玉米黑穗病发生原因和防治措施

1发生原因 玉米丝黑穗病是以土壤传播为主,苗期侵染的病害。病原菌为丝轴团散黑粉菌,以冬孢子散落在土壤中,混入粪肥里或粘附在种子表面越冬。冬孢子在土壤中能存活3年,土壤带菌和混有病残组织的粪肥是其主要侵染源。种子表面带菌虽可传病,但侵染率极低,是远距离传播的侵染源。玉米丝黑穗病发病轻重取决于品种的抗病性和土壤中菌源数量以及播种和出苗期环境因素的影响。     

鸡白痢病的诊断与防治

1诊断要点1.1流行特点本病是一年四季均可发生的一种卵传性疾病,种鸡场如被本菌所污染,种鸡中就有一定比例的病鸡或带菌鸡,这些鸡所产的种蛋同样有一定比例是带菌的,在孵化过程中会造成胚胎死亡,孵出弱雏、病雏。病鸡和带菌鸡是本病的主要传染来源,主要通过消化道     

牛巴氏杆菌病及其防治措施

1流行病学牛巴氏杆菌病主要发生于各种年龄的牛,水牛易感性更高。病畜和带菌动物是该病的传染源,尤其带菌动物,包括健康带菌和病愈后带菌。该病可通过直接接触和间接接触传播,如水牛往往因饮用病牛     

肉鸭感染沙门氏菌的诊断与治疗

肉鸭沙门氏菌病是指由肠杆科沙门氏菌属中的一种或多种细菌所引起的禽类疾病,主要为禽伤寒和禽副伤寒.禽沙门氏菌病可以垂直传播也可以水平传播.鸭群病鸭、带菌鸭是主要的传染源,主要经呼吸道或消化道感染健康鸭群,但最常见的是通过带菌蛋传播,成年带菌鸭产出带菌蛋,再孵化出带菌雏鸭,周而复始代代相传,给养鸭业造成严重经济损失.     

环颈雉雏鸡伤寒的诊断与治疗

<正>雏鸡伤寒是由鸡沙门菌引起的一种急性败血性传染病,病鸡和带菌鸡是本病的主要传染源,被污染的种蛋也能引起传染,雏鸡感染本病多由于种蛋带菌,在孵化器内相互传染,也可以在孵化后与病鸡或带菌鸡直接或间接接触发生感染,也可通过饲养人员、饲料袋等机械地传播本病。本市9608     

浅谈蛋鸡常见腹泻病及其综合防治

<正>产蛋鸡腹泻病主要有:大肠杆菌病、沙门氏菌病、巴氏杆菌病、坏死性肠炎、新城疫和球虫病,下面对这几种病的临床症状、剖检病变及综合防治进行介绍:1常见腹泻病1.1大肠杆菌病病原为致病性大肠杆菌;本病一年四季均可发生,但主要以阴雨潮湿的夏季为主;大肠杆菌病鸡和带菌鸡是主要传染源,产蛋鸡通过接触被大肠杆菌病鸡或带菌鸡分泌物污染的饲料、饮水用具经消化道传染,也通过空气中携带     

鸡支原体的诊治

笔者在兽医临床上曾多次处理过鸡支原体病例 ,现就该病的诊断和防制介绍如下。1　流行特点各日龄鸡均可感染本病 ,以 1～ 2月龄雏鸡发生率较高 ,一年四季均可发生 ,以寒冷季节、高密度饲养、通风不良的肉仔鸡最易发生。隐性带菌鸡、病鸡是主要传染源 ,可通过病鸡咳嗽、打喷嚏经呼吸道感染 ,或经饲料和引水感染。鸡支原体病是一种经卵传递的疾病 ,病鸡、带菌鸡所产蛋含支原体 ,用被其污染的种蛋孵化的鸡雏被感染 ,导致大多数鸡群带菌现象极普遍。鸡支原体病的发生有明显的诱因 ,如饲养密度大、通风不良、氨气浓度过大或温差比较大、料中缺乏…     

一例羊沙门氏菌病的诊治报告

羊沙门氏菌病主要是由鼠伤寒沙门氏菌、羊流产沙门氏菌引起羊的一种传染病,以病羊发生下痢、孕羊发生流产为主要临床特征。羊易感,不分品种,性别、年龄或断乳龄或断乳不久的羊最易感;病羊和隐性感染羊或健康带菌羊为主要传染源;本病一年四季均可发生,育成羊常于夏季和早秋发病,孕羊主要在晚冬、早春季节发生。     

