绵羊刚果嗜皮菌的分离鉴定及某些生物学特性研究

从疑似嗜皮菌感染绵羊的皮肤疙瘩病料中分离到1株细菌,通过对其形态、培养特性、生长特征、生理生化特性、16S rRNA基因序列测定与同源性分析等研究,证明分离株为刚果嗜皮菌。人工感染羔羊表现出与自然发病绵羊相同的症状并死亡,从人工感染死亡绵羊皮肤中再次获得同种细菌。药敏试验结果表明:该菌对林可霉素、卡那霉素、氧氟沙星、复方磺胺、土霉素、氟苯尼考高度敏感。     

绵羊嗜皮菌病PCR诊断方法的建立

为建立动物嗜皮菌病的PCR检测方法,根据GenBank发表的刚果嗜皮菌属的部分16s-rRNA基因序列,设计了1对特异性引物.经PCR扩增,从发病绵羊皮肤病料提取的基因组DNA得到了大小约500 bp的DNA片段.将PCR产物克隆并测序表明,与GenBank发表的刚果嗜皮菌基因序列的同源性为90.632%.而猪胸膜肺麦放线杆菌、大肠杆菌、葡萄球菌、肠球菌扩增结果为阴性;PCR的敏感性试验显示,这时引物能够检测到1 ng的DNA.表明此PCR方法特异性好,敏感性高,可用于嗜皮菌病的快速诊断.     

澳牛嗜皮菌病1例

嗜皮菌病也叫链丝菌病,是一种由刚果嗜皮菌引起的牛和其他大动物常见的皮肤感染。炎热潮湿的环境易引起刚果嗜皮菌的接触感染,皮肤的机械性伤害以及外寄生虫损伤皮肤也会造成刚果嗜皮菌的感染和传播。2005年11月底,新疆兵团农七师123团澳牛场要求对该场1份病料进行化验,病料为浓稠的黄绿色脓汁,来自患病牛的局部病灶。患牛背部有1个拳头大肿块,右侧后乳房上有1个乒乓球大肿块,无其他异常。1临床症状病牛患部有轻微隆起,皮肤表面附着毛发并有痂皮,局部穿刺有浓稠的黄绿色脓汁。移走结痂的毛发丛,可露出粉红色真皮层。2诊断染色镜检:无菌抽取…     

不同消毒防腐剂预防绵羊刚果嗜皮菌病临床效果观察

<正>绵羊刚果嗜皮菌病是近年来新传入我国的外来人畜共患病种,世界动物卫生组织(OIE)将其定为B类传染病。该病病原在1915年首次在刚果发病牛身上分离到,目前已经在世界许多国家发生并且有蔓延的趋势。1969年,我国首次从牦牛身体上分离到绵羊刚果嗜皮菌;2002年6月份,绵羊刚果嗜皮菌病在新疆塔敏垦区161团发生并首次在国内报道。由于对该病防治缺乏基本的认识与经验,又无有效疫苗预     

奶水牛牛分枝杆菌的分离与鉴定

从患疑似结核病的广西奶水牛群中进行牛分枝杆菌的分离和鉴定。共收集了238份临床样品(鼻黏液及牛奶),病料经1.25 mol/mL NaOH溶液预处理后,接种罗氏培养基进行细菌分离。分离菌经进一步纯化后进行抗酸性染色并镜检,镜检后判为阳性的细菌再接种到鉴别培养基上进行鉴别培养,同时,应用PCR方法对镜检为阳性的细菌进行进一步的鉴别检验。结果收集的所有临床样品,经37℃培养后共获得细菌12株。这12株菌经抗酸性染色后镜检都为分枝杆菌阳性,进一步经鉴别培养基鉴定12株菌中有2株为牛分枝杆菌,其余均为非典型分枝杆菌。2株牛分枝杆菌经PCR方法鉴定得以确诊。     

刚果嗜皮菌的研究进展

刚果嗜皮菌（Dermatophilus congolensis）于1915年首次在刚果的发病牛分离到.嗜皮菌病在非洲很普遍,现已在世界上许多国家发生并有扩大蔓延的趋势.我国于1969年从牦牛身上发现并分离到该菌,1984年兰州兽医研究所检查了19个省区的黄牛、奶牛和水牛,均有不同程度的抗体存在.现将该菌的研究现状简述如下.     

