不同绵羊品种褪黑激素的季节性及昼夜变化规律研究

系统研究了小尾寒羊、同羊、滩羊血液褪黑激素在春分、夏至、秋分时的昼夜变化规律,发现绵羊血液中褪黑激素存在着明显的季节性变化,在春分和秋分时平均含量相对较低,在夏至时明显升高。在夏至和秋分时,小尾寒羊和同羊血液中褪黑激素比滩羊低,在春分时,小尾寒羊褪黑激素比同羊和滩羊高。     

四个不同节气对哈巴特肉仔鸡血糖值的影响

为比较哈巴特肉仔鸡在春分、夏至、秋分和冬至四个不同节气时的血糖值,分别在同一年度的春分、夏至、秋分和冬至的当天测定12日龄哈巴特肉仔鸡的空腹血糖值.结果表明:哈巴特肉仔鸡的血糖值在夏至时为最低,冬至时为最高,且冬至时极显著地高于春分和夏至(P＜0.01),秋分时极显著地高于夏至(P＜0.01),而血糖值春分和秋分之间无显著性差异(P＞0.05).可见,随着季节的变换,哈巴特肉仔鸡的血糖值也发生相应变化.     

四个不同节气对哈巴特肉仔鸡血糖值的影响

[摘要]为比较哈巴特肉仔鸡在春分、夏至、秋分和冬至四个不同节气时的血糖值,分别在同一年度的春分、夏至、秋分和冬至的当天测定12日龄哈巴特肉仔鸡的空腹血糖值。结果表明：哈巴特肉仔鸡的血糖值在夏至时为最低,冬至时为最高,且冬至时极显著地高于春分和夏至（P〈0．01）,秋分时极显著地高于夏至（P〈0．01）,而血糖值春分和秋分之间无显著性差异（P〉0．05）。可见,随着季节的变换,哈巴特肉仔鸡的血糖值也发生相应变化。     

萨福克羊的种质特性

对肉用种羊萨福克的种质特性进行了研究,结果表明引入和纯种繁殖的萨福克羊成年公羊体重138.5 kg±4.4 kg,母羊96.8 kg±7.2 kg;第二胎产羔率204.8%;纯种繁殖的3月龄公、母羔羊平均体重40.8 kg.繁殖母羊泌乳中期奶中干物质19.64%,比滩羊高4.53个百分点;乳脂率8.95%,比滩羊高4.68个百分点;乳糖含量1.83%,比滩羊低1.67个百分点;萨福克羊奶中有效成分高于滩羊.尽管乳糖是重要的营养物质,但羔羊对乳糖的消化、吸收率低,乳糖量高时发生拉稀,对羔羊产生不利影响.改良本地羊效果表明萨杂屠前活重63.6 kg,为同龄、同性别滩羊的193.3%、小尾寒羊的157.0%;萨杂羊胴体重34.21 kg,为滩羊的231.1%、小尾寒羊的184.5%;萨杂羊的屠宰率56.07%,比滩羊高6.31个百分点,比小尾寒羊高9.60个百分点;萨杂羊净肉率41.33%,比滩羊高2.88个百分点,比小尾寒羊高5.72个百分点;胴体净肉率83.45%,比滩羊高5.93个百分点,比小尾寒羊高10.12个百分点;肉骨比5.04∶1,比滩羊高43.5%,比小尾寒羊高83.27%;眼肌面积24.27 cm2,比滩羊高114.4%,比小尾寒羊高86.2%;熟肉率52.65%,比滩羊低5.11个百分点,比小尾寒羊高2.39个百分点,表明滩羊肉的出品率高于萨杂和小尾寒羊;新鲜肉的pH值均在正常范围内.肉眼观察萨杂眼肌横断面,有明显的大理石纹、即肉脂相间性状,而滩羊和小尾寒羊眼肌横断面无大理石纹.     

我国农区及农牧交错区绵羊与蒙古羊遗传分化研究

采用中心产区典型群随机抽样方法和多种电泳技术检测小尾寒羊、滩羊编码血液蛋白16个结构基因座上的变异，与蒙古国蒙古羊、我国湖羊和同羊的相同资料进行比较分析，探讨其遗传分化关系。除Alp和X-p，结构基因座的基因遗传分化程度均低于7．3417％，群体间遗传差异占5．3705％。标准遗传距离、模糊聚类分析表明，湖羊、同羊、小尾寒羊和滩羊与蒙古羊亲缘关系逐渐疏远。遗传贴近度是否适合用于受研究群体和已知其始祖的现代群体之间的比较有待进一步验证。从结构基因座方面进一步证实小尾寒羊、滩羊的蒙古羊属性，揭示了5个绵羊群体之间的部分遗传差异。     

