宁夏某羊场绵羊肺炎支原体的分离鉴定及病理组织学观察

Isolation,Identification and Histopathological Observation of Mycoplasma ovipneumoniae in A Sheep Farm in Ningxia

为了确定宁夏某羊场发生一起以体温升高、咳嗽、呼吸困难为临床特征且具有传染性的疾病的病原,采集濒死病羊的病理组织,应用细菌分离培养、分子生物学鉴定、病理组织学观察及免疫组织化学分析等方法对采集的病料进行病原检测和诊断。结果显示,细菌分离培养获得3株支原体分离株,分子进化分析发现其均属于绵羊肺炎支原体,与国际标准株Y-98的序列一致性为100%。病理组织学观察显示,肺泡上皮细胞坏死、增生,支气管管腔内和肺泡腔内大量炎性细胞浸润,支气管和气管黏膜上皮细胞坏死、脱落、固有层水肿、炎性细胞浸润。对不同脏器的免疫组织化学分析显示,绵羊肺炎支原体主要集中于肺脏和气管内,且肺脏的阳性组织百分比最高,其次是支气管和气管。结合疫病的流行病学调查,该羊场所发疾病为运输应激后感染绵羊肺炎支原体导致,该病原侵染并定植于肺脏、气管及支气管上皮细胞,引起羊严重的呼吸道病症。

In order to determine the pathogen of an infectious disease characterized by fever,cough and dyspnea in a sheep farm in Ningxia,the pathological tissues of dying sheep were collected,detected and diagnosed by bacterial isolation and culture,molecular biological identification,histopathological observation and immunohistochemical analysis.The results showed that three Mycoplasma isolates were obtained from bacterial isolation and culture.Molecular evolution analysis showed that all isolates belong to Mycoplasma ovineumoniae and the sequence consistency with the international standard strain Y-98 is 100%.Histopathological observation showed that alveolar epithelial cells were necrotic and hyperplastic,a large number of inflammatory cells were infiltrated in bronchial lumen and alveolar lumen,bronchial and tracheal mucosal epithelial cells were necrotic and exfoliated,lamina propria edema and inflammatory cell infiltration.Immunohistochemical analysis of different organs showed that Mycoplasma ovineumoniae was mainly found in the lung and trachea,and the percentage of DAB positive tissue in lung was the highest,followed by bronchus and trachea.Combined with the epidemiological investigation of the epidemic disease,the disease was caused by the infection of Mycoplasma ovineumoniae after transportation stress.The pathogen infects and colonizes the epithelial cells of lung,trachea and bronchus,causing serious respiratory diseases in sheep.