防治禽大肠杆菌病的安全用药技术

为在防治禽大肠杆菌病时能制订合理的安全用药方案,减少药物残留和防止耐药菌株的出现,本文从一般性措施、中西药物的防治、微生态制剂的应用和免疫预防接种四方面讨论了禽大肠杆菌病的综合防制技术。     

禽大肠杆菌病的免疫防制研究概况

禽大肠杆菌病的免疫防制研究概况赵香汝＊（中国农业大学动物医学院，北京海淀１０００９４）禽大肠杆菌病是由大肠杆菌引起的主要的细菌性传染病。此病在世界范围内存在，严重地影响了养禽业的发展，在我国多数鸡场无论是雏鸡还是成年鸡均可发生本病。张炳仁（１９９６）...     

禽大肠杆菌研究进展

近年来,禽类的集约化、规模化养殖越来越普遍,与此同时,禽类大肠杆菌病的感染率和死亡率也逐年上升,该病已成为危害养禽业的主要细菌性传染病之一。本文就禽大肠杆菌病病原的现状、耐药机制以及防控方法等方面进行了介绍,以期为禽大肠杆菌病的防治提供理论依据。     

禽大肠杆菌病的诊断及防制

禽大肠杆菌病是由某些致病性血清型大肠杆菌引起的禽类不同类型疾病的总称。 1病原 本病的病原属肠道杆菌科埃希氏菌属的大肠埃希氏杆菌,简称大肠杆菌。本菌为两端钝圆的中等大杆菌,宽约0．6微米,长2-3微米,有时近似球形。单独散在,不形成长链条。多数菌株有5-8根鞭毛,运动活泼。周身有菌毛,一般还具有可见的荚膜。对普通碱性染料着色良好,有时两端着色较深,革兰氏阴性。     

中草药防治禽大肠杆菌病的研究进展

以大肠杆菌的耐药机制和中药药理为基础,从中草药对禽大肠杆菌R质粒消除及对禽大肠杆菌病防治效果角度,综述了近年来中草药防治禽大肠杆菌病的研究进展。     

禽大肠杆菌病用药指引

禽大肠杆菌一直困扰着养禽业，为达到有效控制该病对养禽业的危害，笔者将防治分流予以介绍，供业内参考。     

禽大肠杆菌病专栏

<正> 一、发病情况贾某引进1日龄雏鹅1800只,按正常的免疫程序进行免疫。5天后鸡只开始发病,临床表现发病急,死亡率高,发病率20%左右。二、临床症状主述:病鹅精神委顿、羽毛蓬乱、食欲减退、拉黄稀粪,而且有的粪便中带有丝状物;部分鹅腿发软,站立不稳,死后口吐黏液;个别歪脖、呼噜,但未发现有肿头、流眼泪的。三、病理变化腺胃乳头充血、出血,盲肠扁桃体肿大、出血,其他脏器未见异常变化。四、实验室诊断1.无菌采取病死鹅的肝脏及脑组织,分别接种于普通琼脂平板、麦康凯琼脂及伊红美蓝琼脂平板,经37℃24小时培养,各种培养基上均有菌落形成。在营养琼脂平板上形成中等大小。直径1～3毫     

益生菌对猪大肠杆菌病防治作用的研究进展

动物大肠杆菌病是危害我国畜禽养殖行业的重要疾病,基于猪大肠杆菌病的病原学和流行特点,从益生菌的作用机理及其活性的限制性因素出发,以乳酸杆菌、双歧杆菌、肠球菌、酵母菌等常用益生菌的最新研究进展为根据,分析探索益生菌制剂代替抗生素在防治仔猪疾病中应用的可行性,显示了益生菌的潜力和优势,更好地推动畜禽养殖业的发展。     

猪大肠杆菌病及其防治

大肠杆菌在肠道内属于正常菌属,但也可致病.猪大肠杆菌病在我国的较多猪场都有发生,主要以三种形式存在：即仔猪黄痢、仔猪白痢和水肿病.     

