Changes

==Clinical Signs==

==Clinical Signs==

IHN causes a '''characteristic “pop-eye” appearance''' in infected fish. The '''skin and fins may be darkened and demonstrate pinpoint haemorrhages'''. Abdominal distension sometimes occurs and the gills may be pale. Casts may be visible trailing from the vent. Fish often '''behave abnormally sporadically.'''

IHN causes a '''characteristic [[Exopthalmos - Fish|“pop-eye”]] appearance''' in infected fish. The '''skin and fins may be darkened and demonstrate pinpoint haemorrhages'''. Abdominal distension sometimes occurs and the gills may be pale. Casts may be visible trailing from the vent. Fish often '''behave abnormally sporadically.'''

Signs can also vary with species, for example Chinook salmon often show subdermal haemorrhage immediately behind their heads<ref>Amend, D. F (1974) '''Infectious Hematopoietic Necrosis (IHN) Virus Disease'''. Fish Disease Leaflet 39. ''USA: United States Department of the Interior'', pp6</ref> and sock-eye salmon smoults have clubbed/fused lamellae.

Signs can also vary with species, for example Chinook salmon often show subdermal haemorrhage immediately behind their heads<ref>Amend, D. F (1974) '''Infectious Hematopoietic Necrosis (IHN) Virus Disease'''. Fish Disease Leaflet 39. ''USA: United States Department of the Interior'', pp6</ref> and sock-eye salmon smoults have clubbed/fused lamellae.