Managing Johne's disease in sheep on infected properties

The Ovine Johne’s disease management program is supported and funded by the SA Sheep Industry Fund.

Managing OJD on infected properties

If Ovine Johne’s disease (OJD) is detected on a property, the below procedure is followed, either through voluntary abattoir surveillance or disease investigation:

1. Post mortem findings are confirmed by laboratory testing of gastrointestinal tract samples, and/or pooled faecal testing of a screening test High Throughput – Johne's PCR (HT-J PCR), on high risk mobs of sheep on the property.
2. If Johne's DNA is detected in the HT-J PCR screening test, a bacterial culture is performed to isolate and grow the bacterium to confirm the disease status. The bacterial culture takes 12-16 weeks before results are available.
3. A property disease management plan (PDMP) can be developed by producers through PIRSA’s One Biosecurity program to manage the risk of disease spread and economic losses. The PMDP will detail a timeline to manage the disease and a best practice vaccination plan, strategic grazing and trading practices. 
   • Orders under the Livestock Act 1997 may be placed on the property if producers fail to undertake reasonable measures to manage OJD risks to the industry.
4. Direct neighbours of infected properties are considered at risk of OJD. As part of meeting their biosecurity obligations, infected producers should notify their neighbours and other producers of the change to their OJD status. When a producer chooses to notify their neighbours or producers who they have sold stock to, PIRSA can provide support. We will talk to individual producers and/or hold community meetings to advise on undertaking risk assessment and best practice disease management. Upon written request from the infected producer, PIRSA can undertake notification on their behalf.
5. Best practice trading options for infected properties may include:
   • direct sale for terminal slaughter at abattoirs
   • direct sale for feedlots
   • approved vaccinates
   • interstate sale (producers must check the entry requirements for livestock to that state)
   • all sheep must be accompanied by a National Sheep Health Declaration that should indicate the suspect or infected status of the flock.
6. Properties wishing to clear their infected or suspect status will need to undertake a clearance test or destocking program:
   • the property can undergo a clearance test a minimum of 2 years after the last detected infected animal has been destocked and sheep are approved vaccinates - a successful clearance test is when the OJD bacteria is no longer detectable on a Pooled Faecal 350
   • a destocking program approved by the Chief Veterinary Officer has been completed.
7. Time frame for properties to reach a low risk or undetectable status will depend upon:
   • length of time breeding ewes and their ewe progeny (from initial disease detection) are retained in the flock – each cast for age will result in a corresponding delay in the clearance testing date
   • delays also occur when replacement sheep purchased are not approved vaccinates.

Vaccination to minimise OJD risk

The Gudair vaccine is available from most agricultural suppliers. It should be used as a preventative risk management tool rather than waiting until suspicion or detection of disease occurs.

Producers in high risk areas or with high risk businesses should consider incorporating Gudair vaccine in their regular animal health program as they do with other vaccines and intestinal parasite treatments to prevent disease occurring.

More information

• Farm management strategies – fact sheet (PDF 290.2 KB)
• Property detections and next steps – fact sheet (PDF 165.8 KB or DOCX 156.9 KB)