花生四烯酸在水产饲料中的应用

花生四烯酸是鱼类的一种必需脂肪酸。作为水产饲料添加剂,花生四烯酸有利于海洋鱼类生长、存活及抵抗压力,提高卵子、精子和幼苗的质量,从而促进鱼类的繁殖,花生四烯酸还具有调节免疫的功能。本文还简述了利用生物技术发酵生产花生四烯酸。     

前列腺素对禽类等级卵泡发育的影响

前列腺素是一类由花生四烯酸通过环氧化酶途径合成的脂类介导物。在哺乳动物排卵、受精、胚泡植入、蜕膜化、子宫平滑肌收缩、黄体退化及卵泡发育过程中起重要作用。对于家禽,前列腺素促进其产卵和子宫收缩;在产卵中期,卵巢静脉血浆中前列腺素的浓度为外周血浆浓度的5～20倍。这种高剂量、脉冲式分泌的前列腺素不仅能促进家禽成熟卵泡的排卵,而且可作为促性腺激素的第二信使介导颗粒细胞对cAMP的反应,促进了等级前卵泡颗粒细胞的增殖,进而在优势卵泡的选择过程中起重要作用。     

花生四烯酸在畜禽业中的应用

介绍了花生四烯酸的作用机理,综述了其在动物繁殖、生产富含脂肪酸保健蛋等方面的应用,指出了花生四烯酸的开发应用前景。     

寄生虫介导的花生四烯酸代谢物免疫调节

宿主感染寄生虫的一个显著表现是在感染期间不能发生有效的免疫反应。花生四烯酸代谢物可能在这一现象中起重要作用。大量的研究证据表明，寄生虫释放花生四烯酸代谢物；寄生虫花生四烯酸代谢物抑制宿主免疫细胞功能，从而有利于寄生虫的入侵和生存；寄生虫也激发宿主细胞产生花生四烯酸代谢物。     

如何利用脂肪饲喂肉用仔鸡

<正> 脂肪与其它成分一样是家禽日粮中的重要组成部分。它不仅是家禽可消化能的来源,而且还是不可取代的脂肪酸(亚油酸,亚麻酸,花生四烯酸)的来源。另外。脂肪中还含有抗氧化剂和脂溶性维生素(A、D、E和K)。在配合饲料中添加脂肪的价值还在于它能改善饲料结构,降低含尘量。富含脂肪的混合饲料适口性较强,饲喂效果好。     

营养因素对禽病防治的影响

日粮所含脂肪酸作为一种营养素，是动物体内能量的重要来源，同时供给机体所需的必需脂肪酸，在机体代谢中发挥着重要的作用，它对动物机体免疫功能的影响也逐渐被人们所揭示。日粮中的脂肪酸通过改变细胞膜的结构或调节前列腺素的合成来影响家禽的免疫能力，前列腺素能降低抗体水平，对包括免疫反应的许多生理过程起着重要的调节控制     

饲用油脂的营养价值及其在畜禽日粮中的应用

在畜禽日粮中使用饲用油脂的重要目的是提供高质量的能量来源。随着动物营养研究的不断深入,添加油脂作为能量饲料越来越受到动物营养学家的推崇。饲用油脂的重要饲用价值表现在如下几个方面:(1)提供高浓度、易利用的代谢能。代谢能价值是碳水化合物和蛋白质的2.25倍。(2)提供动物体内所需的必需脂肪酸(亚油酸、亚麻酸和花生四烯酸)。(3)促进脂溶性维生素和类胡萝卜素(色素)的吸收和利用。(4)改善饲料的适口性和外部感观,提高动物的采食量。(5)在特殊环境,尤其是高温条件下,可以减少动物的应激反应。(6)减少饲料生产过程中的粉尘和饲养过程中饲料的浪费,减少饲料机械的磨损,防止饲料组分的分级。     

花生四烯酸在水产动物中的应用

本文就近年来花生四烯酸(20∶4n-6,ARA)对水产动物的营养作用进行综述。     

益生菌对家禽肠道微生态的调控及其应用

益生菌是一类对宿主健康有益的活性微生物,定植于动物肠道或生殖系统内,具有提高消化酶活性、维持肠道微生态平衡及调节宿主黏膜与免疫系统等功能。益生菌作为饲料添加剂在畜禽养殖中的应用是实施健康养殖的重要技术手段之一,在提高动物生产性能、增强畜禽抵抗力及抗生素替代方面都有良好的应用前景。研究对益生菌在家禽生产中对肠道微生态调节的调控机制及其对家禽生产性能、疾病防治及在饲料添加剂中的应用等方面进行综述,进一步了解益生菌的应用前景。     

营养因素对禽病防治的影响

1饲料中脂肪水平对疾病预防的影响日粮所含脂肪酸作为一种营养素,是动物体内能量的重要来源,同时供给机体所需的必需脂肪酸,在机体代谢中发挥着重要的作用,它对动物机体免疫功能的影响也逐渐被人们所揭示。日粮中的脂肪酸通过改变细胞膜的结构或调节前列腺素的合成来影响家禽的     

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。     

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。     

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.     

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。     

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.     

獭兔睾丸的组织学观察

家兔作为一种实验动物 ,推动了繁殖技术的发展。本试验通过对不同年龄公獭兔的睾丸进行组织学观察、测定 ,研究精子的发生规律 ,为系统地进行繁殖生理工作提供依据。1　材料与方法选 60日龄、75日龄、90日龄 3个年龄公獭兔各5只 ,用外科手术法摘取两侧睾丸 ,放入 Bouin氏液中固定 ,二甲苯透明 ,石蜡包埋 ,切成 5～ 8μm切片 ,H.E.染色。在显微镜下观察 ,并进行定量组织学指标测定及差异性比较。2　结果和讨论2 .1　睾丸定量组织学指标的测定结果　见表 1。表 1　獭兔睾丸定量组织学指标　　　μm,个 /精细管60日龄 75日龄 90日龄曲细精管…     

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.