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1.
新疆地区规模化奶牛场牛支原体流行病学调查 总被引：2，自引：0，他引：2
为了调查新疆地区规模化奶牛场牛支原体的感染情况,采用牛支原体间接ELISA和特异性PCR检测牛血清中的牛支原体抗体及病料中牛支原体核酸,共检测9个地区15个规模化奶牛场437份血清,肺脏、关节液及鼻腔黏液44份。结果显示,血清抗体阳性率为76.43%（334/437）,其中脐带血抗体阳性率为40.00%（4/10）;病料阳性率为40.91%（18/44）。检测结果表明,新疆地区大部分奶牛场存在牛支原体感染,部分奶牛场发生牛支原体肺炎及关节炎病例,并存在垂直传播的风险。牛支原体感染可能成为危害新疆规模化奶牛场犊牛健康的主要疫病之一。 相似文献
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银川地区某奶牛场牛支原体病的诊断 总被引：1，自引：0，他引：1
为确诊银川市某奶牛场成年奶牛病因,本研究对两头表现明显临床症状的犊牛进行解剖,无菌采集肺脏、肺积液、关节液及患临床型乳房炎的奶牛乳样1份进行病原分离,分离到2株巴士杆菌、2株链球菌、1株大肠杆菌和3株支原体,通过革兰氏染色、菌落形态观察、特异性PCR鉴定和16S r RNA序列比对,结果显示引起此次流行的主要病原为牛支原体。采用比利时进口牛支原体ELISA诊断试剂盒对银川地区12个规模化奶牛场的230份奶牛血清进行牛支原体血清学调查,结果显示牛群平均阳性率26.52%,牛场阳性率高达100%,表明牛支原体病在银川地区呈高感染率。 相似文献
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《中国奶牛》2017,(3)
由牛支原体引起的奶牛支原体肺炎和乳房炎所导致的经济损失非常巨大,而目前我国尚无较详细的奶牛牛支原体病流行病学资料。2008~2016年,本课题组采用牛支原体间接ELISA、直接培养法和特异性PCR检测法对国内12个地区30个规模化奶牛场进行了牛支原体感染情况调查及分析,共对843份血清和60份肺脏、关节液及鼻腔黏液、1 090份乳样中的牛支原体抗体和牛支原体及其核酸进行了检测。结果显示,血清抗体阳性率为52.31%(441/843);病料阳性率为55%(33/60);乳样阳性率为34.22%(373/1090);从样本中共分离保存了55株支原体菌种。检测结果表明,国内大部分奶牛场存在牛支原体感染,部分奶牛场发生牛支原体肺炎、乳房炎及关节炎临床病例,并存在垂直传播的风险。牛支原体感染可能成为危害国内规模化奶牛场奶牛健康的主要疫病之一。 相似文献
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本研究旨在调查新疆喀什某规模化奶牛场的犊牛死亡原因,并确定病原体.无菌采集3份因肺炎死亡的犊牛肺脏病料样品.采用牛支原体专用液体培养基和1.0%牛支原体琼脂固体筛选培养基从3份病死犊牛肺脏病料中分离得到2株牛支原体(Mycoplasma bovis,M.bovis),分别命名为M.bovis-NJ-1和M.bovis-NJ-2.通过菌落形态学观察、特异性PCR和oppF测序比对对分离株进行鉴定.结果显示,2个分离株在固体培养基上的菌落呈现典型的"煎蛋状",且Dienes染色特点符合牛支原体菌落着色特征,中心呈深蓝色;PCR能扩增出牛支原体特异的448 bp目的片段;2个分离株的oppF基因序列与牛支原体国际标准株PG45的同源性分别为96.7%和95.3%.结果表明,引起犊牛发病死亡的病原是牛支原体,本研究为犊牛支原体肺炎的快速诊断和防制提供依据. 相似文献
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2019年6月,大庆市某奶牛场发生犊牛肺炎,表现为呼吸困难,短促咳嗽,病程2周左右,发病率约50%～80%,病死率约20%～30%。为确定该奶牛场犊牛因肺炎而致死的病因,本试验进行了临床诊断及实验室诊断,对病死牛肺脏进行细菌分离培养,经检测怀疑为支原体感染,又进一步利用PCR方法检测,检测结果确定为牛支原体感染,并对该牛场支原体进行药敏试验,药敏结果对卡那霉素、四环素、恩诺沙星、泰妙菌素、环丙沙星和土霉素高度敏感。可见牛支原体感染是该牛场发病的重要原因,筛选出的敏感药物可用于治疗发病牛,该结果为奶牛场犊牛肺炎的防控提供了参考依据。 相似文献
7.
