沙拉沙星对实验性感染猪链球菌病及大肠杆菌病的药效学

为兽医临床合理应用沙拉星（Ｓarafloxacin）提供理论依据,就其对实验性感染猪链球菌 病及大肠杆菌病的药效学进行了研究。以试管２倍稀释法测得沙拉沙星对兰氏Ｃ群类马链球菌（Ｃ５５１２０）和猪大肠杆菌（Ｏ５５）的最小抑菌浓度（ＭＩＣ）分别是０．８mg/Ｌ及０．０５mg/Ｌ。肌注给药对猪链球菌病和大肠杆菌病的试验性治疗结果不明,低、中 高剂量沙拉沙星组２．５、５、１０mg/kg）及环丙沙星组（５mg/kg）用药５d（每隔１２     

新城疫活疫苗对控制鸡大肠杆菌病的效果观察

为了研究鸡新城疫活疫苗紧急免疫控制鸡大肠杆菌病的效果,通过大肠杆菌人工感染30日龄蛋鸡,待出现病症后,紧急免疫新城疫La-sota弱毒苗(Ⅳ系)4羽份.免疫后5～17 d,通过血凝抑制试验测定血清新城疫抗体水平,试验组新城疫抗体水平逐步提高,对照组抗体略有下降,免疫后17 d两组抗体水平差异显著(P＜0.05);对照组...     

中药克痢散对鸡大肠杆菌病防治效果研究

根据中兽医学理论和中医药在现代医学上的应用成果，以石膏、滑石、白头翁、苍术等组方制成克痢散，经过药敏对比试验、对比治疗试验及区域性治疗试验，其对鸡大肠杆菌病最高治愈率97．6％，平均为97.3％。     

复方白毛藤注射剂对仔猪大肠杆菌病的疗效研究

本试验研究了复方白毛藤注射液对大肠杆菌的体外抑菌作用和对猪大肠杆菌病的治疗效果。结果表明,该制剂对大肠杆菌的抑菌效果明显,其抑菌圈直径为(16.7±1.12)mm。该制剂对仔猪黄白痢的治疗效果显著,总治愈率为94.3％,明显高于药物对照组(P<0.01)。     

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。     

Preparation and Evaluation of Mixed Probiotics for Chicken Against Escherichia coli Infection

The purpose of this study was to explore the effects of probiotics on chickens' resistance to Escherichia coli infections,and to provide a basis for the development of microecological agents.Based on the Oxford Cup test and the bacterial adhesion inhibition test,three kinds of probiotics and their equal proportion mixed bacterial liquid with good effect of inhibiting Escherichia coli in vitro were obtained initially:Lactobacillus plantarum ZN-3,Lactobacillus rhamnosus QC,Clostridium butyricum HYCB and mixed bacteria preparation X.The 7-day-old SPF chicks were continuously orally fed with probiotics for 30 days and infected with Escherichia coli XT-13 once a day from the 26th to 30th day,and the survival rate and weight change were recorded.Through the same oral and infection protocols,the chicks were necropsied after infection with XT-13,and the results of necropsy and pathology were analyzed,and the amount of bacteria in the liver and intestines was detected by immunohistochemistry.In addition,in order to analyze the effect of oral administration of mixed probiotic preparations on cytokines in chickens infected with Escherichia coli,non-lethal doses of XT-13 were selected to infect chickens,and the levels of interleukin-10 (IL-10),interleukin-17 (IL-17) in serum and avian defensin-β1 (AvBD1) in the liver were measured on the 4th,8th and 14th days after infection.At the same time,the bactericidal ability of the serum was tested on the 14th day after infection.Finally,the broad-spectrum protection ability of probiotics to O78 serotype Escherichia coli AV006 infected chickens was evaluated.The results showed that the antibacterial effect of the supernatant of each probiotic fermentation broth was obvious,and the mixing of probiotics could reduce the adhesion rate of XT-13 to DF-1 cells (P<0.05).The weight gain effect of mixed probiotics was better than that of single probiotics,which had a good protective effect on chickens infected with XT-13.The survival rate was 87.50%.The mixed probiotics significantly reduced the load of XT-13 in liver and large intestine,alleviated the pathological damage,and regulated the levels of IL-10 and IL-17 in serum and the levels of AvBD1 in the liver,while improving the bactericidal ability of the serum.In addition,the broad-spectrum protection test showed that the mixed probiotics reduced the mortality of chickens infected with O78 serotype Escherichia coli.Therefore,the mixed preparation of Lactobacillus plantarum ZN-3,Lactobacillus rhamnosus QC and Clostridium butyricum HYCB could promote chick weight gain,reduce bacterial load,reduce tissue lesions,regulate the host's immune response,and had a good prevention effect on avian colibacillosis,which had a great potential to develop into a probiotic preparation against avian colibacillosis.     

A Single-chain Fragment Variable Recombinant Antibody against F5 Fimbria of Enterotoxigenic <Emphasis Type="Italic">Escherichia coli</Emphasis> Inhibits Agglutination of Horse Red Blood Cells Induced by F5 Protein

Bovine colibacillosis caused by enterotoxigenic Escherichia coli (ETEC) is a worldwide problem. Adhesion of ETEC to intestinal cell receptors mediated by the surface protein F5 fimbriae is the initial step in the establishment of colibacillosis. Prevention of ETEC F5⁺ adhesion to enterocytes protects newborn calves against collibacillosis. On the enterocytes, the F5 fimbriae bind to a ganglioside that is also found on horse red blood cells. Thus, the presence of F5 fimbriae induces haemagglutination, which is useful as an indicator in a functional assay system. In this study, recombinant anti-F5 scFv antibody fragment produced in E. coli HB2151 reacted with F5 fimbriae in ELISA and Western immunoblot, and prevented haemagglutination induced by the binding of the F5 fimbriae to its natural host receptors on horse red blood cells. Given the ease with which recombinant antibodies can be mass-produced, the presently described scFv may hold promise as a prophylactic agent for colibacillosis.     

头孢噻呋钠对1日龄雏鸡实验性感染鸡大肠杆菌病的药效试验

通过预先颈部皮下注射头孢噻呋钠,评价其对1日龄雏鸡试验性诱导大肠杆菌病的预防效果。以微量法测得头孢噻呋钠和恩诺沙星对鸡大肠杆菌的MIC分别为0.1mg/L和1.6mg/L。试验结果表明,0.2、0.1、0.05mg/只的头孢噻呋钠各用药组对人工诱导鸡大肠杆菌病的保护率分别为100%、90%和80%,与0.125mg/只的恩诺沙星对照组(63.33%)及感染对照组(46.67%)相比,头孢噻呋钠各剂量组均能显著降低1日龄雏鸡人工诱发大肠杆菌病的死亡率(P<0.01),具有很好的预防效果;试验结束后细菌学检测结果表明,头孢噻呋钠各剂量组和药物对照组鸡的大肠杆菌检出率分别为13.33%、23.33%、30.0%、46.67%,与感染对照组(90%)相比均显著减少(P<0.01)。     

鸡大肠杆菌病的诊治报告

2005年3月1日,宁夏回族自治区中卫市某镇养鸡大户饲养的1500只（150d）蛋鸡陆续发生腹泻、死亡．经过临床症状、病理剖检、组织病理学、细菌培养、生化试验、药敏试验等诊断方法,确诊为鸡的大肠杆菌病,并为地方流行病．在确诊的基础上,采取了药物治疗、环境消毒、加强管理、淘汰病鸡等综合防治措施,使病情得到了控制．截止3月15日,再没有出现死亡现象,产蛋率由75％上升至90％．