Shiga toxin-producing Escherichia coli O157:H7 from extensive cattle of the fighting bulls breed

Shiga toxin-producing Escherichia coli (STEC) O157:H7 represents a major public health concern worldwide, with cattle recognized as their main natural reservoir. The aim of this work was to determine the prevalence and the pheno-genotypic characteristics of STEC O157:H7 in a herd with 268 cattle of the fighting bulls breed (De Lidia breed) managed under extensive conditions in the South-West of Spain. Rectal-anal swabs of all animals were collected and examined for STEC O157:H7 by performing an immunomagnetic concentration and separation procedure combined with PCR, and the resulting isolates were characterized by both phenotypic and genotypic methods. Overall, STEC O157:H7 was isolated from seven animals (2.6%) in the herd. The PCR procedure indicated that all seven isolates displayed stx₂, eae-γ1, ehxA, O157 rfbE, and fliCh7 genes. They belonged to phage types 4 (one isolate) and 42 (two isolates), and four isolates reacted with typing phages but did not conform to a recognized pattern. Among the seven isolates there were five indistinguishable PFGE patterns and other two which differed only in ?2 restriction fragments, supporting the existence of horizontal transmission among animals in the herd. The present study demonstrates that cattle managed under extensive conditions in Spain can excrete STEC O157:H7 with their faeces. To our knowledge this is the first isolation of this pathogen from De Lidia cattle.     

Detection of all Chlamydophila and Chlamydia spp. of veterinary interest using species-specific real-time PCR assays

The aim of the present study was to analyse the occurrence of chlamydiae in several mammalian host species. Clinical samples that previously tested positive in a Chlamydiaceae-specific real-time PCR were retested using six species-specific real-time PCR assays to identify the chlamydial species involved. Chlamydophila (Cp.) abortus was the agent most frequently found in cattle, sheep, horses, goats, and pigs. Detection in cattle of Cp. psittaci (11% of samples) and Chlamydia (C.) suis (9%), as well as Cp. psittaci in a goat sample was somewhat unexpected. DNA of two different chlamydiae was identified in 56 (12.7%) of 440 samples tested. Cp. felis was the predominant species found in cats, while in guinea pigs and rabbits only Cp. caviae was detected. Interestingly, the latter two pathogens were also identified in samples from dogs. The data show that mixed chlamydial infections are not rare and suggest an extended host range of individual species.     

流行性乙型脑炎病毒E蛋白单克隆抗体的制备与鉴定

流行性乙型脑炎病毒(JEV)是一种严重危害人畜健康的虫媒病毒。表面囊膜蛋白(E蛋白)是该病毒的主要结构蛋白。本研究利用原核表达的乙型脑炎病毒SA14-14-2株结构蛋白E蛋白作为免疫原,免疫6周龄BALB/c小鼠,采用淋巴细胞杂交瘤技术进行融合,经有限稀释法获得1株特异性针对JEV E蛋白的杂交瘤细胞,命名为5D4,经测定5D4单抗亚类属于IgG2a,轻链为κ链。经Western blot证实所得杂交瘤细胞分泌的抗体可特异地与JEV E蛋白结合。结果表明,所制备的抗JEV E蛋白的单抗对病原检测具有很高的特异性,为JEV准确快速的病原诊断和JEV感染相关的基础性研究提供了物质基础。     

锰致鸡睾丸DNA-蛋白质交联的研究

目的:探讨锰致鸡睾丸DNA-蛋白质交联效应。方法:在饲料中添加500、800、1 700 mg/kg MnCl2建立亚慢性锰中毒模型,分别在试验30 d、60 d、90 d剖杀鸡只取睾丸组织,进行DPC(DNA-蛋白质交联)的检测,并在90 d进行生精细胞的凋亡检测。结果:与对照组相比,各染毒组睾丸组织DPC系数显著增大,凋亡指数升高。结论:锰能使睾丸组织DPC系数增大,生精细胞凋亡指数升高,导致DNA损伤,进而引起细胞凋亡。     