五种牧草及三种草坪草种子寄藏真菌检测初探

采用PDA平皿法和滤纸法检测了市售5个牧草品种和3个草坪草品种种子样品寄藏真菌的情况,并就分离获得的真菌对种子出苗及幼苗生长的影响进行了初步研究.结果表明,供试种子样品带菌率为0～70.5%,分离获得的35个真菌分离物大多属于镰刀菌(Fusarium spp.)、链格孢菌(Alternaria spp.)、蠕孢菌(Helminthosporium spp.)、小核菌(Sclerotium sp.)、匍柄霉菌(Stemphylium spp.)和曲霉菌(Aspergillus spp.).供试样品中假俭草和波多马各(鸭茅)种子带菌率较高,在PDA平皿检测中其未经表面消毒处理的种子带菌率分别为48.4%和70.5%,表面消毒处理种子带菌率分别为40.8%和28.8%,分离获得的种子寄藏真菌对假俭草和波多马各种子出苗及幼苗生长的影响较小.圣地亚哥(南苜蓿)和菊苣种子带菌率较低,但分离获得的真菌对其种子出苗和幼苗生长的影响较大.以镰刀菌与匍柄霉菌接种过的南苜蓿种子出苗率分别比未经表面消毒且未接种真菌的对照低44.0%和21.7%,出苗后的病苗率分别为22.7%和29.7%;以链格孢菌与曲霉菌接种过的菊苣种子的出苗率分别比未经表面消毒且未接种真菌的对照低22.0%和27.5%,出苗后的病苗率分别为2.3%和29.3%.     

犊牛副伤寒病的诊治及预防

牛副伤寒病是由牛沙门氏菌引起的以下痢为主要症状的疾病,是一种主要侵害10~30日龄新生幼犊的传染病。犊牛通常是采食了病牛、带菌牛粪尿污染的饲料、饮水等而感染发病,带菌母牛有时还可通过乳汁排出病菌感染犊牛。未喂初乳、乳汁不良、断奶过早、寒冷潮湿以及寄生虫侵害等因素可促使本病发生。犊牛副伤寒病往往呈流行性发生,成年牛呈散发。     

苜蓿新品种特异性、一致性和稳定性测试指南初报

在系统查阅国内外文献、广泛收集苜蓿种质、连续5年田间性状评价和广泛征求专家意见基础上，首次编制了我国苜蓿特异性、一致性和稳定性（DUS）测试指南。指南在主要形式与内容上，与国际植物新品种保护联盟（UPOV）的苜蓿测试指南相协调，包括测试的总体技术要求、性状表、性状解释和技术问卷等4部分；在性状与标样品种确定上既参照了UPOV及一些发达国家的测试指南，又考虑了我国苜蓿育种的特点和方向。     

噬菌体制剂治疗细菌感染的研究进展

噬菌体是一类细菌依赖性病毒,可有效地治疗细菌性感染,尤其是大量耐药菌株的出现使抗生素对细菌病的治疗越来越棘手,噬菌体疗法将对细菌病的控制起更加积极的作用。作者就噬菌体抗菌机理、治疗优势、噬菌体治疗细菌感染的研究及噬菌体裂解素的研究进展进行综述。     

几种燕麦引种栽培及品种比较试验研究

1 997～ 1 999年 ,在西宁及果洛不同地区的引种栽培和品种比较试验结果表明 :6种燕麦在西宁地区种子均成熟良好。永久 0 0 1表现早熟 ,YTA、青海 444中熟 ,MELYS、LENA、NEON晚熟 ;MELYS、LENA和青海 444籽实产量较高 ,其总穗数、穗粒数、千粒重综合性状较好 ,产量结构合理 ,具有高产性能 ;北欧引进的燕麦品种表现为植株高大、生育期长、籽实产量高的特性 ;LENA和永久 0 0 1干草和蛋白质产量均较高 ;北欧引进的晚熟品种适于相对低海拔地区种植 ;MELYS、YTA及永久 473的饲草品质优于其它品种     

12份苜蓿农艺性状的主成分及聚类分析

对12份苜蓿种质资源进行全年株高、茎叶比、分枝数、主枝侧枝数、主枝节间数、鲜草产量等6个农艺性状的主成分分析,选出累计贡献率84.141%的前3个主成分;在此基础上对12份苜蓿材料进行系统聚类分析,在欧式水平上可将其聚为3大类,第1大类在江淮地区表现为产量高,全年高度、分枝数、主枝侧枝数均高于其他材料,比较适宜南方的气...     

草地早熟禾新品种特异性、一致性和稳定性测试指南初报

在系统调研国内外文献,广泛收集草地早熟禾种质,连续2年温室幼苗性状评估,连续3年田间性状评价和广泛征求专家意见的基础上,首次编制了我国草地早熟禾特异性、一致性和稳定性(DUS)测试指南。指南在形式与主要内容上,与国际植物新品种保护联盟(UPOV)的草地早熟禾测试指南相协调,包括测试的总体技术要求、性状表、性状解释和技术问卷4部分;在性状与标样品种确定上主要参照了UPOV和日本的测试指南。     

Responsible antimicrobial use in critically ill adult horses

Due to increasing antimicrobial resistance, pressure on veterinarians is mounting to adhere to responsible use of antimicrobial drugs. Antimicrobials are frequently included in the treatment of systemically ill horses due to the strong likelihood of an infection and the innate difficulties in differentiating systemic inflammation secondary to noninfectious from infectious causes. In light of increasing antimicrobial drug resistance and the potential negative impact of antimicrobials on equine patients, every attempt should be made to identify noninfectious disease, choose first-line antimicrobials and discontinue treatment as soon as possible. In most cases, a short duration of antimicrobial therapy ranging from a single dose (e.g. preoperatively) to 24–72 h might be sufficient with long-term treatment being rarely required. This article aims to provide practical guidelines for antimicrobial drug usage in critically ill adult horses by describing ancillary diagnostic aids that can help establishing whether or not an infection is present, discussing commonly encountered pathogens and their typical antimicrobial drug sensitivity patterns, and providing some guidance how to safely shorten the duration of antimicrobial therapy.     

