Changes

Animals with advanced '''stage 3''' will appear gaunt, and the meat is no longer deemed fit for human consumption.  Once the disease is present in the herd, it is ver difficult to get rid of it.

Animals with advanced '''stage 3''' will appear gaunt, and the meat is no longer deemed fit for human consumption.  Once the disease is present in the herd, it is ver difficult to get rid of it.

==Clinical==

==Clinical Signs==

Clinical signs may also develop in older cows during times of stress; around calving for example.

There is a long incubation period between infection and the development of clinical signs; this may range from a year to several years. Animals may be affected subclinically before overt clinical signs are displayed, displaying reduced milk production, reduced reproductive performance and increased susceptibility to infection or disease.

 

In advances cases the infected animal gradually fades away and dies over the course of months.

In the later phases of infection, the disease is characterised by profuse, watery 'pipe-stem' diarrhoea and weight loss despite maintaining a good appetite. The disease is progressive and advanced cases may develop submandibular or ventral oedema due to a protein losing enteropathy.

==Pathogenesis==

==Pathogenesis==