肉用品种羊与地方品种羊所产杂种羊生长发育及产肉性能测定与分析

用特克萨尔、萨福克、无角陶赛特三个肉用品种公羊杂交改良本地原有的滩羊，寒滩杂种羊，所产后裔在相同的饲养管理条件下．特杂去势周岁公羊活重71．87kg，萨杂均64．26kg，陶杂为64．20kg，分别比同龄、同性别的滩羊高113．90％、91．25％、91．07％；比小尾寒羊高73．18％，54．84％，54.07％。屠宰试验结果表明：三个类群肉用杂种羊屠宰后胴体重比滩羊高97．67％～126．70％，比小尾寒羊高68．40％～93．13％；屠宰率比滩羊高1．72～3．88个百分点，比小尾寒羊高4．19～6．35个百分点；活体净肉率比滩羊高2.21～4.72个百分点，比小尾寒羊高6．61～9．12个百分点；其它指标均显著高于本地滩羊和小尾寒羊，改良效果十分明显。     

宁夏滩羊和引进小尾寒羊的血液生化指标比较分析

为了比较宁夏滩羊和引进小尾寒羊的血液生化指标,试验采用爱德士(IDEXX)Vet Test全自动生化分析仪等仪器对宁夏滩羊和引进小尾寒羊血液生化指标及血液酶类指标进行了测定。结果表明:在宁夏滩羊、小尾寒羊血液中总蛋白、白蛋白、尿素氮、肌肝含量存在极显著差异(P0.01),而其他指标则差异不显著(P0.05);同时,消瘦羊只血液中总蛋白、白蛋白和球蛋白含量较低,临床检查羊只拉稀且已脱水,剖检可以看出消瘦的羊只肝肾功能不全、胃肠道出血等症状,而且各种酶类配合解剖检查都预示消瘦羊只各种脏器功能不全。说明血液生化指标和酶类的检测可以预示羊的健康状况,而且可以在一定程度上区分羊的品种。     

我国蒙古羊系统主要地方绵羊品种遗传分化的研究

应用中心产区典型群简单随机抽样的方法,检测控制湖羊、同羊、滩羊、小尾寒羊和洼地羊的血液酶和其他蛋白质变异的5个结构基因座位(Tf、X-p、Ary-Es、Hb-β、Ke)上的遗传变异,引用国内外学者以相同实验方法获得的其他分布于我国周边国家和地区的11个绵羊品种作为分析背景,对16个群体进行遗传距离分析及亲缘关系聚类。结果表明:中亚以东南绵羊群体可以划分为蒙古羊、藏羊和南亚-东南亚羊三大集团,湖羊、同羊、滩羊、小尾寒羊和洼地羊均属于"蒙古羊"系统。     

我国6个绵(山)羊群体遗传分化的微卫星分析

为进一步了解我国绵(山)羊群体的品种特性及其遗传分化,本文利用微卫星标记对我国6个绵(山)羊群体遗传分化进行了分析。采用中心产区典型群随机抽样方法用聚丙烯酰胺凝胶电泳检测乌珠穆沁羊7个微卫星位点,并引用同实验室小尾寒羊、滩羊、湖羊、同羊、长江三角洲白山羊(参照群体)的相关资料进行群体遗传分化水平分析。研究表明:7个微卫星位点在乌珠穆沁羊、小尾寒羊、滩羊、湖羊、同羊、山羊这6个品种中均存在遗传多态性,各座位等位基因均较丰富。根据标准遗传距离、DA遗传距离以及模糊相容关系进行聚类分析,湖羊与同羊首先聚为一类,乌珠穆沁羊和小尾寒羊聚为一类,然后与滩羊聚为一类,5个绵羊品种最后与山羊相聚。     

不同品种绵羊TGF-β1基因单核苷酸多态性及其与繁殖力关系的研究

以小尾寒羊、滩羊、同羊、欧拉羊共计196头为研究材料，采用PCR—SSCP技术，对绵羊TGF-β1基因6-7外显子区间内的805bp序列进行多态性分析，发现了一个多态位点。经克隆测序分析发现，第6内含子区内存在一个突变，该突变位点为第7外显子上游的第294位碱基处缺失了AGAC（序列：gi76871756中的14201位）。对不同绵羊群的基因型和等位基因频率统计结果表明，多胎品种小尾寒羊以AB基因型为主。x^2检验结果表明，单胎品种滩羊、同羊、欧拉羊以BB基因型为主，所有品种都处于Hardy-Weinberg平衡状态。     

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。     

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。     

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.     

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.     

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。     

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。