国内首次从患肺炎的犊牛肺脏中分离到牛支原体 总被引：23，自引：2，他引：21
牛支原体(Mycoplasma boris)是引起犊牛肺炎、关节炎和成牛乳房炎的主要病原之一.本研究利用选择性培养基从2份患肺炎的犊牛肺脏病料中得到2株支原体,分别命名为Hubei-1和Hubei-2,并在固体培养基进行了3次克隆纯化.通过生化实验、特异性PCR鉴定和序列比较证明为牛支原体.其16S rRNA 核酸序列与牛支原体国际标准株PG45同源性为99.3%.以该培养物作为包被抗原的ELISA 检测方法对13份发病犊牛血清进行了检测,其中11份血清抗体OD值为阴性血清对照值的2倍以上.该结果首次证实,国内部分地区存在牛支原体的流行. 相似文献
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2009年2月～6月我国某奶牛场发生严重的犊牛多发性关节炎,发病犊牛的症状与最早发生于澳大利亚的犊牛Leachii支原体关节炎非常相似。为确定病原,我们无菌采集2份具有典型症状犊牛的关节液样品进行实验室诊断,2份样品中均检测和分离出支原体。将2个分离菌株的16S rRNA基因和LppA基因与参考支原体菌株进行核苷酸序列比对,发现这2株支原体的16S rRNA基因和LppA基因均与Leachii支原体具有最高的核苷酸序列同源性,分别为99.9%和99.6%。结果显示,本研究分离的2株支原体为Leachii支原体,分别命名为GN407和GN408。综合分析发病犊牛的临床病理学观察和关节液样品的实验室诊断结果,我们确定Leachii支原体为该奶牛场犊牛多发性关节炎的病因。 相似文献
9.
为确定新疆塔城地区某奶牛场部分断奶犊牛出现咳嗽、流脓性鼻涕、腹泻等症状的发病病因,本试验通过对采集到的发病犊牛鼻拭子样品进行分离培养、形态学观察、生化试验、16S rRNA基因和oppD/F基因PCR扩增与测序、药敏试验等。分离培养显示3株分离株在改良Thiaucourt’s琼脂培养基平板上生长出典型的“煎蛋样”菌落,狄氏染色菌落中心呈深蓝色。生化试验中分离株不发酵葡萄糖与甘露醇,不水解精氨酸,不分解尿素,明胶液化试验为阴性。PCR扩增分离株16S rRNA基因测序结果显示,分离株与GenBank数据库中牛支原体16S rRNA基因序列的相似性在98.73%以上;牛支原体特异性基因oppD/F阳性且相似性达99.74%以上。通过药敏试验从9种药物里选择出替加环素、红霉素2种最为敏感的药物。研究结果表明,造成此次犊牛肺炎的病原菌为牛支原体,为临床防治牛支原体病提供了参考。 相似文献
10.
