肉牛黄体期和卵泡期阴道菌群结构的比较研究

为了研究生殖激素对阴道菌群的影响,选取7头健康肉牛,分别采集黄体期和卵泡期阴道分泌物,提取细菌总DNA,根据DGGE克隆测序结果,选择5种特异性细菌,利用荧光定量PCR技术检测各细菌数量。结果表明,总菌、大肠杆菌、鞘氨醇单胞菌和睡眠嗜血杆菌菌群数量在两组间无显著差异(P0.05),但黄体期链球菌属数量显著高于卵泡期(P0.01),卵泡期乳杆菌属数量显著高于黄体期(P0.05)。结果提示,肉牛黄体期与卵泡期的阴道菌群结构存在显著差异。     

健康与子宫内膜炎奶牛阴道菌群结构的比较研究

利用16SrDNA结合PCR-DGGE技术分析比较了产后45d健康奶牛和患子宫内膜炎奶牛阴道内细菌群落多样性及其差异,并通过切胶、克隆测序等步骤分析了奶牛阴道细菌种类。研究结果表明,患病奶牛DGGE图谱的条带数量、多样性指数均显著高于健康奶牛;健康奶牛阴道优势菌主要有清酒乳杆菌(Lactobacillus sakei subsp.)、魏斯杆菌(Weissella koreensis sp.)和地衣芽孢杆菌(Bacillus licheniformis),而患病组奶牛阴道内此3种优势菌含量显著降低或缺失,且也无其他明显优势菌存在;从健康和患病奶牛阴道内均分离出脆弱拟杆菌(Bacteroides fragilis)、溃疡拟杆菌(Bacteroides helcogenes)、无乳支原体(Mycoplasma agalactiae)、普氏菌(Prevotella dentalis)、产气荚膜梭菌(Clostridium perfringens str.)和肠球菌(Enterococcus hirae)等常见病原微生物,在患病奶牛阴道内分离出大肠杆菌(Escherichia coli str.K-12 substr.)、梭杆菌(Fusobacterium nucleatum subsp.)等特定致病菌。研究结果提示,子宫内膜炎奶牛阴道内菌群结构比健康奶牛更为复杂,且无优势菌,阴道菌群结构失衡可能是奶牛发生子宫内膜炎的原因。     

不同益生菌对肉鸡肠道菌群结构的影响

本试验旨在研究益生菌对肉鸡肠道微生态环境的影响,饲养试验选取1日龄的肉公鸡432只,分成4个组,组1饲喂基础饲粮,组2饲喂基础饲粮+地衣芽孢杆菌(≥4×106CFU/g饲粮),组3饲喂基础饲粮+屎肠球菌(≥106CFU/g饲粮),组4饲喂基础饲粮+丁酸梭菌(≥106CFU/g饲粮)。采用PCR-变性梯度凝胶电泳(DGGE)技术对肉鸡肠道内细菌16S r DNA V3区进行菌群多样性分析,利用实时荧光定量PCR(q PCR)技术对肠道菌群数量进行定量分析。PCR-DGGE指纹图谱结果表明:与对照组相比,地衣芽孢杆菌、屎肠球菌和丁酸梭菌均不同程度的影响了肉鸡回肠、空肠及盲肠样品PCR-DGGE指纹图谱的条带数,其中屎肠球菌处理后回肠、空肠样品PCR-DGGE指纹图谱的条带数显著增加(P0.05),其余样品PCR-DGGE指纹图谱的条带数无显著变化(P0.05)。由PCR-DGGE指纹图谱条带明亮度可知:屎肠球菌在回肠食糜中发生了生长繁殖,且促进了乳杆菌生长;地衣芽孢杆菌的添加促进了乳杆菌的生长繁殖,与其产生了协同作用,而抑制了粪肠球菌(C.eutactus)和梭菌(C.irregulare)的生长,二者相互竞争;饲粮中添加丁酸梭菌促进了L.aviaries在空肠及L.versmoldensis在回肠食糜中的生长繁殖,其作用效果比较专一。q PCR结果表明:地衣芽孢杆菌组空肠、回肠及盲肠细菌的菌群数量分别是对照组的1.5倍、1.0倍和1.3倍;屎肠球菌组空肠、回肠及盲肠细菌的菌群数量分别是对照组的4.0倍、6.0倍及0.6倍;丁酸梭菌组空肠、回肠及盲肠细菌的菌群数量分别是对照组的1倍、3.5倍及0.5倍。该研究结果表明地衣芽孢杆菌、屎肠球菌和丁酸梭菌不同程度改变了肉鸡肠道的菌群结构。     