绵羊刚果嗜皮菌病研究进展

<正>绵羊刚果嗜皮菌病是由刚果嗜皮菌(Dermatophilus congolensis)引起各种动物及人的一种皮肤传染病,曾称绵羊真菌性皮炎、疙瘩羊毛病、羊毒样腐蹄病、皮肤雨伤病,以头部、腹部和四肢皮肤形成紧密粘着的毛结和红棕色痂块性皮疹为特征。1病原学嗜皮菌属于嗜皮菌科(Dermatophilaceae)嗜皮菌属(Dermatophilus)的成员,菌体结构因培养基类型及培养时间不同而不同,有菌丝期和孢子期两个     

疑似草鱼嗜水气单胞菌的分离鉴定及药敏试验

试验对疑似嗜水气单胞菌草鱼的肝脏、脾脏、肾脏组织进行嗜水气单胞菌的分离鉴定。通过普通营养琼脂、胰蛋白大豆琼脂及生化试剂等的分离培养与生化鉴定后,获得3株细菌;16S rRNA通用引物检测3株细菌的基因序列比对确定菌株后,对确定的草鱼嗜水气单胞菌进行回归试验确认其致病性,然后采用临床上常用的阿奇霉素、阿米卡星、链霉素等10种抗生素进行药敏试验。结果表明,经过分离培养、生化鉴定及16S rRNA通用引物鉴定后确定3种菌株分别为嗜水气单胞菌、嗜麦芽窄食单胞菌和腐败斯瓦尼菌,确定的嗜水气单胞菌回归试验证明其具有致病性;药敏试验显示阿奇霉素对腐败斯瓦尼菌和嗜麦芽窄食单胞菌敏感,其抑菌直径分别为105、95 mm,阿米卡星对嗜麦芽窄食单胞菌、嗜水气单胞菌和腐败斯瓦尼菌这3种菌都较敏感,抑菌直径分别为105、95和93 mm。结果表明,疑似为嗜水气单胞菌病的草鱼有3种细菌感染,其中鉴定的嗜水气单胞菌是致病菌,常用抗生素阿米卡星对3种菌都有抑制作用,而仅对腐败斯瓦尼菌和嗜麦芽窄食单胞菌敏感的是阿奇霉素。     

牛、羊嗜皮菌病的剖检变化与实验室检验

1病原及其传播 牛、羊嗜皮菌是由刚果嗜皮菌引起牛、羊皮肤传染病，以形成局限陛痂块和脱屑性皮疹为特征。刚果嗜皮菌为革兰氏阳性、非抗酸的需氧或兼性厌氧菌，     

青贮料中肠球菌的分离与筛选

本试验从青贮料中分离肠球菌并对分离菌株进行初步鉴定与筛选,通过正交试验设计研究不同温度、初始pH和瘤胃液含量对3株分离菌生长的影响,筛选出适合作为奶牛饲用微生物的菌株。结果表明,3株分离菌的最佳培养条件相同为：培养基含葡萄糖2%、蛋白胨1%、瘤胃液20%、初始pH为5.8,接种量为3%,装液量为40 ml, 36℃培养24 h。 在该条件下,3株分离菌的生物量分别为1.9907、1.2963和1.2752。选择生物量最高的1号菌送中科院微生物所鉴定,结果为屎肠球菌。     

Relationship between chronic ovine dermatophilosis and levels of T6 lymphocyte antigen staining in peripheral blood mononuclear cells.

Quantification of a T6-lymphocyte antigen in peripheral blood mononuclear cells of sheep was used to select 15 from 48 one year old Merino ewes not previously exposed to Dermatophilus congolensis infection. These sheep were compared in response to challenge with D. congolensis zoospores and levels of T-6 lymphocyte antigen in peripheral blood mononuclear cells with 15 Merino ewes of similar age and strain from a different site that had been treated and recovered from chronic dermatophilosis. The T-6 lymphocyte antigen levels were significantly lower in the chronic dermatophilosis sheep and they developed significantly more severe lesions than the selected, previously unexposed sheep despite the former sheep having high serum antibody levels to D. congolensis. Measurement of the fleece characteristics, wax and suint concentration showed no differences between the groups that might have explained the considerable differences in their susceptibility to dermatophilosis.     

Inhibition of Dermatophilus congolensis by substances produced by bacteria found on the skin

Bacteria, isolated from the skins of clinically normal sheep, were tested for inhibitory activity against Dermatophilus congolensis grown in vitro. Out of 85 bacterial isolates, 19, mainly Bacillus spp., showed zones of inhibition when grown together with D. congolensis. The inhibitory activity was shown to be due to the metabolites released by the bacteria.     

