Death of a female angel breeder fish (Pterophyllum scalare) due to a massive thrombosis in renal vein and presence of tumoral mass in renal tissue

Objective: To determine the cause of death of angel breeder fish (Pterophyllum scalare) with clinical sign of abdominal swelling. Method & Materials: In September 2008, one female angel breeder fish died with only clinical sign of abdominal swelling was referred to bacteriology lab of Veterinary Faculty of Urmia University. The dead fish underwent autopsy in sterile condition in order to prepare bacterial culture from ascetic fluid, liver, and kidney. Tissue samples of internal organs were fixated in 10% formalin for pathologic analyses. They were stained with Haematoxylin-Eosin method. Results & Conclusion: No bacteria growths were seen on the culture media after 48-72 h incubation. Microscopic observation showed fatty degeneration of liver and dissociation of hepatocells. In renal tissue severe haemorrhage along with congestion were observed. Renal tubules also showed severe degeneration and necrosis. There was a massive thrombosis inside greater renal vein and small thromboses in lesser renal veins. In a renal tissue there was a tumoral mass. The resultant ascites has been due to the tumoral mass and the thromboses. There were no pathologic abnormalities in the other organs. The causative agent of such severe thromboses and tumoral mass formation needs further investigations.