Johne's Disease
18th September 2007
Category: Health Fact Sheets
Johne‘s disease (pronounced ""yo-knees"") 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.
Signs are rarely evident until two or more years after the initial infection, which usually occurs shortly after birth. Animals are most susceptible to the infection in the first year of life. Newborns most often become infected by swallowing small amounts of infected manure from the birthing environment or udder of the mother. In addition, newborns may become infected while in the uterus or by swallowing bacteria passed in milk.
Although not a notifiable disease in Great Britain, Johne’s disease is notifiable in Northern Ireland.
If you suspect Johne’s disease to be present in your herd, there are a number of control measures which can be incorporated in your farm health plan.
These include:
1. Remove diseased cattle from the herd as early as possible. Do not breed from their offspring.
2. Keep your cows and their environment as clean and free from faecal contamination as possible, especially during the calving period and for the first three months of the calves’ lives.
3. Prevent faecal contamination of feed.
4. Provide mains water, keep troughs clean and fence off other water sources, particularly areas of stagnant water.
5. Spread dung or slurry on arable land. If this is not possible, delay grazing young cattle on slurried pasture as long as possible and, if practical, for at least one year.
6. Avoid co-grazing or sequential grazing with other livestock that may be infected and control rabbits.
7. Keep a closed herd, but if it is essential to buy in cattle, try to obtain stock from sources that can demonstrate they are tested free from Johne~s disease.
For more information, visit www.defra.gov.uk, or order further copies of the Guidance Notes from Defra publications 0845 955 6000. You can also download the Guidance Notes from the Defra website.