶性维生素的吸收;磷以磷酸根的形式参与糖、脂肪和蛋白质等的代谢,血液中的磷酸盐同时还是动物体内重要的缓冲物质,参与维持体内酸碱平衡.     

奶牛磷营养的研究进展

磷是奶牛体内第二大矿物质元素,参与机体几乎所有的代谢反应,是机体中作用最广泛的矿物质元素,对机体的健康,生产性能和繁殖性能都有重要影响。但过量的磷使粪磷排放增加,造成环境中(土壤和地下水)磷的富集。磷在水中的富集将会导致藻类植物增生,剥夺水生动物所需的氧气,引起生     

植物性饲料有效钙和磷的评定方法

<正>饲料有效钙、磷是指摄入的钙或总磷被动物消化吸收并参与体内代谢过程或贮存在动物组织和产品中的部分(Gueguen等,1977)。饲料有效钙、磷的评定方法包括相对效价法和绝对效价法。其中,相对效价法最具有代表性的就是斜率比法(Slope ratio assay),而绝对效价法又有表观消化率、真消化率和体外消化法。     

豆粕---玉米型日粮中磷的表观消化率研究

磷(Phosphorus)是动物体内的必需矿物元素,在动物体内磷不但是骨骼组织的必要成分,而且在其他代谢功能的正常发挥中起重要作用。由于植物性饲料中的磷大多以植酸磷的形式存在,除小麦外,植酸酶的含量一般都很低,而单胃动物体内缺乏植酸酶或酶活性不高,长期以来人们往     

饲料中磷的生物学效价评定方法

磷是动物营养中所需的常量物质元素之一。在自然界中磷的含量非常丰富,在动物体内约含有4％的矿物质中大约．70％是钙和磷。体内的磷主要以羟磷灰石的形式存在于动物的骨骼和牙齿中,约占体内总磷量的80％,其余的磷存在于细胞内和体液中,主要是作为磷蛋白、核酸、磷脂以及含磷的酶类的构成成分。磷在动物体内具有重要的生理功能,它是许多器官的有机组成成分,参与体液的内稳恒机制,保证细胞膜的平衡,参与许多物质代谢过程,并影响胃肠道中的微生物区系。 植物性饲料是单胃动物比较好的能量和蛋白饲料,但由于植物性饲料中磷的含量比较低,且有2／3以植酸磷形式存在。由于单胃动物体内缺乏分解植酸磷的内源性酶系统,因而对植酸磷的利用率较低。为满足畜禽的生长需要,人们必须在日粮中添加更多的磷,这不仅会增加饲料成本。而且由于添加到饲料中的磷并不能完全被吸收,势必会严重污染环境,要准确地配制畜禽的全价日粮．就必须弄清各种饲料原料中可以为畜禽利用的营养素的含量,这样就不可避免地涉及到生物学效价问题。本文介绍并综合了现有评定饲料中磷的生物学效价方法。     

钾在动物体内代谢特点及其对电解质平衡的影响

钾在动物体内代谢特点及其对电解质平衡的影响齐齐哈尔市农牧企业局李永和齐齐哈尔华齐联合饲料厂孙宝泉１钾在动物体内代谢特点１１钾在动物体内的分布钾是继钙、磷之后动物体内第三位常量元素，９０％以上的钾存在于细胞内，特别是红细胞内。细胞内的钾是细胞外液的２...     

识别磷酸氯钙掺假的方法

磷是动物机体构成骨骼和牙齿的重要物质元素之一,也是构成动物软组织不可缺少的组成部分,同时,动物机体内许多物质的代谢过程中,磷还以磷酸根的形式参与体内代谢。在动物饲养过程中,磷不足是一种较为普遍的现象,容易引起动物幼雏期佝偻病、成年动物软骨症和骨质疏松症、发情异常和泌乳量下降等病症,而磷吸收过量则会引起甲状旁腺机能亢进,骨骼中磷释放进入血液,造成动物跛行、骨折等症。因此,正确衡定动物日粮中磷添加量对畜牧业生产具有重要意义。     

植物性饲料中植酸磷和植酸酶的研究进展

磷 (Ｐｈｏｓｐｈｏｒｕｓ)是动植物体内的必需矿物元素 ,在动物体内磷不但是骨骼组织的必要成分 ,而且在其他代谢功能的正常发挥中起重要作用。由于植物性饲料中的磷大多以植酸磷的形式存在 ,而单胃动物体内缺乏植酸酶或酶的活性不高 ,长期以来人们往往是按照植物性饲料中磷的有效率为总磷的 1 /3的假设来进行饲料配方 ,有的甚至忽略不计 ,而用无机磷来满足动物对磷的需要量 ,这样势必造成磷源的浪费 ,导致磷的过量排泄。事实上 ,植物性饲料中的磷以植酸磷和非植酸磷两种形式存在 ,非植酸磷并非 1 0 0 %为动物所利用 ,植酸磷的含量也不是简…     

饲料中磷生物学效价评定方法研究进展

磷是动物机体必需的常量矿物质元素之一。在自然界中磷的含量非常丰富，在动物机体内磷的含量仅次于钙。在动物的机体内，磷具有重要生理功能。约90％的磷存在于动物的骨骼中，由这些磷与钙构成骨的无机质。除此之外，磷还参与核酸、磷脂、辅酶的形成，参与和维持机体的正常代谢活动。因此，磷是家畜机体内一种极其重要的矿物质元素。     

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.