黄颡鱼(Pelteobagrus fulvidraco)爱德华氏菌(Edwardsiella ictaluri)感染的动态病理学及病原分布研究

DYNAMIC PATHOLOGY AND PATHOGEN DISTRIBUTION STUDY ON YELLOW CATFISH PELTEOBAGRUS FULVIDRACO INFECTED WITH EDWARDSIELLA ICTALURI

采用病理形态学方法与免疫组化法进行了黄颡鱼(Pelteobagrus fulvidraco)爱德华氏菌(Edwardsiella ictaluri)感染的动态病理学与病原分布研究。结果表明,感染鱼主要临床特征为游动缓慢,旋游,体表出血,腹部膨大,腹腔内充有淡黄色或含血的腹水,肝、脾与肾肿大,出血;病理组织学上,感染后8—12h,肝细胞空泡变性和间质性肾炎;24h后肝出现局灶性坏死,肾小管上皮变性和更严重的间质性肾炎,脾出血和淋巴细胞坏死;48h后,肝、脾、肾坏死更严重,致感染鱼死亡。感染后8h,在肝脏检测到病原菌阳性信号,12h后,在肝、肾、脾中检出阳性信号,48h后,在肝、肾、脾、心、脑、鳃、肠道等都检出阳性信号,表明爱德华氏菌腹腔注射感染黄颡鱼首先侵袭肝、肾、脾,然后是心脏、脑、鳃、胃肠等。

Using pathologic and immunohistochemical method, we studied the dynamic pathology and pathogen distribution of yellow catfish （Pelteobagrus fulvidraco） that infected with Edwardsiella ictaluriby intraperitoneal injection. Syndromes of infected fish included slowed / twisted swimming, external / internal bleeding / swollen, yellowish / bloody ascites in the abdominal cavity, etc. Histopathologically, after 8—12h of infection, vacuolar degeneration and interstitial nephritis were observed in liver and the kidney; after 24h, focal necrosis appeared in liver, renal tubular epithelial cells degeneration and more severe interstitial nephritis were founded in kidney, followed by hemorrhages on spleen and lymphocyte necrosis; after 48h, liver, spleen, and kidney showed more serious necrosis, causing death of infected fish. E. ictaluricould be detected positive in the liver in 8h of infection, and in the liver, kidney and spleen in 12h, and extended into heart, brain, gills and gut in 48h. It revealed that the pathogen invaded the liver, kidney, spleen first, and then the heart, brain, gills and gastrointestinal tract.