Bovine Johne's Disease
Bovine Johne's Disease (BJD) is a chronic, incurable disease of adult cattle caused by the bacteria Mycobacterium paratuberculosis. Symptoms include diarrhoea, reduced milk production, weight loss and eventually death.
The disease is mainly spread through ingestion of contaminated feces. Infection is usually acquired in calfhood but generally no clinical signs are seen until animals are at least four years old. It is difficult to reliably detect infection in live animals, particularly in the early stages of the disease.
The keys to controlling spread in a herd are preventing exposure of susceptible young calves, introducing only low-risk cattle and targeted testing and culling of animals to reduce shedding of Mycobacterium paratuberculosis into the environment.
Managing the risk in Australian dairy herds
Understanding more about BJD and how to manage the risk is an important first step. Whether you want to be part of a formal control program or to just minimise the risks in your own herd, there are a number of steps you can take.
BJD has been managed through various control programs in Australia. Since 2016, BJD has been voluntarily managed.
The revised Johne’s Disease Dairy Score (2019) was developed by the Australian Dairy Farmers (ADF) in consultation with industry veterinarians, Animal Health Australia and State Dairy Farming Organisations to:
- Provide an easily interpreted score for dairy farmers to profile their risk of BJD
- Enable farmers to introduce or sell dairy animals with some assurance as to their BJD status
- Clarify how vaccination can be used to control and reduce risk of BJD.
You can access the latest information on the new arrangement and a summary of requirements to achieve and maintain the score levels in the Johne's Disease Dairy Score 2019 (PDF, 1.1MB)
More information to assist includes:
Check with your state’s agriculture department for any regional information.
These publications contain important information and guidelines for best practice:
Dairy farm guidelines for BJD control: Best practice recommendations for managing bovine Johne's disease in Australian dairy herds (PDF, 1.1MB)
A booklet for dairy farmers containing best practice recommendations for managing BJD in Australia.
Dairy BJD Technotes: Best practice recommendations for managing bovine Johne's disease in Australian dairy herds (PDF, 4.1MB)
A technical booklet for veterinarians and herd advisers discussing best practice recommendations for managing BJD in Australia.
New approach to Bovine Johnes Disease (PDF, 144KB)
Other dairy strategies to manage BJD
The control of BJD in Australia is implemented according to a strategic plan. The dairy industry is promoting the use of the National Dairy BJD Assurance Score and adoption of hygienic calf rearing practices through the 3-Step Calf Plan and/or the Johne's Disease Calf Accreditation Program (JDCAP).
The 3-Step Calf Plan
Limiting calf contact with adult cattle and sources of manure minimises the risk of BJD and many other diseases including calf scours. This is the basis of the 3-Step Calf Plan. Implementing the 3-Step Calf Plan is an excellent way to reduce the risk of BJD in a herd and improve the overall health of calves.
3 Steps to minimise BJD risk in your herd (PDF, 1167KB)
All dairy companies have included the 3-Step Calf Plan in their on-farm quality assurance programs to support BJD control and good calf health. This brochure explains in more detail the three steps to minimise BJD risk in your herd and other best practice recommendations.
The following information may prove useful to understanding more about BJD and how it is being managed in Australia and overseas.
Australian BJD information:
International Links on BJD:
Extensive Bovine Johne's Disease information site run by the University of Wisconsin
International Association for Paratuberculosis