Changes

== Clinical Signs  ==

== Clinical Signs  ==

Clinical signs in '''cattle''' are severe and include necrotising lesions in  the upper respiratory tract and eye: conjunctivitis and corneal oedema / opacity (keratitis or "blue eye" - characteristic feature). Pyrexia and diarrhoea with severe oculo-nasal discharge and inappetance also occurs. The animal will appear dull with ulcers on its muzzle, which exude a brown exudate. These may spread to the rest of the face and occasionally the whole body. There may also be ulcers on the tongue, dental pad, and cheeks that regularly become secondarily infected. [[Lymhocytes - Introduction|Lymphocyte]] proliferation to viral antigen in the blood vessels of lymph nodes, spleen lungs, liver and kidneys progresses until death occurs. The lymph nodes eventually become completely replaced by [[Lymph Nodes - Anatomy & Physiology#Follicles|lymphoblasts]], which is a similar pathogenesis to [[lymphosarcoma]]. There may also be vasculitis with medial necrosis of blood vessels throughout body with infiltration of walls of vessels by lymphocytes.  

Clinical signs in '''cattle''' are severe and include necrotising lesions in  the upper respiratory tract and eye: conjunctivitis and corneal oedema / opacity (keratitis or "blue eye" - characteristic feature). Pyrexia and diarrhoea with severe oculo-nasal discharge and inappetance also occurs. The animal will appear dull with ulcers on its muzzle, which exude a brown exudate. These may spread to the rest of the face and occasionally the whole body. There may also be ulcers on the tongue, dental pad, and cheeks that regularly become secondarily infected. [[Lymphocytes - Introduction|Lymphocyte]] proliferation to viral antigen in the blood vessels of lymph nodes, spleen lungs, liver and kidneys progresses until death occurs. The lymph nodes eventually become completely replaced by [[Lymph Nodes - Anatomy & Physiology#Follicles|lymphoblasts]], which is a similar pathogenesis to [[lymphosarcoma]]. There may also be vasculitis with medial necrosis of blood vessels throughout body with infiltration of walls of vessels by lymphocytes.

== Diagnosis  ==

== Diagnosis  ==