为了解新疆地区部分规模奶牛场牛病毒性腹泻病（BVD）的流行情况,优化防控措施,以达到建设防控净化场的目的,自2020年11月到2021年7月累计采集新疆5 个地区16 个奶牛场共计26 997 份血清、3 843 份犊牛耳组织进行全群普检。通过使用IDEXX公司牛病毒性腹泻病毒（BVDV）抗原检测试剂盒检测及RT-PCR复检结合测序等方法,淘汰阳性牛,同源性分析流行毒株情况。BVDV血清抗原检测结果为：沙湾某奶牛场BVD阳性率为1.63%（38/2 326）;乌鲁木齐某奶牛场BVD阳性率为0.35%（4/1 132）;其余奶牛场均为阴性。犊牛耳组织抗原检测结果为：乌鲁木齐某牛场BVDV阳性率为1.17%（4/342）;其余奶牛场均为阴性。研究结果揭示,奶牛场通过淘汰BVDV阳性牛,调整免疫程序、制定消毒程序等方法,可有效净化BVD。 相似文献
11.
In studies to determine whether there were antigenic differences between strains (isolates) of Moraxella bovis, the sera from vaccinated calves were tested with isolates of M bovis while the calves were experiencing epizootics of infectious bovine keratoconjunctivitis (IBK). Before the epizootics of IBK, the calves were intramuscularly vaccinated with a formalin-killed autogenous M bovis bacterin. During the epizootics, the eyes were examined by cultural technique, and isolates which were obtained were categorized by catalase activity, source (diseased or nondiseased eyes), and reactivity with the various sera. The serum reactivity of the isolates was compared with that of the vaccinal strain. The vaccinal strain and 8 of the 1 5 selected isolates obtained during the 1974 epizootic were catalase negative. Seven of the 15 isolates from the 1974 epizootic and all of the selected isolates from the 1975 epizootic were catalase positive. A significantly higher (P less than 0.01) percentage of calf sera were serologically reactive with the vaccinal strain and other catalase-negative isolates (45.0%) than with catalase-positive isolates (34.8%). The results, although not definitive, suggest that there may be antigenic differences among strains of M bovis. These differences should be considered when cattle are vaccinated against IBK under natural conditions of exposure. 相似文献
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An in vitro assay was developed using calf corneal cells to assess the importance of fimbriae in the colonisation of the bovine ocular surface by Moraxella bovis, and the role of fimbrial antibodies in the bovine immune response and resistance to infectious bovine keratoconjunctivitis (IBK). Fimbriae promoted adherence of M. bovis to calf corneal cells in culture; 15 fimbriate isolates, representative of 6 fimbrial serogroups of M. bovis, adhered to the cells whereas 4 non-fimbriate isolates failed to do so. Fimbrial antibodies in hyperimmune rabbit serum inhibited attachment of all fimbriate strains of the homologous fimbrial serogroup but not those of 5 heterologous serogroups. The relevance of these results to the use of a polyvalent fimbrial vaccine in the control of IBK is discussed. 相似文献
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A Feenstra E Bisgaard Madsen N F Friis A Meyling P Ahrens 《Zentralblatt für Veterin?rmedizin. Reihe B. Journal of veterinary medicine. Series B》1991,38(3):195-202
After an outbreak of mastitis in cattle caused by Mycoplasma bovis a study was made in 5 herds with recent cases (principal herds) and in 4 control herds. In the principal herds, M. bovis was isolated from milk samples, nasal swabs, and from one vaginal swab. M. bovis was also isolated from nasal swabs of calves in 2 of the 4 control herds, whereas all milk samples and vaginal swabs from the control herds were negative. Evaluation of serum antibody titres to M. bovis among non-mastitic animals of 3 principal herds and 1 control herd showed no difference in distribution of the titre values, which generally were low. However, cows excreting M. bovis in the milk had high antibody titres. The way of introduction to the herds and the spread of the infection within the herds could not be established by the study, which was supplemented by a DNA restriction fragment analysis of a number of M. bovis isolates. 相似文献
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E Bender J Fritzsche M B?r W Nordheim 《Archiv fuer experimentelle veterinaermedizin》1989,43(5):783-788
Reported in this paper is the use of 60Co gamma radiation to inactivate mycoplasmas in calf serum, newborn calf serum, and fetal calf serum. A dose of 3 kGy, independent of dose rate, was found to be sufficient for inactivation in the above sera of several mycoplasmas, including Acholeplasma laidlawii, Mycoplasma (M.) orale, M. arginini, M. hyorhinis, and M. bovis. The critical dose proved to be at 2 kGy. No difference was found to exist between the above species in susceptibility to irradiation in diluted sera (50%) and 10% in Eagle MEM). Sensibility of wild mycoplasma strains was found to be identical with that of laboratory strains. Hence, 60Co gamma irradiation of sera appears to be a safe method by which to make sera mycoplasma-free. Bacillus subtilis in calf serum was inactivated by doses above 18 kGy, with the critical dose being 15 kGy. 相似文献
15.
