Skin and subcutaneous mycoses in tilapia (Oreochromis niloticus) caused by Fusarium oxysporum in coinfection with Aeromonas hydrophila

Subcutaneous mycoses in freshwater fish are rare infections usually caused by oomycetes of the genus Saprolegnia and some filamentous fungi. To date, Fusarium infections in farmed fish have only been described in marine fish. Here, we report the presence of Fusarium oxysporum in subcutaneous lesions of Nile tilapia (Oreochromis niloticus). Histopathologic evaluation revealed granuloma formation with fungal structures, and the identity of the etiological agent was demonstrated by morphological and molecular analyses. Some of the animals died as a result of systemic coinfection with Aeromonas hydrophila.