浅谈禽大肠杆菌病常见混合感染的类型及诊疗

近年来,家禽大肠杆菌病在大多数养殖场中均广泛流行,发病率和死亡率居高不下,很多地方已成暴发流行的趋势,严重威胁着养禽业的发展。在临床上,许多疾病可导致大肠杆菌病的继发或混合感染,如鸡沙门氏菌病、霉形体病、传染性鼻炎、传染性支气管、喉气管炎、     

禽白血病病毒研究进展

禽白血病是由禽白血病病毒 ( avian lekosis virus,ALV)引起的以造血细胞恶性增生为主的一类传染病 ,包括淋巴细胞性白血病 ,成红细胞性白血病 ,成髓细胞白血病和髓细胞样白血病 ,对养禽业危害最大的是禽淋巴细胞性白血病 ( lymphoid leukosis,LL)。自 1 90 8年首次报道并分离到 ALV以来 ,世界上许多国家都有该病的流行和发生 ,其垂直和水平传播引起临床和亚临床感染而造成较大的经济损失 [1 ,2 ]。近年来 ,随着分子生物学技术的广泛应用 ,在该病毒的囊膜基因、病毒受体、致病机理、内源性白血病病毒和培育 ALV抗性鸡等方面取得了不少…     

Comparison of several challenge models for studies in avian colibacillosis

In previous studies, the embryo lethality assay (ELA) discriminated between virulent and avirulent avian Escherichia coli isolates, and also proved to be highly correlated with mortality and morbidity results of the intravenous (IV) challenge model. In the current study, the same 20 avian E. coli isolates were used in subcutaneous (subQ) and intratracheal (IT) chicken challenge models in order to determine whether the results from the prior ELA challenges and/or the IV challenge model correlate with these models. The correlation observed between the two previous ELA trials and the combined mortality/morbidity percentages of the subQ challenge model were r = 0.792, P > 0.0001 for the first ELA trial and r = 0.738, P = 0.0002 for the second ELA trial. The IV challenge results were more highly correlated with the subQ challenge results (mortality/morbidity comparison, r = 0.894, P < 0.0001). The IV challenge mortality results were slightly correlated (r = 0.4810, P=0.0319) with the IT challenge results. Several of the isolates differed in their ability to produce mortality and/or morbidity with the different challenge models. The mortality/morbidity results of the IV and subQ challenges and the mortality results of the ELA were all positively correlated with the ability of an E. coli isolate to produce Colicin V (ColV) (r = 0.7131, P = 0.0004). The IT mortality results were slightly correlated with the production of ColV (r = 0.455, P = 0.049). The IT challenge results were only slightly correlated with resulting IV mortality and ColV production. Previous results indicate that the ELA correlates extremely well with the IV challenge model. The current study demonstrates that ELA also correlates well with the subQ challenge model. Overall, the conclusion of this study is that the ELA, IV, and subQ challenge models similarly demonstrate the ability to discriminate between virulent and avirulent avian E. coli isolates.     