Serum and skin surface antibody responses in merino sheep given three successive inoculations with Dermatophilus congolensis

Three antigens prepared from different phases of the life cycle of Dermatophilus congolensis were used in an enzyme-linked immunosorbent assay to measure serum and skin surface antibody responses in sheep after a first, second and third inoculation with D. congolensis. After the first inoculation, a strong antibody response to the flagella, filament and soluble antigens was detected after 7-21 days in the sera from sheep that were regularly biopsied; the antibody response at the skin surface was detected 28-42 days after inoculation, when the lesions were resolving. Strong anamnestic responses were detected in the serum of sheep that were biopsied and some of the nonbiopsied sheep after the second and third inoculations, but the skin surface antibody response at these times was variable.     

The anti-bacterial activity of acaricides in relation to streptothricosis

The anti-bacterial activity of 13 commercially available acaricides, in use in the Caribbean, was tested against Dermatophilus congolensis, an actinomycete involved in streptothricosis of cattle, sheep and goats in the tropics. Acaricides used included organochloride, organophosphorus, carbamate, pyrethroid and amidine compounds. Each acaricide was tested at a typical working dilution used by the farmers, at 25 degrees C and 37 degrees C, in the presence or absence of 15 percent newborn calf serum as a fouling agent. Fouling of acaricides was found to have a marked inhibitory effect on its anti-bacterial activity. Vapona and Cattle Washing Detergent were found to be more active against Dermatophilus congolensis than the other acaricides tested.     

Cellular responses in the skin of merino sheep to repeated inoculation with Dermatophilus congolensis

The cellular response in the skin of Merino sheep was examined after three successive inoculations with Dermatophilus congolensis. There was a massive neutrophil influx into the infected epidermis and underlying dermis at 4-10 days after the first inoculation. A lymphocyte-macrophage response occurred at 10-12 days, followed by a plasma cell response at 14-38 days. Resolution of skin lesions after the first inoculation corresponded to the time when the plasma cell response in the skin was most intense. A second inoculation with D. congolensis, 70 days after the first, failed to produce skin lesions typical of dermatophilosis. Typical lesions of dermatophilosis did develop after a third inoculation of the same sheep 140 days after the first inoculation, but the lesions resolved in most sheep within 13 days. Dermatophilosis did not develop in some of these sheep at sites inoculated with 100-1000-fold lower infective doses of D. congolensis, whereas control sheep did develop lesions.     

Strain variation in Dermatophilus congolensis demonstrated by cross-protection studies

Cross-protection studies were conducted with vaccines prepared from two isolates of Dermatophilus congolensis (designated strain 1 and strain 2). The vaccines were prepared as either heat-inactivated, washed, formalized filamentous phase bacterium, mixed with alum as an adjuvant, and inoculated intramuscularly (type A vaccine) or sedimented live filaments inoculated intradermally (type B vaccine). The vaccinated sheep were challenged with D. congolensis zoospores of one or other strain. Challenge sites were observed for the presence and severity of lesions. Serum antibody levels to D. congolensis were monitored after vaccination and challenge. Type A and B vaccines from both strains produced some reduction in the severity of lesions when sheep were challenged with strain 1 but not with strain 2. Unvaccinated control sheep developed more severe and persistent lesions when challenged with strain 2 than controls challenged with strain 1. Serum antibody levels to the type B vaccine prepared from strain 1 were significantly higher (P less than 0.05) than antibody levels to type B vaccine from strain 2. These findings showed there was significant variation in virulence and antigenicity between these two isolates of D. congolensis.     

Inflammatory cell and immune function in Merino sheep with chronic dermatophilosis

