一株猪流行性腹泻病毒的分离鉴定及其ORF3和S基因序列分析

为了探明辽宁省沈阳市某猪场仔猪发生腹泻的病原及其遗传进化特征,试验首先对该猪场发生腹泻的仔猪腹腔进行剖检,记录小肠组织的病理变化;收集病理变化较明显的组织进行切片和H.E.染色,观察并记录结果;取病料后提取病毒核酸,用猪流行性腹泻病毒(Porcine epidemic diarrhea virus, PEDV)、猪传染性胃肠炎病毒(Porcine transmissible gastroenteritis virus, TGEV)、猪丁型冠状病毒(Porcine delta coronavirus, PDCoV)、猪轮状病毒(Porcine rotavirus, PRoV)和猪急性腹泻综合征冠状病毒(Swine acute diarrhea syndrome coronavirus, SADS-CoV)检测引物进行RT-PCR检测;然后进行病毒的分离、致细胞病变效应(CPE)观察、传代、间接免疫荧光试验与效价的测定;最后对病毒的关键基因进行PCR扩增及遗传进化分析。结果表明：腹泻仔猪小肠肠壁变薄、胀满、充满水样内容物,肠系膜呈树枝状充血,肠系膜淋巴结水肿;十二指肠肠绒毛破碎、细胞坏死,...     

猪Delta冠状病毒的研究进展

<正>Delta冠状病毒是冠状病毒科冠状病毒亚科的新成员,可感染禽类和哺乳动物。目前冠状病毒主要分为4个群,包括Alpha冠状病毒、Beta冠状病毒、Gamma冠状病毒和Delta冠状病毒。其中能对猪致病的另外4种病毒,即猪流行性腹泻病毒(PEDV)、猪传染性胃肠炎病毒(TGEV)以及猪呼吸道冠状病毒(PRCV)均属于Alpha冠状病毒。     

犬猫冠状病毒研究进展

犬冠状病毒（canine coronavirus,CCoV）与猫冠状病毒（feline coronavirus,FCoV）同属于冠状病毒科冠状病毒属α属,与其同属的病毒还有猪传染性胃肠炎病毒（porcine transmissible gastroenteritis virus,TGEV）、猪流行性腹泻病毒（porcine epidemic diarrhea virus,PEDV）等。遗传进化分析表明,该种属不同基因型病毒通过基因重组能产生新型变异毒株,为疾病的诊断与防控造成了很大的阻碍。β属冠状病毒包括牛冠状病毒（bovine coronavirus,BCoV）、犬呼吸道冠状病毒（canine respiratory coronavirus,CRCoV）、严重急性呼吸综合征冠状病毒（severe acute respiratory syndrome coronavirus,SARS-CoV）等,其中CRCoV与BCoV同源性较高,该类病毒与α属冠状病毒在基因组结构、致病机制、感染症状等方面差异较大。CCoV与FCoV在全球范围内广泛传播,具有发病率高、死亡率低的特点。由于RNA病毒本身的特点和环境选择压力的影响,这两种病毒不断变异进化,新的强致病力毒株相继出现。经FCoV基因突变演化而来的猫传染性腹膜炎病毒（feline infectious peritonitis virus,FIPV）毒力大大增强,病毒基因组中某些特异性的点突变使得针对宿主的细胞嗜性发生改变,该病毒的致病机制主要依赖于病毒感染后诱导机体产生的抗体依赖性增强作用（ADE）。针对犬猫冠状病毒的流行病学调查及防控不能仅依赖于疫苗免疫单一因素,还应综合考虑病毒毒力、环境条件、宠物自身免疫抵抗力状态等。针对犬猫冠状病毒的诊断应根据临床症状,结合常规血液学检查、血清生化检查和实验室诊断技术来进行全面的鉴定,防止出现假阳性及假阴性结果。     