采用聚合酶链式反应-变性梯度凝胶电泳技术分析小熊猫胃肠道菌群的多样性

本试验旨在研究小熊猫胃肠道菌群多样性。采用聚合酶链式反应(PCR)-变性梯度凝胶电泳(DGGE)技术结合条带的克隆测序、聚类分析和主成分分析(PCA)检测小熊猫胃肠道菌群结构及多样性。结果表明:1)PCR-DGGE图谱显示小熊猫胃肠道中有大量菌群,且不同部位的菌群结构存在一定的差异,相邻肠段菌群结构具有一定的相似性。结肠和粪便样品的菌群多样性较高,其次为胃和直肠样品,而空肠和回肠样品菌群多样性较低。2)小熊猫胃肠道菌群PCR-DGGE图谱中测序的条带大多数归为厚壁菌门(Firmicutes)、拟杆菌门(Bacteroides)、变形菌门(Proteobacteria)和疣微菌门(Verrucomicrobia),共性条带主要是未培养拟杆菌门细菌(uncultured Bacteroidetes bacterium)、粪肠球菌(Enterococcus faecalis)、未培养梭状芽孢杆菌(uncultured Clostridium sp.)、乳酸乳球菌(Lactococcus lactis)和食窦魏斯氏菌(Weissella cibaria),其中厚壁菌门为优势菌群;特异性条带主要是丛毛单胞菌(Comamonas sp.)、梭菌属(Clostridium sp.)和Akkermansia。由此可见,小熊猫胃肠道中栖息着大量菌群,且其多样性按照胃肠道由前至后的顺序呈现高-低-高的趋势。     

健康鲁西黄牛消化道和阴道的细菌多样性研究

为了研究健康鲁西黄牛口腔、瘤胃、肠道和阴道的细菌组成及其相似性,分别提取各部位样本细菌的总DNA,特异扩增16Sr DNA的V3~V4高变区,扩增产物进行测序,对测序结果进行Chao1和Shannon Index多样性指数分析、OTUs交叠分析、聚类分析、物种分布波动性分析。结果发现,阴道和肠道的菌群多样性更高且比较相似,而口腔和瘤胃的则相对较低且比较相近;各样本中厚壁菌门、拟杆菌门所占的比例均较高;口腔和阴道的变形菌门较多,瘤胃的纤维杆菌门较多;阴道和肠道厚壁菌门占优势。结果表明:健康鲁西黄牛阴道和肠道细菌相似性很高并且含有相同的优势菌为厚壁菌门。阴道与口腔和瘤胃细菌的相似性很低,口腔、瘤胃和肠道的细菌相似性也很低。     

ST酿酒酵母基因工程菌对大鼠肠道菌群的影响

为了研究ST酿酒酵母基因工程菌对大鼠肠道菌群的影响,试验将90只SPF级SD大鼠随机分为空白对照组、工程菌组及酵母菌组,分别灌服生理盐水、工程菌菌液、酿酒酵母菌菌液,持续21 d后连续3 d灌服大肠杆菌H10407菌液,分别收集灌胃7,14,21天及攻毒后的各组大鼠粪便,提取粪便细菌DNA,利用末端限制性片段长度多态性(T-RFLP)、实时荧光定量PCR检测了ST酿酒酵母基因工程菌对肠道菌群微生物可操作单元(OTU)和肠道5种重要细菌(类杆菌、梭菌、肠球菌、双歧杆菌和乳杆菌)数量的变化,并测定了肠道菌群pH值。结果表明:在灌胃期间,工程菌组及酵母菌组的OTU值和双歧杆菌、梭菌数量极显著高于空白对照组(P0.01),其他细菌数量均不同程度升高。各组pH值均呈现下降趋势,第21天时,工程菌组及酵母菌组pH值极显著低于空白对照组(P0.01)。攻毒产肠毒素大肠杆菌后,工程菌OTU值和类杆菌、乳杆菌、双歧杆菌数量均极显著高于其他两组(P0.01),pH值极显著高于空白对照组(P0.01)。与灌服前相比,工程菌组的OTU值、细菌数量及pH值均变化幅度最小。说明ST酿酒酵母基因工程菌能够改善肠道菌群结构,丰富肠道菌群多态性,降低pH值,增加有益菌群的数量。当动物机体受到产肠毒素大肠杆菌感染时,ST酿酒酵母基因工程菌能够有效降低产肠毒素大肠杆菌对肠道菌群的破坏,发挥预防保护作用,维持肠道内菌群稳定。     

