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学士学位毕业论文猪流行性腹泻诊断与防治学生姓名：乔东剑学号：20094103015指导教师：杨隽教授所在学院：动物科技学院专业：动物医学中国·大庆2013年5月黑龙江八一农垦大学毕业论文-I-猪流行性腹泻诊断与防治摘要：猪流行性腹泻(porcineepidemicdiarrheaPED)是猪的一种急性、接触性传染病，以严重腹泻、呕吐和脱水为临床特征。各种年龄段的猪均可发病，以哺乳仔猪受害最为严重，死亡率可达95％以上。该病在世界上分布很广，呈地方性流行，危害严重。从诊断和防治等方面对PED进行了阐述，以期为防治该病提供理论依据。关键词：猪流行性腹泻；哺乳仔猪；诊断；防治DiagnosisandcontrolofporcineepidemicdiarrheaAbstract:Porcineepidemicdiarrhea(porcineepidemicdiarrhea.PED)isanacute,infectiousdiseaseofpigs,withseverediarrhea,vomitinganddehydrationforclinicalfeatures.Avarietyofageofpigsmaybethepathogenesisofsucklingpiglets,tosufferthemostserious,mortalityratemayreachabove95%.Thediseaseiswidelydistributedintheworld,areendemic,seriousharm.Fromtheaspectsofetiology,diagnosisandpreventionofPEDareexpounded,inordertoprovideatheoreticalbasisforthepreventionandtreatmentofthedisease.Keywords：Porcineepidemicdiarrhea;inpiglets;diagnosis;treatment;黑龙江八一农垦大学毕业论文-1-目录前言····················································································11病例情况··············································································12流行情况··············································································13临床症状···········································································-2-3.1哺乳仔猪·············································································13.2断奶猪、育成猪和成年猪····························································24病理变化··············································································24.1病理剖检············································································24.1.1肉眼现察··········································································34.1.2镜检············································································-3-4.2病理组织学检查·····································································35诊断··················································································35.1诊断要点············································································35.2实验室诊断··········································································35.2.1人工感染试验······································································35.2.2免疫荧光法········································································35.3.3酶联免疫吸附试验(ELISA)·························································46防治··················································································46．