课件：呼吸系统疾病-猪肺炎支原体.ppt

Respiratory Disease Mycoplasma hyopneumoniae 呼吸系统疾病猪肺炎支原体,Bob Morrison DVM, MBA, PhD Swine Group University of Minnesota 明尼苏达大学,Mycoplasma hyopneumoniae 猪肺炎支原体,Transmission is primarily by direct contact with carrier swine. 传播的主要途径是与病原携带猪的直接接触。 Airborne transmission possible 经呼吸道传播使感染成为可能 Any age pig is susceptible to infection. 所有日龄的猪都易感。 Maintained in herds by sow (primarily parity 1,2) to suckling pig contact. 在猪群中通过母猪（主要是第一、二产次母猪）与哺乳仔猪 接触导致其持续存在。 Primary clinical problem is in growing pigs, 3 to 6 months old 主要临床问题出现在3到6月龄的生长猪群身上,Mycoplasma hyopneumoniae 猪肺炎支原体,Long incubation period 10 to 16 weeks 长潜伏期10-16周 Slow spread 缓慢传播 Large numbers present in the early stages of disease 大量的病例出现于疾病的早期阶段。 Disease onset is gradual coughing for weeks to months 疾病的发病是渐进性的咳嗽可持续数周到数月 Disease course is markedly affected by concurrent or secondary infections 疾病的进程明显受并发或继发感染的影响 High variation in virulence 病原毒力差异很大,What does M.hyopneumoniae do? 猪肺炎支原体有什么影响？,Colonizes tracheal epithelium 病原定居于气管上皮细胞 Destroys cilia in tracheobronchi, interferes with clearance mechanisms 摧毁气管、支气管上皮的纤毛，干扰气管的清除机制 Interferes with macrophage activity 干扰了巨噬细胞活性 Mononuclear peribronchial infiltration 单核细胞在支气管周围浸润 Produces lesions of pneumonia 造成肺炎的病变 May be severe in susceptible animals 对易感动物可能有严重后果 Produces slight ADG 导致猪平均日增重的轻微下降 Allows bacterial superinfections -Pasteurella, Strep, Actinobacillus 易发生细菌的双重感染巴氏杆菌、链球菌、放线菌,Immunohistochemical stain 免疫组化染色,Diagnosis 诊断,Gross lesions in lungs 肺部的眼观病变 well-demarcated, anteroventral, especially early in disease (7- 28 days) 界线分明、前腹叶、特别是在病变早期 Histopathology 组织病理学 Specific and recognizable lesions 特异性和可辨识的病变 Distinguish from SIV 与猪流感相区别 Detection of organism by PCR, frozen section FA, immunohistochemistry, culture 通过聚合酶链式反应检测病原、冰冻切片的荧光抗体检测、免疫组织化学、病原培养 Serology 血清学,Mhyp,Histopathology 组织病理学,Diagnosis 诊断,Culture is difficult 培养困难 Fastidious, contamination by other Mycoplasma sp. 对培养要求苛刻，易受其他支原体的污染 High sensitivity in the early stages of disease 在疾病的早期阶段有高灵敏度 Organism numbers decline over the course of the disease 病原数量在整个疾病过程中都在逐步下降 PCR nested vs non-nested 聚合酶链式反应套式与非套式 Routine, rapid 常规、快速（检验） Tracheobronchial swabs or lung lavage 支气管沾取物或肺部灌洗物 Not upper respiratory tract, nasal swabs less sensitive 不要用上呼吸道采样，鼻拭出物敏感性较差 Positive results correlated with 阳性结果与以下因素有关 Presence of clinical signs, lung lesions, eventual seroconversion 临床特征的存在、肺部病变、最终的血清学变化,Immunoflurescence免疫荧光,Diagnosis 诊断,Serology is a measure of response to natural infection or vaccination 血清学检验结果是衡量机体对自然感染或疫苗免疫应答的标准,Mycoplasma hyopneumoniae Serology 猪肺炎支原体的血清学,Serum antibody 血清抗体 Delayed and variable seroconversion, 2 to 8 wks post-infection 延迟和产生血清学变化，感染后2到8周 ELISA 酶联免疫吸附 Tween 20 ELISA 吐温20酶联免疫吸附 Whole cell membrane protein antigen 全细胞膜表面蛋白抗原 Cross-reactions with non-pathogenic M. flocculare 与无致病性的絮状支原体有交叉反应 Antibodies peak 5-7 weeks post infection. Seropositive 1 year later (25% at 8-12 months) 抗体高峰出现在感染后5-7周，1年后仍呈血清学阳性（有25保持8-12个月） DAKO ELISA DAKO酶联免疫吸附 Monoclonal antibody, species-specific epitope 74 kD protein antigen 支原体抗体，种属特异性的长度为74kD的单抗原决定簇蛋白抗原 Higher specificity 高度特异性 Both have unexpected/false positive results 都有出现非预期/假阳性结果的可能 Repeated serological tests, clinical signs, lesions at necropsy or slaughter. 