Aphanomyces invadans: The Causative Agent of the Epizootic Ulcerative Syndrome in Albino Northern Snakeheads

Abstract

A suspected epizootic ulcerative syndrome with a 50-70% morbidity rate broke out in farmed albino-type (AT) Northern Snakeheads Channa argus at Jinming farm, Chao-Yang Town, southwest China. To investigate the pathogen, diseased fish were sampled and laboratory examinations were conducted. Three specific staining methods (Grocott's hexamine silver, glycogen-periodic acid-Schiff, and modified Gram's stain) were also applied for a clear observation of fungi in tissues. Histopathological changes were studied to reveal the pathogenic mechanism. Results