Orkney Livestock Association

WHAT IS JOHNE'S DISEASE?

This is an incurable chronic, progressive, wasting, ultimately fatal disease that affects all ruminant species (including cattle, sheep and goats) and is caused by the bacteria "Mycobacterium Avium subspecies Paratuberculosis" which is commonly referred to as "MAP". The strains tend to be fairly species specific and if cross-infection does occur it is likely to be rarely. The organism invades the cells of the intestine wall resulting initially in thickening and then in malfunction. Affected animals usually start to lose condition and then start to scour. Death or culling usually follows within a short period. There is no treatment.

The agent is shed in large numbers in the faeces of affected animals but can also be passed on to calves via colostrums. Animals are infected by ingesting MAP and there is evidence to suggest that calves may be infected whilst in the womb. Young animals are considered most at risk from infection. Although the signs of disease can start as early as six months of age, it is more likely to found in cattle older than 18 months. In heavily infected herds most cases occur in animals aged 2 to 4 years. Infection is almost always introduced into the herd through the purchase of infected breeding stock. The progeny of confirmed cases are almost certain to be infected and so should be culled from the herd when the positive status of their dam is confirmed.

HOW DO I KNOW IF JOHNE'S IS IN THE HERD?

Due to the rather alarming symptoms explained above, you will no doubt know if you have the disease on your farm but don't assume your herd is clear if you haven't tested as we have identified numerous positive animals on holdings that have never seen a clinical case.

WHY SHOULD I TEST?

The incidence of Johne's disease is increasing every year and if we do not do something about it the problem can only get worse. Severity within herds varies from no clinical cases to farms that lose 5 or more breeding cattle every year. Identifying positive animals before they become clinical can save money as they are likely to be in reasonable condition and can be sold (not for breeding). A clinical case may be worth very little if anything.

Any member found to be selling cattle that have tested positive for breeding purposes will be in breach of the rules. We issue reminders for tests due based on previous testing dates but it is up to you to telephone your vet to book any veterinary procedures including health planning.

ACCESS TO ORKNEY ISLANDS COUNCIL FUNDING

Orkney Islands Council will pay all laboratory fees from 01 November 2008 for three years. Members will receive their test results but the Johne's testing invoice will be sent to us to claim from the Council.

RULES FOR PARTICIPATING IN OLA JOHNE'S ERADICATION SCHEME

  1. Participants in the Johne's eradication scheme must be fully paid members of Orkney Livestock Association. Orkney Livestock Association provides a CHeCS (Cattle Health Certification Standards) accredited cattle health scheme via HI Health Ltd.
  2. All samples will be tested in a CHeCS accredited laboratory.
  3. A herd is defined as cattle with the same UK herd reference number printed on at least two ear-tags. Two or more herds kept as one unit must be tested at the same time but each of their owners must be an individual scheme member to qualify for assistance.
  4. All breeding cattle over 24 months of age must be tested annually until "Johne's Disease Monitored Free" status is achieved. Then the herd is tested bi-annually, but all cull cattle or cattle moved on the holding from a holding of poorer or unknown status must be tested in the intervening years.
  5. "Johnes Disease Monitored Free" accredited status will be achieved after 2 consecutive clear tests if the herd tests clear from the start, or 3 consecutive clear tests after infection is eradicated.
  6. Johne's testing will be carried out on individual blood or individual milk samples. Samples can only be collected by a veterinary surgeon, someone designated by a veterinary surgeon or in the case of milk samples, by a milk recorder.
  7. CTS online user name and passwords must be supplied to OLA or the members own vet so that the animals tested can be checked against records held by BCMS and to allow bar code labels to be printed for the sample tubes. This is the most efficient method of testing, it reduces the risk of error compared to hand written submission forms and gives the eradication scheme increased credibility as all animals over 24 months old must be accounted for. Confidentiality is guaranteed. Passwords may be changed after the labels have been printed.
  8. Cattle that have been identified as reactors must be isolated and removed from the herd as soon as is practically possible under the advice of your veterinary surgeon.
  9. Suitable isolation facilities are in the form of pens, buildings and paddocks that do not allow contact with other livestock.
  10. The offspring from any reactor should not be retained within the herd for breeding.
  11. Cattle that have been vaccinated for Johne's disease should be tested and results interpreted the same as unvaccinated cattle.
  12. Added animals from herds that are not monitored free of Johne's disease should be tested on the farm of origin. Where this is not possible the animal must be placed in isolation and tested in accordance with CHeCS rules that at present state a blood and faecal sample should be obtained and tested. The animal can only enter the herd after it returns a negative result.
  13. Bought in bulls from non-accredited monitored free herds should be tested for Johne's Disease every six months.
  14. Equipment that can harbour the infectious bacteria such as slurry tankers, dung spreaders etc should not be shared with a herd of inferior health status.
  15. Use piped mains water rather than natural water sources whenever possible.
  16. Embryos and semen should be from donors of certified disease free status.
  17. Any breach of the above rules will lead to the member losing their status and Orkney Islands Council would have the right to recover the laboratory testing costs from the member to whom the breach of the rules applies. If challenged the decision would be arbitrated by HI Health's independent vet.