重复血清学检验、临床症状、剖检或屠宰中发现的病变,Evaluating prevalence 流行状况的评估,Slaughter checks 屠宰检查 check approximately 30 pigs 检查约30头猪 as near as possible to 180 days 尽可能接近180日龄的猪 at approximately same age 在日龄基本相近的猪身上 Cough index 咳嗽的观察 observe 2 pens or 40 pigs 观察两栏或40头猪 observe for 5 minutes 观察5分钟 always same time of day 总在一天的同一时间观察 count coughs/minute 记算每分钟咳嗽次数 recognize that cough indicates onset of pneumonia, not infection and that cough does not give etiologic differentiation 辨别咳嗽是肺炎初起的反应、非感染性咳嗽和无法给出病原的咳嗽间的区别 Bacterium profile 细菌学剖面 Use PCR from nasal swabs 用聚合酶链式反应分辩鼻拭出物的细菌 Recognize that positive pigs may not be sick or infectious 要认识到阳性猪可能并没有该病或被感染,Respiratory Disease Complex 呼吸系统病的复合感染,M hyo 肺炎支原体 plus commonly detected bacteria 其他通常检出菌 P. multocida, H parasuis, S suis, Actinomyces, etc. 多杀性巴氏杆菌、嗜血杆菌、链球菌、放线杆菌等 plus commonly detected viruses 其他通常检出病毒 PRRS, PCV-2, Influenza, PRCV, etc. 蓝耳病、猪圆环病毒型、流感、伪狂犬病毒等,Lung from a pig with porcine respiratory disease complex due to PRRSV, M. hyo., and P. multocida 由蓝耳病病毒、肺炎支原体和多杀性巴氏杆菌导致的猪呼吸道病复合感染猪的肺部,Respiratory Disease Complex 呼吸系统病的复合感染,Essentially a delayed presentation of mycoplasma 必然推迟支原体的疾病表现 Usually seen in late finishing stages 通常出现在育成猪阶段的后期 This complicated form is more severe than uncomplicated enzootic pneumonia 有复合感染的情形远较非复合性感染的地方性流行性肺炎 Treatment and control are difficult 治疗和控制都很困难 Vaccinate sows 疫苗免疫母猪 Vaccinate pigs for M hyo 肺炎支原体疫苗免疫猪 Gilt acclimation, ensure that gilts have high immunity and low shedding 后备母猪的环境适应，确保后备母猪有高免疫力和低散毒率。,Serology 血清学,Serology is a measure of immune response either natural or vaccine induced. It does not predict protective effects. 血清学检验结果是衡量免疫应答的标准不论是自然感染还是疫苗诱导。但是它并不能预期疫苗的保护效果 Higher seroprevalence in lower parity sows. 在低产次母猪中有更高的血清学发病率。 Colostral antibody decay from 30 to 63 days 母源抗体的衰竭从30开始到63天结束 Colostral antibodies may provide partial protection against experimental challenge and natural disease. 母源抗体可能提供了部分保护以对抗在实验和自然疾病的感染。,Serum profile 血清学曲线 sample lots of 10 pigs of different ages 从10头猪的不同日龄采取大量血清样品 test serum for antibodies 检测血清中的抗体 determine seroconversion 确定血清学变化 recognize that seroconversion in M hyo is very delayed 认识到肺炎支原体的血清学变化的出现具有很大的时延性。,Treatment for M. hyo肺炎支原体的治疗,Tiamulin 泰妙灵 15 mg/kg x 3 days IM 15毫克/公斤体重3天 肌注 30 ppm in the feed 30ppm拌料 Lincomycin 林可霉素 10 mg/kg x 3 days IM 10毫克/公斤体重3天 肌注 100 mg/ton treatment 100毫克/吨 治疗剂量 40 gm/ton control 40克/吨 控制剂量 Tylan 泰乐菌素 8 mg/kg x 3 days IM - not licensed for treatment 8毫克/公斤体重3天 肌注不允许用于治 100 gm/ton - effectiveness? 100克/吨 治疗剂量有效？ Tylan/Sulfa泰乐菌素/磺胺类药物 100 gm/ton tylosin & 100 gm/ton Sulfamethazine 100克/吨泰乐菌素和100克/吨磺胺二甲基嘧啶 Tetracyclines 四环素类 400gm/ton Chlortetracycline 400克/吨金霉素 20 mg/kg Oxytetracycline IM 20毫克/公斤体重土霉素 肌注 50mg/kg Tetracycline HCI PC 50毫克/公斤体重盐酸四环素 Very good for prophylaxis 有很好的预防效果,Treatment for P. multocida 多杀性巴氏杆菌的治疗,Sulfas 磺胺类药 Sulfadimethoxine 磺胺二甲氧基嘧啶 Sulfamethazine - residues! 磺胺二甲基嘧啶残留问题！ Sulfathiazole 磺胺塞唑 Given in drinking water 3-5d 饮水投药3-5天 Lincomycin -no direct effect on Pasteurella 林可霉素对巴氏杆菌没有直接作用 Spectinomycin 壮观霉素 10 mg/kg IM 10毫克/公斤体重 肌注 Tetracyclines - See Mycoplasma 四环素类见支原体章节 Ampicillin 氨苄青霉素 10 mg/kg IM 10毫克/公斤体重 肌注 Trimethoprim/Sulfa 磺胺增效剂/磺胺 In drinking water-not labeled in USA 饮水投药美国没有给药标准,Control 控制,Risk factors 风险因素 Presence of virulent organism 强致病力病原的存在 Immunosuppressive viruses 免疫抑制性病毒 Animals from many sources 多来源动物 Continuous flow production 连续流水线生产 Excessive density 过高饲养密度 Open pen partitions 开放式栏舍分