1预防措施··········································································46.1.1加强管理··········································································46.1.2自繁白养··········································································46.1.3免疫预防··········································································46．2治疗方法········································································-4-参考文献················································································5致谢····················································································6附录····················································································7黑龙江八一农垦大学毕业论文-2-前言猪流行性腹泻(porcineepidemicdiarrheaPED)是由猪流行性腹泻病毒(porcineepidemicdiarrheavirusPEDV)引起的一种急性、接触性传染病。20世纪70年代，英国和比利时首次报道了该病[1]。此后除美洲以外，相继在比利时、德国、加拿大、日本、瑞士等多个国家报道了该病的发生[2-5]。猪流行性腹泻已成为重要的猪病毒性腹泻病之一。哺乳仔猪，断奶仔猪和育肥猪发病率可达100％。成年母猪为15％～19％，以哺乳仔猪受害最为严重，死亡率可达95％以上，给养猪业造成了严重的经济损失。1病例情况2013年3月间，辽宁省铁岭市某猪场猪只相继发生以腹泻、呕吐、脱水和运动僵直等症状为特征的传染性消化系统疾病。其中断乳猪症状更为明显。为了确实的降低该病发生和该病对养猪业的损失，我们分析了该病的流行情况、临床症状、病理变化、诊断和防治等方面做了如下研究。2流行情况有一定的季节性，呈地方性流行。多发生于寒冷季节，夏季也有发生的报道，我国多在冬季12月至翌年2月寒冷季节发生流行。3临床症状新生仔猪潜伏期为18-24h。育肥猪约2d，自然感染潜伏期延长为5-8d。该病各种猪均易感，但仔猪临床症状最为明显、典型。3.1哺乳仔猪哺乳仔猪一旦感染，症状明显。表现呕吐、腹泻、脱水、运动值硬等症状。呕吐多发生于哺乳和吃食之后，体温正常或稍偏高，连续腹泻后体温下降。人工接种仔猪后12-20h后出现腹泻，呕吐于接种病毒后12-80h后出现。腹水和运动僵硬见于接毒后20-30h，最晚见于90h。腹泻开始时排黄色黏稠便。以后变成水样便，混杂有黄白色的凝乳块。腹泻最严重时排出的粪便几乎全部为水分。呕吐、腹泻的同时患猪伴有精神沉郁、脱水、眼窝下陷、厌食、消瘦及衰竭。症状的轻重与年龄大小有关。年龄越小，症状越重。一周以内的哺乳仔猪常于腹泻后2-4d内因严重脱水而死亡，病死率约为50％，仔猪出生后感染该病其死亡率更高[6]。3.2断奶猪、育成猪和成年猪断奶猪、育成猪和成年猪均症状较轻。其中，育成猪和断奶猪出现精神沉郁、食欲不佳、腹泻。持续4-7d后逐渐恢复正常；成年猪仅发生呕吐和厌食。4病理变化4.1病理剖检黑龙江八一农垦大学毕业论文-3-4.1.1肉眼现察病死仔猪脱水消瘦，皮下干燥、胃内有多量黄白色的乳凝块。小肠剖检变化最具特征，主要病变特征为肠管膨满扩张、外观明亮、肠壁变薄[7]；肠管内充满黄色液体或带有气体；肠系膜充血；肠系膜淋巴结水肿。4.1.2镜检小肠绒毛缩短，上皮细胞核浓缩、破碎，胞浆呈强嗜酸性变性、坏死性变化，导致肠绒毛显著萎缩、变短，绒毛高度与隐窝深度的比值由正常7：1变为3：1。4.2病理组织学检查可见小肠绒毛细胞的空泡形成和脱落，超微结构的变化。主要发生在肠细胞的胞浆，可见细胞器减少。产生电子半透明区，微绒毛终末网消失，细胞变得扁平，细胞脱落，进入肠腔。在结肠也可见到细胞变化，但未见到脱落。5诊断5.1诊断要点该病在秋冬季节易发，有明显的季节性；各种年龄的猪都可感染发病，7日龄内仔猪发生腹泻后3-4d，呈严重脱水而死亡，病死率较高，为50％-100％。成年猪则经5-7d而康复，几乎没有死亡；水样腹泻、脱水，腹泻之间有呕吐，呕吐多发生于吃食和吃奶后，年龄越小症状越重；小肠壁变薄，半透明，肠管扩大，充满半液状或液状内容物；小肠黏膜绒毛萎缩，绒毛高度与隐窝深度的比值由正常7：1变为3：1，呈弥散无边际的萎缩。5.2实验室诊断5.2.1人工感染试验选用2-3日龄不喂初乳的仔猪，喂以消毒牛乳，将病猪小肠组织与肠道内容物做成悬液。每毫升加2000IU青霉素和2000IU链霉素，室温下放置1h，接种试验仔猪，如发病，再取小肠组织做免疫荧光检测。5.2.2免疫荧光法该方法目前应用比较广泛，是检测PEDV比较可靠的特异性诊断方法。主要包括直接免疫荧光法(FAT)和间接免疫荧光法(IFAT)。首先取病猪小肠做冰冻切片或小肠黏膜抹片，风干后丙酮同定，加荧光抗体染色。充分水洗，封盖镜检，1-2h即可作出诊断结果。FAT对PEDV人工感染仔猪的检出率为91.4％，电镜观察阳性率为47.8％。而IFAT对PED阳性猪血清的阳性检出率为89％。林志雄等用适应于Vero、pKl5等传代细胞株生长繁殖的PEDV-GI株建立直接免疫荧光法。该方法不与猪传染性胃肠炎病毒、猪细小病毒、轮状病毒和大肠杆菌等发生交叉反应，具有较高的准确性。黑龙江八一农垦大学毕业论文-4-5.3.3酶联免疫吸附试验(ELISA)该方法最大的优点是可从粪便中直接检查PEDV抗原，目前应用较为广泛。该方法与电镜检查的阳性符合率为97.37％