The results of a Court Case set to be handed down in Queensland later this week could have substantial ramifications for the future of Johne’s Disease management in Australia’s largest beef cattle state.
Two years ago, a report of three sick cows on a Central Queensland cattle stud triggered one of the largest biosecurity trace forward programs northern Australia has ever seen.
The three cows tested positive to “Mycobacterium Avium sub species Paratuberculosis”, otherwise known as ‘Johne’s’ Disease.
Until that point, and despite several previous detections of Johne’s in the north, mainly in dairy herds, Johne’s had been widely regarded as a “southern disease”, something northern producers were unaffected by and largely oblivious to.
However, the sudden imposition of quarantine restrictions across hundreds of northern cattle properties following the November 2012 detection of Johne’s at Rockley ensured Johne’s very quickly captured the attention of the northern industry.
While debate continues as to whether Johne’s poses enough of a threat to herd productivity or trade to warrant heavy-hitting control policies (see separate story), Johne’s remains categorised as a notifiable disease in Australia.
Under the national Bovine Johne’s Disease control program, agreed to by every State in Australia, Australia is divided into a series of zones according to BJD prevalence.
A series of Standard Definitions, Rules and Guidelines governs how infected (or suspected infected) herds are treated in each zone, and how cattle can move between zones, with the aim of limiting the spread from areas of high prevalence to areas of low prevalence.
The varying rules mean that producers with herds affected by Johne’s (or suspected of being infected) can have vastly different experiences depending on where they live.
For example, Victoria and Tasmania are classified as a “Management Area” where management of Johne’s is entrusted to producers at farm level. Studs in these state that wish to sell cattle into protected zones can participate in routine testing and Market Assurance Programs to demonstrate their freedom from the disease.
However, in the Protected Zone (Qld, NT and northern SA) and the Free Zone (WA), the focus is on control and eradication.
In those areas, infected herds, or those suspected of being infected, are immediately placed into quarantine and subjected to movement restrictions, restraints on trading, on-farm testing and cattle culling programs until testing proves the herd is free of the disease.
Whether producers receive compensation for these impacts, which are incurred in the name of protecting other producers and the broader industry from Johne’s disease, can also vary greatly from State to State.
WA and SA, for example, have voluntary biosecurity levies in place which enable affected producers to receive some compensation for their losses under the program.
However in Queensland, where the impact of recent detections has been greatest, there is no biosecurity levy in operation. The Queensland Government has provided around $5 million for affected producers, but the maximum available assistance per farm often amounts to just a fraction of what each producer has lost.
Dozens of properties in Queensland have spent the past two years under heavy quarantine restrictions, unable to move cattle and required to buy in feed to keep herds alive on droughted paddocks.
In that time thousands of healthy cattle have also been slaughtered under herd testing programs, the vast majority of which did not have Johne’s disease.
In January this year, a report to the Queensland Department of Agriculture, Fisheries and Forestry estimated that the eradication efforts to that point had already cost an estimated $50 million to Government and affected producers.
Different strains complicate management
The question of how Johne’s Disease should be managed has been further complicated by the emergence of three recognised strains of Johne’s that affect cattle – the bovine or cattle strain (“C” strain), the ovine or sheep strain (“S” strain) and the bison strain (“B” strain”).
All three are strains are M. Paratuberculosis or Johne’s Disease. All appear to behave in a similar way in infected cattle, all spread very slowly in beef herds and all produce similar symptoms. (One question yet to be resolved is whether cattle infected with the “S” strain have the same ability to cross-infect other cattle as those infected with the “C” and “B” strains of Johne’s).
Why are the different strains significant?
Mainly because the existing rules in cattle only deal specifically with one of those strains, the “C” strain or BJD.
The Standard Definitions, Rules and Guidelines upon which the national BJD control program is based clearly state that they apply to the “cattle strains” of Johne’s.
No specific mention is made in the SDR&Gs of the bison strain. Nor does the document deal with sheep strains. It states it “does not address infection due to sheep strains”, noting that separate guidelines are in place for Ovine Johne’s Disease (similarly the OJD guidelines do not discuss how cattle infected with the sheep strain should be managed).