猪传染性胃肠炎病毒感染IPEC-J2细胞模型的建立

<正>猪传染性胃肠炎病毒(Transmissible gastroenteritis virus,TGEV)属于冠状病毒科冠状病毒属成员,是一种多形性有囊膜病毒,可导致猪传染性胃肠炎(tansmissible gastroenteritisof swine,TGE),该病是一种高度接触性肠道传染病,主要引起猪的严重呕吐、腹泻和脱水[1],对新生仔猪具有高度致死率,死亡率可达100%。TGEV能在猪源细胞系上增殖,其中较     

包头地区猪病毒性腹泻的流行病学调查

正猪病毒性腹泻主要是由猪流行性腹泻病毒(Porcine epidemic virus,PEDV)、猪传染性胃肠炎病毒(Transmissible gastroenteritis coronavirus,TGEV)、猪轮状病毒(Rotavirus,RV)这三种病毒单独或混合感染而引起猪的一种急性肠道传染病[1],临床上以厌食、呕吐、水样腹泻为主要特征。该病一年四季均可发     

PEDV在全球范围内的流行与传播

正近些年,猪流行性腹泻病毒(Porcine Epidemic Diarrhoea virus,PEDV)给亚洲和北美的养猪业带来了灾难性的后果。不过,2015年在欧洲出现的PEDV毒株的毒力似乎要弱一些。本文将介绍PEDV在全球范围内的流行与传播。一、病原猪流行性腹泻(PED)是由冠状病毒(Coronavirus)引起的一种重要肠道疾病。冠状病毒科可以分为α冠状病毒(Alpha coronavirus)、β冠状病毒(Beta coronavirus)、γ冠状     

猪冠状病毒的起源与遗传演化

冠状病毒变异率高,宿主广泛,主要感染哺乳动物和禽类,严重威胁公共卫生安全与养殖业发展.生猪养殖业中,冠状病毒也是危害猪只健康的重要病原.本研究对4种代表性猪冠状病毒:猪传染性胃肠炎病毒(transmissible gastroenteritis virus,TGEV)、猪流行性腹泻病毒(porcine epidemic...     

猪流行性腹泻疫苗的研究

猪流行性腹泻(porcine epidemic diarrhea,PED)是由尼多目(Nidovirales)、冠状病毒科(Coronaviridae)、冠状病毒属(Coronavirus)α-冠状病毒中的猪流行性腹泻病毒(porcine epidemic d iarrhea virus,PEDV)引起的猪的一种急性、高度传染性的肠道疾病,该病以急性肠炎、呕吐、水样腹泻和脱水为主要特征.     

一例猫传染性腹膜炎的诊断

猫传染性腹膜炎(Feline infectious peritonitis, FIP)是一种由猫冠状病毒(Feline coronavirus, FCoV)突变而引起的一种渐进性、致死性传染病^[1],该病死亡率达95%以上。猫传染性腹膜炎病毒(Feline infectious peritonities virus, FIPV)能够在巨噬细胞中高效复制,是导致家猫死亡的主要病毒之一^[2]。     

广东地区2016-2017年规模化猪场腹泻病原调查分析

为了解广东地区导致猪群腹泻病原的流行状况,对广东省部分地区的猪场进行猪群腹泻的流行病学调查,共采集腹泻样品273份,采用PCR和RT-PCR的方法检测能够造成猪群腹泻的病原,包括猪流行性腹泻病毒(PEDV),猪轮状病毒(PoRV),猪传染性胃肠炎病毒(TGEV),以及近年开始流行的猪德尔塔冠状病毒(Porcine Deltacoronavirus,PDCoV),猪库布病毒(Porcine Kobuvirus,PKoV),猪博卡病毒(Porcine Bocavirus,PBoV),猪萨佩罗病毒(Porcine Sapelovirus,PSV)。检测结果显示,PEDV仍然是导致猪群腹泻的主要病原,而TGEV没有检测到。尤为突出的是PKV仅次于PEDV的高阳性率,因此其在猪群腹泻中的作用值得进一步探索。     

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.     

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…     

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.