Recombinant Iss as a potential vaccine for avian colibacillosis

Avian pathogenic Escherichia coli (APEC) cause colibacillosis, a disease which is responsible for significant losses in poultry. Control of colibacillosis is problematic due to the restricted availability of relevant antimicrobial agents and to the frequent failure of vaccines to protect against the diverse range of APEC serogroups causing disease in birds. Previously, we reported that the increased serum survival gene (iss) is strongly associated with APEC strains, but not with fecal commensal E. coli in birds, making iss and the outer membrane protein it encodes (Iss) candidate targets for colibacillosis control procedures. Preliminary studies in birds showed that their immunization with Iss fusion proteins protected against challenge with two of the more-commonly occurring APEC serogroups (O2 and O78). Here, the potential of an Iss-based vaccine was further examined by assessing its effectiveness against an additional and widely occurring APEC serogroup (O1) and its ability to evoke both a serum and mucosal antibody response in immunized birds. In addition, tissues of selected birds were subjected to histopathologic examination in an effort to better characterize the protective response afforded by immunization with this vaccine. Iss fusion proteins were administered intramuscularly to four groups of 2-wk-old broiler chickens. At 2 wk postimmunization, chickens were challenged with APEC strains of the O1, O2, or O78 serogroups. One week after challenge, chickens were euthanatized, necropsied, any lesions consistent with colibacillosis were scored, and tissues from these birds were taken aseptically. Sera were collected pre-immunization, postimmunization, and post-challenge, and antibody titers to Iss were determined by enzyme-linked immunosorbent assay (ELISA). Also, air sac washings were collected to determine the mucosal antibody response to Iss by ELISA. During the observation period following challenge, 3/12 nonimmunized chickens, 1/12 chickens immunized with 10 microg of GST-Iss, and 1/12 chickens immunized with 50 microg of GST-Iss died when challenged with the O78 strain. No other deaths occurred. Immunized chickens produced a serum and mucosal antibody response to Iss and had significantly lower lesion scores than nonimmunized chickens following challenge, regardless of the challenge strain. This study expands on our previous report of the value of Iss as an immunoprotective antigen and demonstrates that immunization with Iss can provide significant protection of chickens against challenge with three different E. coli strains.     

基因芯片检测技术在禽类病原检测方面的研究进展

基因芯片是继PCR后发展起来的一项快速、特异性好、敏感性强及高通量等优点的自动化基因检测技术,被广泛地应用于药物筛选、基因研究和疾病诊断检测等方面。随着病原不断发生基因重组,变异等现象,禽类病毒不断逃避免疫保护导致了强毒株的出现。传统的芯片检测方法虽然能够实现病毒的检测,然而昂贵的仪器设备和较长的检测时间严重阻碍了芯片技术在实际生产中的应用。一种低成本、时间短、快速有效的新的基因芯片技术的开发和应用是解决当前禽业产业发展的必要手段。基因芯片检测技术方法的改良及应用已成为目前疾病诊断的研究热点。本研究主要综述了基因芯片检测技术在禽类疾病检测方面的发展现状,并对今后该技术的发展方向和重点作了展望。     

中草药在兔大肠杆菌病防治中的应用

兔大肠杆菌病又名黏液性肠炎,是由某些血清型的大肠杆菌及其毒素引起的死亡率很高的一种兔急性肠道传染病。该病主要通过消化道传播,病原广泛存在于自然界中,是兔体肠道内的常在菌。此病一年四季都可发生,1-4月龄幼兔的发病率和死亡率最高,成年兔很少发病。家兔往往因食入被污染的饲料、饮水而被感染。防治多采用抗菌药物,但由于抗菌药物的不合理应用,     

肉用仔鸡大肠杆菌病的诊断与防治

肉用仔鸡大肠杆菌病是由大肠埃希氏菌的某些血清型引起的一类疾病的总称。近年来随着集约化养鸡的迅速发展,该病的流行日趋严重,使患病的鸡群生长发育受阻,饲料转化率下降、治疗费用增加、死淘率及屠宰废弃率增加等等,给养鸡户造成了极大的经济损失。该病已成为养鸡业危害大,造     

中西兽药防治猪大肠杆菌病的效果研究

目的:探讨中西兽药在猪大肠杆菌病防治中的应用效果。方法:选取60头健康仔猪,随机分为三组,各组20头,分别设定为中西结合组(苦参止痢颗粒和硫酸庆大霉素)、复方中草药组(苦参止痢颗粒)、抗生素组(硫酸庆大霉素),给予相应的药物干预,观察用药7 d后三组患猪粪便的大肠杆菌数变化、猪肠道病理变化以及临床治疗效果。结果:中西结合组干预后大肠杆菌数显著低于复方中草药组、抗生素组(P<0.05);中西结合组治疗7 d后肠道病理变化有了明显改善,而复方中草药组、抗生素组肠道仍然存在一定的病变特征;中西结合组治疗的总有效率高于复方中草药组、抗生素组(P<0.05)。结论:中西兽药结合用药可较好地实现对猪大肠杆菌病的治疗,值得推广。