Hirose K Kobayashi H Ito N Kawasaki Y Zako M Kotani K Ogawa H Sato H 《Journal of veterinary medicine. B, Infectious diseases and veterinary public health》2003,50(7):347-351
Nasal swabs of 293 calves were examined for Mycoplasma. The samples were collected from calves affected with respiratory diseases on 71 farms in various parts of Japan between 1996 and 1997. Mycoplasma bovirhinis was isolated from 47 of 293 calves (16.0%). Mycoplasma alkalescens, M. bovis, M. arginini, M. bovigenitalium and Acholeplasma spp. were isolated from 19 (6.5%), seven (2.4%), four (1.4%), four (1.4%) and 18 (6.1%) calves, respectively. Pasteurella multocida and P. haemolytica were isolated from 60% of Mycoplasma-positive calves. However, other bacteria were not isolated from calves. To evaluate the antimicrobial susceptibility of their isolates, 68 M. bovirhinis, 21 M. alkalescens and 10 M. bovis strains were examined for 12 antimicrobial agents. All isolates showed higher susceptibility to tiamulin than to the other drugs used in the study. However, erythromycin had no effect on any of the Mycoplasma strains studied. The field isolates were less susceptible than the type strains to some drugs, such as spiramycin, oxytetracycline and tylosin. 相似文献
16.
Stability, antigenicity, and aggregation of Moraxella bovis cytolysin after purification and storage
OBJECTIVES: To compare stability, antigenicity, and aggregation characteristics of Moraxella bovis cytolysins among isolates from geographically diverse areas. STUDY POPULATION: 8 isolates of M. bovis. PROCEDURE: Filter-sterilized broth culture supernatants of M. bovis were concentrated, diafiltered, and chromatographed. The endotoxin and cytolysin activities in samples were measured. Chromatographed cytolysins of M. bovis were examined by immunoblotting. Hemolytic and leukotoxic activities were measured from samples collected at each step of purification and before and after storage. Hemolysis was measured directly by use of washed bovine erythrocyte targets. Leukotoxicity was measured by use of a 51Cr release assay. RESULTS: Cytolysin was retained by a filter with 100-kd nominal molecular weight limit. Hemolytic activity, leukotoxic activity, and endotoxin were eluted together in void volume of a gel-filtration column (molecular mass exclusion limit = 4 X 10(7) d). Gel-column chromatographed diafiltered retentate had the greatest specific cytolytic activity and the highest endotoxin-to-protein ratio. Frozen diafiltered retentate(-80 degrees C, 4 months) was cytolytic after thawing. Immunoblots of gel-column chromatographed cytolysin contained 4 proteins with molecular masses between 90 and 68 kd. Fractions with high lytic activities also had additional protein bands with molecular masses of 98 and 63 kd. Immunoblots of gel-column chromatographed diafiltered retentate revealed proteins with molecular masses between 90 and 68 kd. CONCLUSIONS AND CLINICAL RELEVANCE: Diafiltered M. bovis cytolysin is aggregated with endotoxin. Antigenicity and cytolytic activities in diafiltered retentate are conserved among M. bovis isolates. Diafiltration could be useful for bulk semipurification of M. bovis cytolysin. Cytolysin-enriched vaccines of M. bovis could be contaminated by endotoxin. 相似文献
17.
