饲料中鱼源性成分真实性鉴别研究

研究旨在建立标准化的饲料中鱼源性成分的PCR检测方法,以形成行业标准推广使用.应用鱼源性引物对35种鱼类、24种非鱼类动物和10种植物样品进行PCR检测,只在35种鱼类中出现224 bp特异扩增条带,在其他的非鱼类动植物DNA中未出现扩增条带.实验表明,PCR检测方法具有特异性,检测限为0.1 ng DNA和0.1 %(W/W).应用该方法对上海口岸进口的100个鱼粉样品进行检测,均能检出鱼源性成分.研究建立的标准化饲料中鱼源性成分PCR检测方法能应用于日常检验检疫工作,可推广使用.     

实时荧光PCR法检测饲料中牛、羊源性成分

为了快速准确地检测饲料中牛、羊源性成分,试验采用实时荧光PCR方法,分别以牛、羊各自物种特异性基因为研究对象,设计实时荧光PCR扩增的特异性引物及探针,建立饲料中牛、羊源性成分的实时荧光PCR检测方法。结果表明:该检测方法特异性强、灵敏度高(达到0. 01%),可以作为饲料中牛、羊源性成分检测的常规方法。通过对15种市售饲料样品进行检验,结果 2种饲料骨粉未标明含有羊源性成分,但检出;1种饲料骨粉标签中未标明成分,但检出牛源性成分,证实该方法操作简便快捷,可以快速、准确、大批量地开展饲料的日常检测工作。     

实时荧光PCR和常规PCR方法检测饲料中鸡源性成分

根据鸡线粒体DNA序列,设计并筛选了鸡源性特异引物及探针,建立了饲料中鸡源性成分的常规PCR和实时荧光PCR检测方法,结果表明常规PCR方法最低可以从饲料中检出0.1%的鸡源性成分,实时荧光PCR方法最低可以从饲料中检出0.001%的鸡源性成分。该方法具有很高的特异性和灵敏性,可以作为鸡源性成分鉴别检测的常规方法。     

饲料中牛、羊源性成分现场可视化检测方法的建立

根据牛、羊线粒体中物种特异性序列设计引物,应用可视化环状等温扩增技术（visual loop-mediate isothermal amplification,vLAMP）对牛、羊源性成分进行快速扩增及可视化判断,同时建立牛、羊源成分人工污染的饲料模型,考察vLAMP检测方法的灵敏度。结果表明,牛源性引物和羊源性引物仅分别对牛、羊源性成分产生特异性扩增,灵敏度高达0.001%。本试验所建立的牛、羊源性成分现场可视化筛查方法具有较高的特异性与灵敏度,操作简单、快速,可用于饲料中牛、羊源性成分污染和食品掺伪的现场可视化检测。     

进口饲料中牛源性与转基因成分的检测

本文介绍了进口饲料中牛源性与转基因成分的PCR检测方法。该方法用异硫氰酸胍提取进口饲料样品DNA,以牛特异性引物扩增模板DNA,扩增产物为271bp,PCR产物经限制性酶切片段分析,与预期设想一致;方法灵敏度实验结果显示,饲料样品中含有0.1%的牛源性成分时仍能检出。同时,根据转基因农作物最常使用的外源基因设计引物,在进口饲料中检测出35S启动子和NOS中止子等转基因成分,具有快速、简便、准确等特点。     

根据线粒体基因的特异性鉴别检测饲料中的动物源性成分

为了防止海绵状脑病疫区和痒病疫区的反刍动物源性饲料入手动物食物链，继而进入人类消费的食物链，因而，非常用必要对贸易往来中的肉骨粉品种来源进行鉴定检测。我们运用聚合酶链反应技术（Polymerase Chain Reaction,PCR），以检测不同种动物特异性线粒体基因片段为目标，分别建立了从动物源性饲料中鉴别检测猪、鸡、马成分的方法。该方法具有灵敏度高、快速和特异性强的优点，可作为动物源性饲料中猪、鸡、马源性成份鉴别检测的常规方法之一。     

PCR方法扩增种属特异性片段检测猪源成分

针对猪线粒体基因的保守序列,设计特异性引物,优化反应条件和反应参数,建立了食品和饲料中猪源性成分的PCR检测方法。该方法灵敏、特异,检测低限达0.01%。其推广使用,对于加强食品、饲料的质量控制和监督监管,具有参考价值。     

动物产品及饲料中牛源和羊源性成分三重荧光PCR检测方法的建立

为鉴定和区分饲料及动物产品中牛、山羊、绵羊源性成分,根据线粒体DNA(mitochondrial DNA,mtDNA)种间保守序列,设计合成了3对特异性引物与TaqMan探针,通过对荧光PCR反应体系和反应条件的优化筛选,建立了三重荧光PCR方法,在同一个荧光PCR反应中完成3种动物源性成分的检测。用该方法对16种不同源性的动物DNA进行检测,结果表明能特异地鉴别检测出牛、山羊和绵羊源性成分,且敏感性比现行国标PCR法高100倍。该方法适用于饲料、肉制品、奶制品等动物源性产品的检测。     

变性高效液相色谱高通量检测动物源性饲料中沙门氏菌和志贺氏菌

应用复合PCR结合变性高效液相色谱(DHPLC)技术,通过通用增菌培养,建立动物源性饲料中沙门氏菌和志贺氏菌的快速高通量检测方法.根据沙门氏菌和志贺氏菌特异基因序列分别设计特异性引物,复合PCR扩增的产物经DHPLC技术进行快速检测.以49株参考菌株做特异性试验,并开展了精密度检测试验.试验结果表明,该方法具有很好的特异性和精密度,经通用增菌和复合PCR-DHPLC技术可同时检测饲料中的沙门氏菌和志贺氏菌.该方法可以快速、准确、高通量检测,是动物源性饲料中致病菌高通量检测的新技术.     

饲料及动物性食品中山羊源性和绵羊源性成分双重荧光PCR检测方法的建立

目的建立一种能同时检测饲料及动物性食品中的山羊和绵羊源性成分的双重荧光PCR方法,应用于动物源性饲料及动物性食品的快速检验.方法分别根据山羊、绵羊线粒体种间保守序列,设计合成针对山羊和绵羊的特异性引物及TaqMan探针,通过荧光PCR反应体系和反应条件的优化筛选,建立可同时检测饲料及动物性食品中的山羊和绵羊源性成分的双重荧光PCR方法.结果本研究所建立的双重荧光PCR检测方法可同时快速检测饲料及动物性食品中的山羊和绵羊源性成分,应用本方法检测山羊肉和绵羊肉模板的检出限均为10-5,与相应的单重荧光PCR方法的检出限一致,比国标法(GB/T20190-2006)的灵敏性高100倍.结论本研究建立的双重荧光PCR检测方法特异性好、敏感性强,适用于饲料、肉制品、乳制品等动物源性食品的快速检测     

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.