The host: Meagre, Argyrosomus regious
The disease: Systemic Granulomatosis is a disease that affects farmed meagre, Argyrosomus regius. Systemic Granulomatosis is characterized by multiple granulomas in all soft tissues, which progressively may become calcified and necrotic. A granuloma appears as a nodule in the organs. Histologically, the granuloma is an organized collection of inflammatory cells that walls off the causative agent. In most cases, granulomas are caused by infectious agents, like Mycobacteria. However, Systemic Granulomatosis in meagre is believed to be a nutritional/metabolic disease and until today no pathogen has been connected to the disease.
Epidemiology: The disease affects all cultured meagre. The first granulomas appear very early in the development while the first organs affected are the liver and the kidney. As the fish grow, granulomatosis will affect almost all soft tissues of the fish.
