鸡毒霉形体人工感染肉用仔鸡后呼吸系统的病理形态学观察

７日龄健康肉用仔鸡气囊接种鸡毒霉形体（ＭＧ）ＨＳ２心株，３～５ｄ后出现典型的ＭＧ感染症状，其呼吸系统（主要为气管、肺及气囊）发生一系列病理组织学变化。采集感染鸡及对照鸡的气管经固定、脱水、临界点干燥、镀金后置于扫描电镜下观察，可见感染鸡气管粘膜明显水肿，纤毛部分或全部脱落等，而对照组鸡气管则无任何病变；光镜下可见感染鸡的气管粘膜水肿增厚１～２倍，粘膜下层单核白细胞聚集，其间有数量不等的淋巴细胞集团，粘液细胞减少或消失；气囊粘膜水肿增厚，有淋巴细胞增生而形成的串珠样结构；肺组织中有淋巴细胞增生形成的结节病灶，而对照鸡呼吸系统的组织切片在光镜下无任何异常变化。

Pathomorphological Observation on the Respiratory Systems in Broilers Experimentally Infected with Mycoplasma Gallisepticum

Healthy 7dayold broiler chicks were inoculated with Mycoplasma gallisepticum (MG) strain HS2 heart by a route of thoracic air sacs. 35 days after the infection, typical MGinfected symptoms occurred. Serial pathohistological lesions appeared in respiratory system (i.e. trachea, lung and air sac). Scanning electron microscopy (SEM) method was performed to observe pathological damages in tracheae of infected and control chickens subjected to fixing, dehydrating, critical point drying and goldcoating. The apparent edema of tracheal mucosa and the partial or whole exfoliation of cilia were seen in experimental infected groups, but no morphological changes were observed in control groups. Examination of infected chickens respiratory system by light microscopy (LM) showed 1 to 2fold increase in tracheal mucosal thickness induced owing to aggregation of monocytes underneath mucosa and some clump of lymphocytes, decreasing disappearing of mucous cells, edema and increased thickness in air sacs mucosa and monilated structure owing to lymphocytes hyperplasia, local pustules in lung owing to lymphocytes hyperplasia. However, no abnormal changes were detected in respiratory system of control groups by light microscopy.