功能性蛋白短肽的蛋白酶法生产研究

随着动物营养科学在蛋白质与氨基酸领域科学研究的不断进展，蛋白短肽作为一种生命活性物质的诸多功能日益被人们所认识，完全可以预见，在不久的将来，活性蛋白短肽在动物营养与动物领域中会表现出更大的作用，将改变对饲料蛋白质质量的评价体系。     

功能性蛋白短肽的蛋白酶法生产研究

1前言随着动物营养科学在蛋白质与氨基酸领域科学研究的不断进展,蛋白短肽作为一种生命活性物质的诸多功能日益被人们所认识,完全可以预见,在不久的将来,活性蛋白短肽在动物营养与动物领域中会表现出更大的作用,将改变对饲料蛋白质质量的评价体系。1.1小肽的营养吸收现代营养研究表明:蛋白质在动物消化道中消化酶的作用下,水解终产物为游离氨基酸和肽,而由数个氨基酸残基组成的短肽可以以完整的形式被吸收利用,而非以前人们所认为的以游离氨基酸形式被吸收。小肽逆浓度梯度,依据H 浓度或Ca2 浓度的主动转运过程,具有pH依赖性的非耗能性Na …     

肽营养及其在开发大豆肽饲料中的应用

文中就大豆肽蛋白饲料研究的时代背景与蛋白质肽营养进行了介绍。日粮蛋白质在消化过程中释放出大量的小肽物质,表明饲料蛋白不仅具有营养功能,还具有调节机体生理机能的功效,在对饲料蛋白的生物学价值进行评定时要将这两者结合起来进行综合评定。特别是许多组成活性小肽的氨基酸并不全是必需氨基酸,启迪人们可以利用那些原本生物效价不很高的蛋白质(如豆粕)资源,生产出更能满足动物需要,与鱼粉等优质动物蛋白原料等价的功能性肽蛋白饲料。     

肽营养理论及其在开发大豆肽蛋白饲料中的应用

本文就大豆肽蛋白饲料研究的时代背景与蛋白质肽营养进行了介绍。日粮蛋白质在消化过程中释放出大量的小肽物质,表明饲料蛋白不仅具有营养功能,还具有调节机体生理机能的功效,在对饲料蛋白的生物学价值进行评定时将这两者结合起来进行综合评定。特别是许多组成活性小肽的氨基酸并不全是必需氨基酸,启迪人们可以利用那些原本生物效价不很高的蛋白质(如豆粕)资源,生产出更好的能满足动物需、与鱼粉等优质动物蛋白原料等价的功能性肽蛋白饲料。     

肽营养理论及其在开发大豆肽蛋白饲料中的应用

本文就大豆肽蛋白饲料研究的时代背景与蛋白质肽营养进行了介绍。日粮蛋白质在消化过程中释放出大量的小肽物质，表明饲料蛋白不仅具有营养功能，还具有调节机体生理机能的功效，在对饲料蛋白的生物学价值进行评定时要将这两者结合起来进行综合评定。特别是许多组成活性小肽的氨基酸并不全是必需氨基酸，启迪人们可以利用那些原本生物效价不很高的蛋白质（如豆粕）资源，生产出更好满足动物需要、与鱼粉等优质动物蛋白原料等价的功能性肽蛋白饲料。     

迁址公告

肽白金是从大豆蛋白中提取的氨基酸短肽。特定的蛋白短肽能调控内分泌，直接参与蛋白质的合成，加快蛋白质的合成速度，提高生产性能，显著提高日增重和饲料转化率。     

反刍动物肽营养研究进展

蛋白质在动物营养中起着重要作用,大量研究已表明蛋白质营养不仅是游离氨基酸营养,肽营养也具有重要作用。本文综述了反刍动物肽的吸收特点及影响因素,肽的吸收代谢机制,肽对瘤胃微生物的调控及对反刍动物生产性能发挥的作用,并阐述饲料蛋白源活性肽的开发应用及肽营养研究与应用前景。     

TAT穿膜肽的研究进展

TAT穿膜肽是近年来发现的一类富含碱性氨基酸的短链多肽,具有较强的穿透细胞膜的能力,与核酸分子、药物蛋白分子甚至病毒体表面分子链接后,能将这些物质顺利带入细胞内发挥作用,被称为"生物导弹"。笔者从4个方面对TAT穿膜肽进行介绍,不仅为深入阐述TAT蛋白转导肽跨膜转导作用的功能意义提供了依据,而且为TAT蛋白转导肽在微生物工程、蛋白质工程及药物靶向治疗等领域的潜在应用价值提供了重要参考。     

碱性蛋白酶酶解法加工羽毛粉

本实验运用碱性蛋白酶将废弃羽毛加工成羽毛粉,使羽毛中的角蛋白转化为肽蛋白,并运用凯氏定氮法测定反应后肽蛋白的含量.加入三氯乙酸可以证明反应后所得到的肽蛋白的组成是不超过四个氨基酸残基的.也就是说大部分角蛋白被转化成了易被动物消化的肽蛋白,极大地提高了动物对蛋白质的消化率.实验结果表明近80％的角蛋白可以通过此方法被转化成肽蛋白,证明羽毛粉在工业上的开发是具有可行性的.     

在乳猪教槽料中应用不同类型小肽对乳猪生产性能的影响

随着检测技术的不断提高和蛋白质代谢深入研究，人们对蛋白质营养的认识有了更进一步的提高。研究表明，肽在动物体内有着独立氨基酸的代谢途径和机制，肽可被动物胃肠道完整的吸收转运，被动物组织所利用(Hara等，1984)；动物对小肽的吸收不仅具有速度快、耗能低、不易饱和等特点，而且可以消除游离氨基酸的吸收竞争(Silk等1980)，当蛋白     

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。     

中华人民共和国农业部公告 第267号

为贯彻落实《兽药生产质量管理规范》(简称《兽药GMP》),进一步推动兽药GMP实施进程,我部制定了《兽药生产质量管理规范检查验收办法》,现予公告。本公告自2003年6月1日起施行。附件:兽药生产质量管理规范检查验收办法二○○三年四月十日第一章 总则 第一条 为推动《兽药生产质量管理规范》(以下简称兽药GMP)的实施,规范兽药GMP检查验收工作,制定本办法。 第二条 农业部负责全国兽药GMP管理和检查验收工作;负责制修订兽药GMP检查验收管理规定;负责兽药GMP检查员队伍建设和监督管理工作,负责国际兽药贸易中GMP互认工作。 …     

鸡败血支原体垂直传播模式及其阻断方法

以国际标准强毒Ｒ株人工感染非免疫产蛋鸡,定时扑杀,分别从鼻窦、眶下孔、气管、肺、气囊、卵巢和输卵管分离ＭＧ,并收集感染鸡所产蛋分离ＭＧ。结果表明,人工感染４８小时后上、下呼吸道及肺已被全面感染,９６小时气囊已被感染,１２０小时输卵管已能分离到ＭＧ,卵巢始终分离不到ＭＧ。人工感染鸡自１４４小时便能在其所产蛋中分离出ＭＧ。药物治疗能在７２小时内消除感染,油乳剂苗则需２４天后逐渐降低蛋内ＭＧ分离率,药物卵内注射、种蛋药浴、高温处理均能杀死卵内ＭＧ,但以研制的种蛋浸泡剂药浴效果为最好。     

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.