Components of inflammatory and immunological responses were compared in 17 Merino sheep with chronic dermatophilosis (Group 1) and 15 Merino sheep that had recovered from the disease (Group 2). The functions studied included: (i) total and differential white cell counts; (ii) phagocytic function and intracellular killing by neutrophils; (iii) humoral immune response to T-dependent and T-independent antigens and to Dermatophilus congolensis. (iv) lymphocyte blastogenic responses to phytohaemagglutinin; (v) bovine serum albumen and D. congolensis antigens; (vi) quantification of T-lymphocyte subsets in skin lesions resulting after re-infection with D. congolensis zoospores. After all lesions were treated and the sheep were shorn, both groups of sheep were re-infected with D. congolensis. Both groups had similar infection rate, severity of lesions and rate of resolution after re-infection. The Group 2 sheep had significantly higher primary and secondary antibody responses to killed Brucella abortus cells than Group 1 sheep, but Group 1 sheep had higher levels of specific D. congolensis antibody throughout the trial. Neutrophils from Group 1 sheep showed a higher phagocytic rate for D. congolensis zoospores than Group 2 sheep when the zoospores were opsonised by sera from the Group 1 sheep, but there was no difference in their ability to kill ingested zoospores. Although there were some differences between the groups in the proportion of lymphocytes in lesions that reacted with monoclonal antibodies to T4, T8 and T19-19 lymphocyte markers at various times after re-infection, the sheep in Group 2 consistently had higher levels of lymphocytes reacting to a monoclonal antibody for the T6 lymphocyte antigen in skin biopsies collected 9, 15 and 21 days post-inoculation (p.i.) than did sheep in Group 1. Group 2 sheep also had higher levels of epidermal cells with immunohistochemical properties of Langerhans cells at lesion sites 15 and 21 days p.i.     

Hemolytic interactions of Dermatophilus congolensis.

The strains of Dermatophilus congolensis grew on blood agar with washed sheep erythrocytes with marked total hemolysis. In testing for hemolytic interactions they gave a significant synergistic effect of a characteristic shape with Rhodococcus equi and Streptococcus agalactiae, whereas with Staphylococcus aureus producing beta hemolysin and with Staphylococcus aureus producing delta hemolysin a simultaneous synergistic as well as antagonistic effect were observed. First of all a conspicuous inhibition of in the beta hemolysin zone began and then the hemolytic effect of D. congolensis was enhanced. A similar double reaction was also observed with Listeria ivanovii. With delta hemolysin there was an inhibition of the hemolytic effect of D. congolensis and at the same time a synergistic effect could be observed. Also D. congolensis gave a weak synergistic effect with Micrococcus lylae and Listeria monocytogenes, and a further weak antagonistic effect with alpha hemolysin of Staphylococcus aureus, Staphylococcus hyicus, Staphylococcus chromogenes and Micrococcus luteus. No interaction of D. congolensis was established with Corynebacterium pseudotuberculosis.     

Vaccination against ovine dermatophilosis

Zoospore, filamentous and soluble antigens were prepared from Dermatophilus congolensis and examined for their ability to protect sheep from challenge with D. congolensis zoospores. In 1 experiment, sheep were vaccinated with Antigens A, B and C. The number of sheep protected in the group vaccinated with Antigen B was greater (P less than 0.05) than that in the unvaccinated group after challenge. The group vaccinated with Antigen B had a higher antibody response (P less than 0.05) to Antigen B than to Antigen A or C. In a second experiment, 2 groups of sheep were vaccinated with Antigen B. All sheep in this study developed lesions after challenge, but those on the vaccinated sheep were less severe (P less than 0.05) than those on the unvaccinated sheep. The antibody response to Antigen A, 28 days after vaccination, was higher (P less than 0.05) than the response to Antigen B.     

Temporal changes in the populations of immune cells at the site of experimental Dermatophilus congolensis infection in mice and sheep