Arcangioli MA Aslan H Tardy F Poumarat F Le Grand D 《Veterinary journal (London, England : 1997)》2012,192(1):96-100
Mycoplasma bovis is a major cause of respiratory outbreaks in cattle feedlots. In this study pulsed-field gel electrophoresis (PFGE) was used to trace field strains and provide information on M. bovis patterns of spread in calf feedlots. The suitability of KpnI, MluI and SmaI restriction enzymes was assessed on different sets of strains. The discriminative power of the first two enzymes was first assessed using 28 epidemiologically unrelated strains; stability was 100% on multiple isolates from in vivo experimental infection. Thirty-nine field isolates from six feedlots were then evaluated. In contrast to the unique fingerprints displayed by the unrelated strains, the isolates from the feedlots showed identical patterns at the time of the outbreak of respiratory disease and 4 weeks later. The PFGE typing results suggest that M. bovis strains follow a clonal epidemic spread pattern at the herd level and that the same strain persists in calves of the herd after the clinical signs have disappeared. 相似文献
18.
Pillai SD Widmer KW Ivey LJ Coker KC Newman E Lingsweiler S Baca D Kelley M Davis DS Silvy NJ Adams LG 《Preventive veterinary medicine》2000,43(1):53-62
The State of Texas had the most (cumulative) tuberculous cattle herds of any state in the United States during the decade ending in 1997. Of the cumulative 18 infected herds in Texas, 12 herds were concentrated in El Paso County (designated the 'El Paso milkshed'). To identify whether non-bovine reservoirs were a source of Mycobacterium bovis infection of cattle in this region, an investigation was conducted on the premises of 14 dairy herds (12 tuberculous and 2 non-affected herds) between May 1995 and June 1997. None of the 670 mammalian, avian and environmental (soil, water and air) samples collected and cultured from the premises of these herds was positive for the presence of M. bovis. None of the 119 human urine samples obtained from employees of these dairies was culture positive for M. bovis. Of 124 dairy-farm workers with tuberculin skin-test results, 48 showed positive test results. There was, however, no difference in percentages of positive skin-test results between farms without, and farms having, bovine tuberculosis within the last two years or longer. The percentage of positive reactions did not increase with length of time employed at a dairy with a history of confirmed tuberculosis. These findings suggest that non-bovine reservoirs appear not to be a factor responsible for tuberculosis of cattle in the El Paso milkshed. 相似文献
19.
为调查新疆规模化奶牛场病牛死亡原因并确定病原,本研究无菌采集7份肺炎病死牛病变肺组织样,通过牛支原体液体培养基和固体培养基分离到1株支原体,采用形态学观察和生化试验鉴定该分离株,采用支原体特异性引物和牛支原体16S rRNA通用引物扩增基因序列并测序,使用DNAStar软件将分离菌株测序结果与GenBank中的标准株序列进行同源性比对,采用Mega 6.0软件中的邻接法(Neighbor-Joining,NJ)依据16S rRNA序列构建分离株系统进化树。结果显示,分离株菌落呈典型的"煎蛋样",菌落中心凹陷深入培养基,周边菲薄而透明,经Dienes染液染色后,菌落中心呈深蓝色。该分离株不分解葡萄糖、尿素、不水解精氨酸,血细胞吸附试验和溶血试验均呈阴性,氯化三苯基四氮唑还原反应呈阳性,产生膜和斑。PCR反应扩增出大小为1 911 bp的牛支原体特异性目的片段;分离株16S rRNA基因序列与牛支原体标准株PG45的序列同源性为99.8%,与牛支原体地方株(Mb NM2012、Mb HB0801、Mb Hubei-1、Mb Ningxia-1、Mb CQ-W70和Mb 08M)的同源性为99.3%～99.7%。系统进化树显示,分离株16S rRNA基因与Mb Ningxia-1株和Mb 08M株亲缘关系较近,处于同一分支。本研究结果证实了引起病牛死亡的病原为牛支原体,为新疆牛支原体病的防治提供了科学依据。 相似文献