Gastrointestinal nematode infection in sheep--a review of the alternatives to anthelmintics in parasite control

Efforts to curb production losses caused by nematode parasitism in sheep have led to the development of a number of control methods to complement or replace anthelmintics. The need for alternative control measures stems from the emergence of anthelmintic-resistant parasitic nematodes with reports of multi-class resistance to these drugs now emerging. A number of these control methods such as predacious microfungi, protein supplementation, plant extracts in feed and vaccines have demonstrated potential to control infection but require development and examination under natural conditions. Breeding for natural resistance to nematode infection has already shown success in controlling the disease under natural conditions. Selection for resistance is currently based on fecal egg count measurements but identification of genetic indicators of resistance will provide a more efficient method of selection. Current quantitative trait loci for nematode resistance include the MHC genes, interferon gamma gene, IgE gene and microsatellites on chromosome 1, 5 and 6. This paper reviews the current alternatives to anthelmintics to control infection, with an emphasis on breeding for host resistance and identification of genetic indicators of resistance.     

禽致病性大肠杆菌实验感染模型研究进展

禽致病性大肠杆菌（avian pathogenic Escherichia coli,APEC）是导致不同日龄禽类局部和全身感染的重要病原菌,也是人肠外致病性大肠杆菌（extraintestinal pathogenic Escherichia coli,ExPEC）毒力基因的重要储存宿主或来源。为深入理解APEC的感染过程、致病机理、宿主免疫应答及遗传抵抗机制、评估药物和疫苗防治效果,研究者通过不同途径建立了多种评估APEC毒力的实验感染模型。根据所涉及的系统不同可分为呼吸系统、脉管系统、肌肉系统、皮肤系统、生殖系统、消化系统及鸡胚系统等。此外,尚有小鼠与大鼠感染试验及组织培养细胞和外植块感染试验等。作者重点介绍了不同APEC实验感染模型的建立、致病机制、宿主应答及应用。     

Advances on the Experimental Infectious Models of Avian Pathologenic Escherichia coli

Avian pathogenic Escherichia coli(APEC) is an important pathogen that causes localized and systemic infection in avian species of all ages.It is also an important reservoir or source of virulence genes of human extraintestinal pathogenic Escherichia coli (ExPEC).In order to understand deeply the infection progresses,pathogenesis,host immune responses and genetic resistance mechanism of APEC,and evaluate the efficacy of drugs and vaccines,several experimental infection models were established to evaluate the virulence of APEC through different approaches.According to the different systems involved,it can be divided into respiratory system,vascular system,musculoskeletal system,dermatological system,reproductive system,gastrointestinal system and chicken embryo system.In addition,there are infection experiments in mice and rats,tissue culture cells and explants infection experiments in vitro.The author highlights the establishment,pathogenesis,host responses and application of the different APEC experimental infection models.     

Retrospective Identification of Bacterial Isolates From Emergency Laparotomy Surgical Site Infections in Horses

Surgical site infection (SSI) with multiresistant bacteria is an important cause of postoperative morbidity after laparotomy in horses. The objective of this study was to identify bacteria isolates and their antibiotic resistance patterns associated with the development of wound infection in horses after laparotomy. This is a retrospective case series. Medical records of horses that underwent ventral midline exploratory laparotomy in a four-year period at one equine hospital were reviewed. Results of microbiologic culture and susceptibility testing are described. The study group consisted of 183 (100%) horses that recovered from anesthesia after laparotomy. The prevalence of infection was 19% (24/124) after first surgery and 83% (19/23) after relaparotomy. The most common microbial isolates were bacteria of the family Enterobacteriaceae followed by Staphylococcus ssp., Enterococcus ssp., Streptococcus ssp., and Bacteroides ssp. Bacteria from the family Enterobacteriaceae showed the lowest resistance to amphenicols, cephalosporins, and quinolones groups of antibiotics. Coagulase-positive Staphylococci were sensitive to amphenicols and only 33% were resistant to trimethoprim/sulfamethoxazole. The most commonly used perioperative and postoperative antibiotics were gentamicin and amoxicillin. Limitations include poor control over exposure factors, covariates, and potential confounders during the surgery, recovery time, or period of hospitalization; relying on others for accurate outcome assessment and recordkeeping; lack of follow-up information once animals were discharged from the hospital. Despite 5 days of antibiotic prophylaxis, the rate of incisional infection is still high. The most common isolates from SSI belong to the family Enterobacteriaceae and the genus Staphylococcus, which showed high resistance to the antibiotics used before the gastrointestinal surgery.