鸭源多杀性巴氏杆菌在人工感染雏鸭体内的动态研究  

Pathogenesis of Pasteurella multocida in artificially infected ducklings

作　　者：都启晶[1] 蒋文灿[1] 彭广东[1] 李淑娜[1] 郑维维[1] 刘义铃[1] 刘巍申[1] 

机构地区：[1]四川农业大学动物医学学院,四川雅安625014

出　　处：《中国预防兽医学报》2008年第9期699-704,共6页Chinese Journal of Preventive Veterinary Medicine

摘　　要：为探索多杀性巴氏杆菌在雏鸭体内的动态病理变化,用小鼠复壮鸭源多杀性巴氏杆菌,经测定其滴鼻途径的LD50=1×10-4.5/0.2mL,口服途径的LD50=1×10-2.375/0.2mL。用100LD50剂量,以口服、滴鼻途径分别感染雏鸭,于感染后6h、12h、18h和24h取心、肝、肺、肾及胸腺进行组织活菌计数。口服和滴鼻感染后12h,从胸腺、肝、心、肺检测到生长繁殖的病原菌,18h从口服感染组的肾脏检出目标菌,24h从滴鼻组的肾脏检出目标菌。口服感染12h,胸腺中菌数最高,达5.33×103CFU/g,依次是肝、肺、心、肾。滴鼻感染12h,肺中菌数最高,达5.00×103CFU/g,依次是胸腺、肝、心、肾。24h均以胸腺菌数最高。表明检测体内鸭巴氏杆菌抗原或分离病原菌,首选器官是胸腺和肺,其次是肝、心。同时取心、肝、肺、肾、脾、胸腺、法氏囊、腺胃和十二指肠制作病理切片。消化道途径感染出现病变的最早时间是侵入后6h,呼吸道途径感染出现病变的时间小于6h。口服途径感染雏鸭后6h,各器官都表现以充血为主要特征的轻微病理变化,6h～12h表现以细胞肿胀、开始细胞变性为特征的病理变化。12h～18h表现细胞变性加剧,开始核浓缩、核碎裂为特征的病理变化。18h～24h表现核浓缩、核碎裂加剧,细胞溶解的细菌损伤病理,以及淋巴细胞浸润、免疫器官网状内皮细胞增生相伴的免疫损伤。滴鼻途径的病理变化与口服途径相似,但病理进程有所提前。鸭多杀性巴氏杆菌对胸腺、脾、法氏囊等免疫器官造成病理损伤,以胸腺和脾脏的损伤较为严重。To investigate the pathogenesis of Pasteurella multocida. Healthy ducklings were infected by oral or nose infection. Heart, lever, lung, kidney and thymus were collected at 6, 12, 18 and 24 hours after infection for bacteria isolation and histological analysis. The results showed that the LD50 of nose-infection was much higher than that of oral infection. The highest bacteria counts were recorded in thymus and lung 12 hours after oral or nose infection. The thymus had the highest bacteria count for both oral-and nose-infected ducklings at 24 hours infection. These results indicated the thymus and lung were the organs of choice for detecting Pasteurella multocida and isolating pathogenic bacteria. Histological study showed that all organs had congestion at 6 hours after oral infection, followed by swelling, degeneration, condensation and fragmentation of nucleus, lymphocyte infiltration and the proliferation of endothelium. Pasteurella multocida also caused immune organ injury, especially in thymus and spleen.

关 键 词：鸭源多杀性巴氏杆菌 感染雏鸭 致病力 细菌动态繁殖 动态病理 

分 类 号：S852.615[农业科学—基础兽医学]