Johnes Disease

JOHNES DISEASE DETECTION IN WA

At the time of printing, WA Angus received an invitation from Minister MacTiernan MLC, Minister for Regional Development; Agriculture and Food; Hydrogen Industry, to a meeting to discuss how best to control and manage BJD in WA. We thank the Minister for this opportunity.

Thursday, 28 October 2021

INFORMATION FOR MEMBERS AND PRODUCERS Johnes Disease Detection in Western Australia

Good morning members and producers: Following the detection of Johnes Disease in Western Australia, the following advice has been issued by WA's Chief Veterinary Officer.

Cattle Council and its member organisations are seeking further information from the Western Australian Department of Primary Industries and Regional Development and will provide further updates to producers as information comes to hand. The advice from the WA CVO follows:

Biosecurity information: Johne’s disease in sheep and cattle in Western Australia

Dear WA cattle and sheep industry stakeholders I am writing to you about Johne’s disease (JD) in sheep and cattle and to advise of the decision by the Department of Primary Industries and Regional Development (DPIRD) and WA cattle industry to reduce regulatory controls for JD cattle strain (C-strain) in WA.

Definition of JD

JD is defined as infection with any strain of Mycobacterium avium subsp. paratuberculosis, which includes sheep (S-strain), cattle (C-strain) and bison (B-strain). All states and territories use this definition to certify for live animal export certification for JD and it is also used for national industry assurance programs such as the Johne’s Beef Assurance Score (JBAS) and Johne’s Disease Dairy Score (JDDS). The S-, C- and B-strains can affect more than one species, not just the species they are named for. Therefore, the detection of JD in either your cattle or your sheep may impact either or both species’ access to some live export markets and impact industry assurance programs.

Why WA is reducing its JD regulation

DPIRD has previously maintained interstate border conditions to reduce the risk of entry of JD (Cstrain) at the request of WA industry, as JD (C-strain) was not known to be present in WA. JD (C-strain) has now been confirmed in a homebred cow on a property in southern WA. DPIRD carried out an investigation that determined: •JD C-strain has been present on the property at a very low level for several years. •The original source of the infection was unable to be determined and may be another WA property. When considering whether JD C-strain could be eradicated, DPIRD and WA industry took into account the following: •The large number of cattle that had moved from the property to multiple properties across the state •the limitations of the available test and length of time it would take to determine which of the trace forward properties were positive or negative for C-strain, and recognising that JD (C-strain) would only be present in a small number of cattle

• the large number of properties that would be placed under surveillance and regulatory controls for up to five years while their status was determined, and the social and financial impacts on those properties, most of which will not be infected •the estimated cost to industry of attempting eradication and the low likelihood of success, given the original source of the infection cannot be determined and may have come from another WA property •that sheep strain of JD is endemic in WA in sheep and is increasingly being detected in cattle •that export markets and industry assurance schemes do not differentiate between the different strains of JD. Following assessment of these factors, DPIRD and WA industry agreed it was not technically feasible or economic to eradicate JD (C-strain) from WA. As a result, regulatory controls for JD C-strain in WA will be reduced. The controls will align with: •the national approach to JD and •WA’s management of S-strain in cattle and all strains of JD in sheep.

What JD regulation will change:

•WA properties confirmed to have JD (C-strain) will not be subject to disease regulatory instruments by DPIRD. DPIRD will not require destocking of these properties. •Approval is being sought for registration of the Silirum JD vaccine for cattle, for use by veterinarians in WA. •Interstate import conditions for JD will be amended after a transition period to enable WA producers to make informed decisions about the likelihood of introducing JD onto their property via interstate livestock movements.

What JD regulation will stay the same:

•Under the Biosecurity and Agriculture Management Act 2007 (BAM Act), detection of any strain of JD in any species in WA must continue to be reported, in order to support certification for live export markets. As a reportable disease, anyone with a suspicion or detection of JD in livestock must report it to a BAM Act authorised inspector, such as a DPIRD Field Veterinary Officer. •Property of origin certification for live animal export markets has not changed. JD is infection with any strain of Mycobacterium avium subsp. paratuberculosis, which includes sheep (S-strain), cattle (Cstrain) and bison (B-strain). Properties are certified at a property level on their status in relation to any of these strains. (Note that the national JD zones previously used for interstate trade were removed in 2016.)

National industry assurance schemes have not changed

WA producers are still able to participate in voluntary risk-profiling industry assurance schemes for cattle, such as the JBAS and JDDS, and market assurance programs for sheep.

How will these changes affect my business?

DPIRD recommends producers consider what impact JD (any strain) might have on their business and review their biosecurity accordingly. DPIRD has collated resources to assist producers, including information on JD, on-farm biosecurity practices, risk mitigation (including biosecurity plan templates and checklists to consider in planning, assessing and managing risk), and national industry assurance programs in the following webpages:

•JD in cattle: management in WA •JD in cattle: frequently asked questions •JD in cattle: regulatory controls •JD in sheep •JD in sheep: biosecurity practices and management options

Please contact your regional DPIRD field veterinary officer or private veterinarian if you require further information. Yours sincerely Dr Michelle Rodan, WA Chief Veterinary Officer Department of Primary Industries and Regional Development