Two recent significant developments have brought existing BJD management policy in Queensland into sharp focus.
The strain of Johne’s involved in the major recent Johne’s Disease detections in Queensland – centred around Rockley, Sarina and Hollins Bay – has been confirmed as the bison strain.
That finding raises an important question: was the Queensland Government within its legal rights to require hundreds of properties to submit to quarantine and culling programs under national BJD policies if those herds did not technically have BJD, but had the bison strain of Johne’s instead?
That very question is being put to the legal test in a case that is currently before the Supreme Court in Queensland, the verdict of which is expected by this Friday.
The case was brought two weeks ago by Mark Menegazzo who owns Vanrook and Inkerman Stations in the Queensland Gulf. The stations had previously bought Rockley bulls and have been under strict quarantine and movement restrictions since the November 2012 detection of Johne’s Disease at Rockley.
Legal counsel for Mr Menegazzo has argued that the national laws and rules governing BJD refer only to the cattle strain of the disease, and not the bison strain, and as a result it was unlawful to impose quarantine upon the stations.
The Queensland Government has yet to publicly clarify whether it believes cattle infected with the different strains of Johne’s should be treated equally.
Biosecurity Queensland’s response to Beef Central’s questions on the issue last week was non-committal:
“Johne’s disease is a serious wasting disease that affects a wide range of animals. It is caused by infection with a bacterium (Mycobacterium avium subspecies paratuberculosis). Of this bacterium a number of strains and sub-types exist.
“As the subject of which particular strains of the bacterium cause Johne’s disease is before the Supreme Court of Queensland, it is not appropriate for the Department of Agriculture, Fisheries and Forestry to comment any further.”
Depending on which way Justice Carmody rules, the Queensland Government is facing potentially significant ramifications.
Should he find that it was not lawful to extend BJD control efforts to herds affected by the bison strain of Johne’s, the Queensland Government may find itself facing potentially significant claims for compensation from dozens of heavily affected properties.
However, if he rules that it was lawful to extend those measures to cattle affected by the bison strain, the Queensland Government still faces another difficult decision in terms of how it deals with cattle affected by the “S” strain.
A recent incident involving bulls sent to Queensland for sale by a southern-based stud has highlighted this issue.
The stud in question has maintained an MN2 (Monitored Negative 2) status under the National Johne’s Market Assurance Program for almost 20 years, and conducts routine testing of its herd every two years.
This year, after the stud sent its annual consignment of sale bulls to a Queensland feedlot to prepare them for a sale, a female in the stud’s breeding herd at home tested positive in routine testing to the “S” strain of Johne’s. It was the stud’s first ever positive in 20 years of Johne’s testing.
When authorities in Queensland were notified of the positive test result, the sale bulls in the Queensland feedlot were placed under immediate quarantine by Queensland’s Chief Veterinary Officer (CVO).
At the same time, the stud was informed by the Chief Veterinary Officer in its own state that the national SDR&Gs, agreed to by each State in Australia including Queensland, did not apply to cattle affected by the “S” strain of Johne’s.
As a result the stud was told by its State CVO that its MN2 status would not be affected and it would be allowed to continue selling bulls into the Protected Zone, which includes Queensland.
However, the stud soon found itself in an untenable position as it waited for the Queensland Government to decide how it would view cattle affected by the “S” strain.
It is a decision with potentially large ramifications. Should the Queensland Government rule that “S” strain should be managed in Queensland in the same way as cattle with “C” strain, Johne’s management programs in the State would have to expand accordingly.
However if the Queensland Government agrees that “S” strain Johne’s is not covered under the SDR&Gs, what does that mean for the future management of cattle affected by “B” strain Johne’s, which are also not specifically referred to in the SDR&Gs?
After time passed without a firm decision on the treatment of “S” strain in Queensland, and with the cost of feeding bulls accumulating every day, the stud recently consigned its sale bulls in Queensland to slaughter. Whether it will see compensation for its losses remains to be seen.