Abstract The temporal patterns of dermal immune cell influx were compared in mice and sheep, species reputedly resistant and susceptible, respectively, to infection with Dermatophilus congolensis. In both species, the response involved early mast cell degranulation, vasodilatation and an influx of dendritic cells which accumulated and apparently differentiated beneath the infected epidermis. A concomitant dermal invasion by neutrophils and T and B lymphocytes led to epidermal infiltration, particularly by neutrophils and thence to the formation of the surface scab. Hypertrophy of the epidermis also indicates keratinocyte involvement in the host response. The duration of the response, however, was considerably shorter in the mouse (about 5 days) and B cells' were the predominant lymphocyte under and adjacent to the lesion. During the more protracted response in the sheep (> 21 days), T cells, including T19 antigen +γδ T cells, outnumbered B cells. Résumé— Des modifications dans les populations des cellules immunes dans le derme sont comparées chez la souris et le mouton, espèces respectivement résistantes et sensibles à Dermatophilus congolensis. Dans ces deux espèces, la réponse fait intervenir d'abord la dégranulation des mastocytes, la vasodilatation et l'arrivée de cellules dendritiques qui s'accumulent et se différencient apparemment sous l'épiderme infecté. Une invasion concomittente dermique par des neutrophiles, des lymphocytes T et B est observée et aboutit à l'infiltration épidermique, particulièrement par les neutrophiles et pour cette raison, à la formation de croûtes superficielles. L'hypertrophie de l'épiderme indique aussi l'implication du kératinocyte dans la réponse de l'hôte. Cependant, la durée de cette réponse, est bien plus courte chez la souris (environ 5 jours) et les lymphocytes B sont les lymphocytes prédominants, sous-jacents à la lésion. Chez le mouton, la réponse est prolongée (plus de 21 jours) et les lymphocytes T, incluant les lymphocytes CD 19 et γδ surpassent en nombre les lymphocytes B. [Sasiak, A.B., Lloyd, D.H., McEwan Jenkinson, D., Kitson, S., Elder, H. Y. Temporal changes in the populations of immune cells at the site of experimental Dermatophilus congolensis infection in mice and sheep (Particularités de la population cellulaire immunitaire aux sites d'infections expérimentales à Dermatophilus congolensis chez la souris et le mouton). Veterinary Dermatology 1996; 7 : 59–66.] ResumeAn Se compararon los patrones temporales de llegada de células inmunitarias en el ratón y en la oveja, especies consideradas resistentes y susceptibles, respectivamente a la infección por Dermatophilus congolensis. En ambas especies la respuesta implicó degranulación temprana de mastocitos, vasodilatación y llegada de células dendríticas que se acumulaban y aparentemente diferenciaban bajo la epidermis infectada. La invasión dérmica concomitante por netrófilos y linfocitos T y B llevó a una infiltración epidérmica, especialmente por neutrófilos y consecuentemente a la formación de una costra superficial. La hipertrofi de la epidermis también indica la implicación de queratinocitos en la respuesta del huésped. Sin embargo, la duración de la respuesta fue considerablemente más corta en el ratón (unos 5 dias) y los linfocitos B fueron la célula predominante en la zona adyacente a la lesión y debajo de ella. Durante la respuesta más prolongada en la oveja (> 21 días), las células T, incluyendo el antigeno T19, células T γδ, superaban en número las células B. [Sasiak, A.B., Lloyd, D.H., McEwan Jenkinson, D., Kitson, S., Elder, H. Y. Temporal changes in the populations of immune cells at the site of experimental Dermatophilus congolensis infection in mice and sheep (Alteraciones temporales en las poblaciones de celulas inmunitarias en zonas cutaneas de infeccion experimental por Dermatophilus congolensis en raton y en la oveja). Veterinary Dermatology 1996; 7 : 59–66.] Zusammenfassung— Die temporären Muster des Influx dermaler Immunzellen wurden bei Maus und Schaf verglichen, Tierarten, die angeblich resistent und empfänglich speziell für die Infektion mit Dermatophilus congolensis sind. Bei beiden Spezies bezog die Reaktion eine frühe Mastzelldegranulation ein, weiterhin Vasodilatation und einen Influx dendritischer Zellen, die sich unter der infizierten Epidermis anhäuften und offensichtlich differenzierten. Eine begleitende Invasion der Dermis durch Neutrophile, T- und B-Lymphozyten führte zu einer epidermalen Infiltration, besonders durch Neutrophile und von dort an zur Bildung von Oberflächenschorf. Die Hypertrophic der Epidermis zeigt außerdem eine Beteiligung der Keratinozyten bei der Antwort des Wirtstieres. Die Dauer der Reaktion jedoch war bei der Maus beträchtlich kürzer (etwa 5 Tage) und die B-Zellen waren die vorherrschenden Lymphozyten unter und angrenzend an die Läsion. Während der mehr protrahierten Reaktion beim Schaf (> 21 Tage) übertrafen die T-Zellen einschließlich T19-Antigen und gamma-delta-T-Zellen die Anzahl der B-Zellen. [Sasiak, A. B., Lloyd, D. H., McEwan Jenkinson, Kitson, S., Elder, H. Y. Temporal chnges in the populations of immune cells at the site of experimental Dermatophilus congolensis infection in mice and sheep (Temporäre Veränderungen in den Populationen von Immunzellen an der Stelle experimenteller Infektionen mit Dermatophilus congolensis bei Maus und Schaf). Veterinary Dermatology 1996; 7 : 59–66.]