公共图书馆应对金融危机应有所作为

在金融危机的冲击下,我国大量农民工失业返乡。在引导和促进农民工自我发展,使其成为市场经济中有竞争力的主体方面,公共图书馆应有所作为。对农民工进行培训,让农民工有一技之长,进一步提高农民工素质,无论是对于农民工自主创业还是再就业都起着至关重要的作用。     

浅谈西宁市城市绿地地被植物应用

西宁市城市绿地地被植物配置在不断吸取国内外优良植物材料和先进植物配置手法的基础上,积极挖掘乡土树种和适生树种,不断地丰富了城市地被植物材料,提高了地被植物配置手法,地被类型从单一的草坪地被逐步发展成为疏林草地地被、缀花草坪地被、木本植物地被等配置类型,增加了城市地被植物种类,丰富了色相和季相变化,提高了绿地景观效果,逐步形成具有高原古城特色的城市绿地地被植物类型。     

纳米载铜蒙脱石对生长肥育猪生产性能

摘要：试验旨在研究日粮中添加纳米载铜蒙脱石对生长育肥猪生产性能及血液生化指标的影响。选取72头健康“杜×大×长”三元杂交断奶仔猪,随机分为3组,每组3个重复,每个重复8头(公母各半)。分别饲喂基础日粮（对照组）、基础日粮+20 mg/kg泰乐菌素+100 mg/kg磺胺二甲基嘧啶(SM2)（试验Ⅰ组）和基础日粮+1500 mg/kg纳米载铜蒙脱石（MMT-Cu）（试验Ⅱ组）。比较研究MMT-Cu和泰乐菌素＋磺胺二甲基嘧啶对生长肥育猪生产性能及血液生化指标的影响。结果表明,与对照组和试验Ⅰ组相比,试验Ⅱ组料重比、血清ALB、SUN、Ch、TP含量极显著下降(P<0.01);血钙含量、GTP活性极显著提高（P<0.01）;TP和GLU含量显著下降 (P<0.05)。因此,纳米载铜蒙脱石提高了生长肥育猪的料重比,并对血清中ALB 、Ca、GPT、SUN、TG、Ch、TP、GLU均产生不同程度的影响。     

猪圆环病毒病的特点

在最近几年中,养猪业遇到了越来越多的疾病,药物使用量显著增加,也使养殖场主、养殖户和兽医师感到非常的困惑。目前已经证实,猪圆环病毒病(Porcine Circovirus diaease,PCVD)在世界上广泛存在。可以引起断奶仔猪助多系统衰竭综合征(PMWS)、猪皮炎-肾病综合征(Porcine dermatitis and nephropathy syndrome,PDNS)和猪呼吸系统疾病症候群,给养猪业造成了巨大的经济损失。同时这一疾病常常与其他病毒或细菌性疾病发生混合感染,给猪病的防控带来了极大的困难。本文就猪圆环病毒病的某些特点作一简要论述。     

紫丁香蘑菌丝体生物学特性研究初报

为探索紫丁香蘑最佳栽培条件,分别从温度、pH值、碳源和氮源4个方面,研究了紫丁香蘑菌丝体的部分生物学特性,结果表明:其生长所需温度偏低,最适温度为16～22℃;最适pH值为4.0～7.0,适宜于在酸性至中性环境中生长;对稻草的分解能力最强,可将其作为主要碳源;以(NH4)2SO4为氮源时生长很好,可在栽培材料中加入适量(NH4)2SO4作为氮源。     

Prd29A:PaDREB2植物表达载体的构建及转化新疆杨的研究

PaDREB2是从银新杨(Populus alba×P.albavar.pyramidalis)中克隆得到的DREB类转录因子,该研究将逆境诱导型rd29A基因的启动子和PaDREB2构建到植物表达载体pCAMBIA1301上,并以新疆杨(Populus albavar.pyramidalis)试管苗的叶片外植体为受体,利用根癌农杆菌介导的方法进行遗传转化。筛选得到110株潮霉素抗性植株,经PCR检测,其中25株抗性植株存在目的基因Prd29A:PaDREB2。