镰形扇头蜱唾液腺、中肠和卵的菌群结构

采用PCR-DGGE技术分析了镰形扇头蜱雌成蜱中肠内容物、唾液腺、虫卵的菌群结构。无菌条件下采集镰形扇头蜱雌成蜱中肠内容物、唾液腺、虫卵,提取细菌总DNA;以通用引物扩增细菌16SrDNA V3区;DGGE电泳,回收、克隆、测定DGGE优势条带。结果表明,饱血和半饱血雌蜱中肠菌群结构相同,中肠内容物、唾液腺和虫卵部分细菌相同;9条明显条带的序列分别与柯克斯体属(Coxiella sp.)、假单胞菌属(Pseudomonas sp.)芽孢杆菌属(Bacillus sp.)、葡萄球菌属(Staphylococcus sp.)、涅斯捷连科菌属(Nesterenkonia)、共生菌(Symbiotic bacteria)和未培养土壤细菌的16SrDNA V3区序列高度相似。分离到2株细菌,为模仿葡萄球菌和蜡样芽孢杆菌。     

肉牛剩余采食量与瘤胃微生物菌群关系北大核心CSCD

剩余采食量(RFI)是肉牛实际采食量与预期采食量之间的差值,是评定肉牛饲料效率的有效指标。肉牛的能量代谢差异在很大程度上可以解释其RFI差异,而肉牛瘤胃中复杂的微生物菌群结构在瘤胃发酵及其能量代谢方面起着重要作用。因此本文主要对最近几年国外采用PCR-变性梯度凝胶电泳(DGGE)、文库克隆测序、实时定量PCR和高通量测序技术研究肉牛RFI表型与瘤胃中的细菌菌群和甲烷菌菌群结构之间的关系所取得的进展进行总结,并介绍RFI的主要预测模型。     

两种山羊瘤胃纤维分解菌16S rDNA序列的体外扩增和鉴定

从山羊瘤胃内容物中提取瘤胃细菌总DNA,以瘤胃中两种主要纤维分解菌为目的菌种,分别依据其16S rDNA序列设计引物,利用PCR技术对其16S rDNA 进行体外扩增,对扩增产物测序后进行同源性分析.结果表明:以提取的瘤胃细菌总DNA为模板,采用PCR技术可成功地从山羊瘤胃内容物中扩增出黄色瘤胃球菌和产琥珀酸丝状杆菌16S rDNA的特异性片段;测序后与GenBank中的序列进行比对,表明黄色瘤胃球菌与原序列(AF104841)的同源性达到99.4%,产琥珀酸丝状杆菌与原序列(AJ505937)的同源性达到94.6%.     

分支杆菌DNA的不同提取方法在PCR反应中的定性评价

采用已报道过的分支杆菌DNA7种不同提取方法分别对标准BCG菌株和结核病鹿肺样本DNA提取后比较并进行聚合酶链反应(PCR)扩增,通过PCR反应对几种DNA提取方法做出定性评价。结果表明:方法5和7有100%临床样本检测率,方法7所得DNA浓度和纯度最高。说明临床样本分支杆菌DNA提取过程中使用物理和化学方法裂解细胞,使用蛋白酶K和氯仿纯化、异丙醇沉淀DNA是十分必要的。     

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。     

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。     

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。     

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。     

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。     

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.