Changes

The '''reddening of the throat and mouth''' that give the disease its name are caused by '''subcutaneous haemorrhage''' and are common but not always present. This can progress to '''erosion of the jaw and palate if untreated'''.

The '''reddening of the throat and mouth''' that give the disease its name are caused by '''subcutaneous haemorrhage''' and are common but not always present. This can progress to '''erosion of the jaw and palate if untreated'''.

Affected fish also have generally '''darkened skin and fins''' with haemorrhagic lesions around the '''gill tips, vent and fins and are lethargic and inappetant'''. They may have a '''distended abdomen''' leading to a “pot-bellied” appearance. Fish are often pale around the gills and may demonstrate '''exopthalmos''' with periorbital oedema. They are anorexic and may swim close to the surface.

Affected fish also have generally '''darkened skin and fins''' with haemorrhagic lesions around the '''gill tips, vent and fins and are lethargic and inappetant'''. They may have a '''distended abdomen''' leading to a “pot-bellied” appearance. Fish are often pale around the gills and may demonstrate [[Exopthalmos - Fish|'''exopthalmos''']] with periorbital oedema. They are anorexic and may swim close to the surface.

'''Mortalities are frequent and variable. They may occur in small fry with virtually no preceding signs'''.<ref>Kawula, T. H., Lelivelt, M. J., Orndorff, P. E (1996) '''Using a new inbred fish model and cultured fish tissue cells to study '''Aeromonas hydrophila''' and '''Yersinia ruckeri''' pathogenesis'''. ''Microbial Pathogenesis'', 20(2):119-125; 12</ref> Losses of 15% over a cycle are not uncommon and can reach 90% on small scale units.

'''Mortalities are frequent and variable. They may occur in small fry with virtually no preceding signs'''.<ref>Kawula, T. H., Lelivelt, M. J., Orndorff, P. E (1996) '''Using a new inbred fish model and cultured fish tissue cells to study '''Aeromonas hydrophila''' and '''Yersinia ruckeri''' pathogenesis'''. ''Microbial Pathogenesis'', 20(2):119-125; 12</ref> Losses of 15% over a cycle are not uncommon and can reach 90% on small scale units.