Introduction
Johne's disease is an infectious wasting condition of cattle and other ruminants caused by Mycobacterium avium subspecies paratuberculosis, commonly known as Map. It is closely related to the organism that causes tuberculosis.
The disease progressively damages the intestines of affected animals, and in cattle this results in profuse and persistent diarrhoea, severe weight loss, loss of condition and infertility. Affected animals eventually and inevitably die.
In dairy herds, the presence of Johne's disease will significantly reduce milk yields well before other signs of the disease can be found. Johne's disease is not a notifiable disease in Great Britain (England, Scotland and Wales), but it is notifiable in Northern Ireland.
Further Information
For more in depth information on Johne's disease, guidance on how to spot it, prevent it and deal with it; please see the published Johne's disease advisory notes.