γ-氨基丁酸抗应激作用的研究

为了研究γ-氨基丁酸(GABA)对动物抗应激能力的影响,试验给小鼠灌服γ-氨基丁酸溶液,剂量分为0.25,0.5,1 g/kg,连续灌服20 d,然后分别对小鼠进行负重游泳试验、耐缺氧试验、耐低温作用试验和耐高温作用试验。结果表明:服用γ-氨基丁酸的小鼠在上述试验中的生存时间均比对照组长。说明γ-氨基丁酸具有提高小鼠抗应激能力的作用。     

γ-氨基丁酸的代谢及其在鱼类养殖中的应用研究进展

氨基丁酸是一种广泛存在于动植物体及微生物体内的条件性必需营养素。GABA作为一种重要的抑制性神经递质,在机体内的许多新陈代谢活动中发挥着重要作用。近年来,γ-氨基丁酸作为饲料添加剂已逐步应用于鱼类养殖生产中,在鱼类的生长、食欲及抗应激等方面发挥重要作用。本文主要综述了γ-氨基丁酸理化特性、来源、分布、代谢以及γ-氨基丁酸对鱼类的促生长、抗氧化及免疫等方面作用,为γ-氨基丁酸在鱼类养殖中的合理应用提供参考。     

新型饲料添加剂-γ-氨基丁酸的制备及应用研究进展

γ-氨基丁酸是一种新型饲料添加剂,对畜禽具有抗热应激、促生长等作用.γ-氨基丁酸具有效果显著、安全性高等特点,在畜禽养殖业中有着极其广阔的应用前景.     

γ-氨基丁酸的生物学功能及其在家禽生产中的应用

家禽饲料中加入适量的γ-氨基丁酸可以提高其生产性能、增强机体免疫力、改善产品品质等。论文概述了γ-氨基丁酸的来源、性质,论述了γ-氨基丁酸的生物学功能及其在家禽生产中的应用现状,展望了其发展前景,以期为γ-氨基丁酸的进一步研究开发提供参考。     

γ-氨基丁酸在缓解奶牛热应激上的应用前景

γ-氨基丁酸作为机体一种重要的神经抑制剂,因具有提高食欲、增强免疫力、缓解热应激等作用,已被广泛应用于食品、药品等领域。在我国,奶牛夏季面临严峻的热应激问题,高温严重影响了奶牛正常的生理活动,对此开发具有缓解热应激功能的新型饲料添加剂成为研究热点。目前,γ-氨基丁酸已应用于畜禽生产,但对反刍动物的相关研究少有报道。本文对γ-氨基丁酸的生理功能及其在奶牛热应激中的应用进行了综述,以供同行参考。     

顶复门原虫γ-氨基丁酸代谢旁路研究进展

顶复门原虫包括一大类单细胞寄生性原虫,是人和动物的重要病原,会对人类健康以及畜牧业生产造成严重危害。γ-氨基丁酸是一种四碳非蛋白质氨基酸,广泛存在于生物体内。顶复门原虫的γ-氨基丁酸代谢旁路主要参与能量代谢,为虫体生长提供短期的能量储备,在虫体适应不同寄生环境过程中起着关键性作用。寄生原虫的γ-氨基丁酸代谢明显区别于哺乳动物宿主,仅限于中枢神经系统中的代谢,可在虫体入侵宿主细胞及有性生殖阶段发挥重要的作用。本文对顶复门原虫γ-氨基丁酸代谢途径及其生物学作用进行综述。     

γ-氨基丁酸的生理作用及其在畜牧生产中的应用

γ-氨基丁酸(GABA),是重要的抑制性神经递质。GABA在提高动物采食量及日增重、增强机体免疫、促进动物生长等方面起到了积极的作用。随着对GABA的深入研究,其功能已经应用于各个领域,尤其在畜牧业中对富含GABA的食品饲料的开发及在动物生产中的应用。因此,对GABA的研究具有广阔的前景,本文是对γ-氨基丁酸的生理作用及其在畜牧生产中的应用进行了总结。     

γ-氨基丁酸在畜牧生产上的应用

γ-氨基丁酸是一种重要的功能性非蛋白质氨基酸,具有提高动物采食量,改善胴体品质,增强免疫功能、生殖性能和抗缺氧能力以及缓解热应激等作用。本文主要综述γ-氨基丁酸在畜牧生产中的应用。     

γ-氨基丁酸在动物生产中应用的研究进展

γ-氨基丁酸(GABA)又称γ-氨酪酸、4-氨基丁酸,是动物神经系统中主要的抑制性神经递质,也是广泛存在于植物体内的一种与逆境胁迫有关的非蛋白氨基酸。1950年,有学者发现γ-氨基丁酸存在于哺乳动物的大脑中,并且证明了它是由谷氨酸在谷氨酸脱羧酶作用下经α-脱羧作用生成的。之后,发现γ-氨基丁酸在哺乳动物大脑中模仿内源性神经     

GABA的生物学功能及其在养鸡生产中的应用

作为哺乳动物中枢神经系统内重要的抑制性神经递质,γ-氨基丁酸(GABA)是一种重要的功能性非蛋白质氨基酸,具有提高动物采食量、泌乳量、改善胴体品质、缓解热应激、提高内分泌和免疫机能等显著生理作用。近年来研究表明,GABA因其作用的高效性和使用的安全性,已经成为一种新型的绿色饲料添加剂。本文简述了γ-氨基丁酸的生物学功能并对其在养鸡生产中的应用现状、研究前景进行了综述和展望。     

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.