INTRODUCTION AND BACKGROUND OF THE
Johne’s Disease (Cattle) Farm Biosecurity Plan Template
If you have read this introduction and would like a copy of the Biosecurity Plan Template to fill in and apply to your property, please contact Gayndah Veterinary Surgery directly on (07) 4161 1404. The Template is prepared as a tool to assist cattle producers in the North Burnett in Qld to manage the risks of Bovine Johne’s Disease in their herds. Specifically, it is for producers exporting cattle to WA from the North Burnett as provisional Johne’s Disease Beef Assurance Score (JD-BAS) 7.
From the 1st of July 2017, all Qld properties lapsed to JD-BAS Score 6 unless they met the requirements for JD-BAS 7 (or 8) by the 30th of June 2017. Properties then lapsed to a Score 0 at the end of September 2017 if they still had not developed a documented biosecurity plan. WA will only accept cattle from JD-BAS 7 or higher, and so without meeting the requirements of JD-BAS 7 producers are unable to export cattle to WA until they have achieved JD-BAS Score 7 again. To move from JD-BAS 0 to 7 involves several years (at least 5) of continuous work and expensive testing.
Producers currently exporting to WA perform yearly Check Tests (CT) where faecal material from 50 animals over 2 years age is collected and sent to the Biosecurity Sciences Laboratory at Coopers Plains in Brisbane and tested for JD organisms by PCR (looking for DNA from JD). JD-BAS Score 7 requires a property to perform triennial (once every 3 years) Check Tests. The WA requirement for 12 monthly Check Tests exceeds this. The other requirement to maintain JD-BAS 7 is the preparation and implementation of a property biosecurity plan, which must be reviewed annually by a veterinarian.
The template does NOT cover areas of animal disease and pests apart from Johne’s Disease in Cattle. As such, it should be regarded as a detailed appendix to a more general, and less detailed, farm biosecurity plan. JD-BAS 7 requirements for the biosecurity plan include veterinary consultation when setting up the biosecurity plan, and an annual review by a veterinary advisor.
This template has two objectives:
- meeting the requirements of a biosecurity plan for JD-BAS 7, and
- preventing the entry of JD into properties exporting to WA.
Most properties exporting cattle to WA are stud Brahman and Droughtmaster bull producers, and consequences of JD being diagnosed on these properties will include loss of market access in WA for stud bulls. This template may not be suitable for properties not exporting to WA, as consequences of an incursion are not nearly so severe in the short term, and JD, if it does infect a farm, should be able to be eradicated with a small effort and careful management over a short time (2 -5 years). At least part of this expectation of ease of eradication in non-WA exporters is based on the climate and typical management practices of beef cattle properties in the North Burnett, and assumes producer awareness of JD and testing of suspect animals.
It should be noted that this biosecurity plan template CANNOT guarantee the prevention of JD entering a property. If complied with, it should reduce the risks of JD incursion to negligible levels, and part of the plan is to monitor for such an incursion and contain it quickly if found.
Background of Johne’s Disease in cattle in Queensland.
Johne’s Disease was diagnosed a few years ago in a Brahman stud herd in Qld, and it was suspected that the disease had been present at low levels for some time. JD was a notifiable disease at the time, and DPI staff instituted trace-forward investigations, identifying several properties ‘downstream’ in the cattle movements which were also infected, although at low levels.
The organism is generally considered to spread in cold, wet weather, and the main source of infectious material is faeces from affected animals. In low-prevalence situations, it can take up to 2 years or more for an infected animal to begin shedding significant numbers of organisms in faeces. Cattle older than 18 months are considered to be somewhat more resistant to infection than animals under 18 months, so typical management plans mainly rely on reducing contact of calves with faeces of adult animals. In southern dairy herds this is achieved by ‘calf snatching’ where calves are removed from their mother within 24 hours of birth. For practical reasons this is impossible in beef herds in the North Burnett.
Rainfall in the North Burnett is typically a summer rainfall pattern, with cold, dry winter weather and some frosts. The main growing season for pastures is through the summer months, associated with (and very much limited by) rainfall or lack thereof. This means that faecal material is typically in pats, rather than sloppy as in dairy herds. Sloppy manure is associated with lush green feed during rainfall, and mostly in the first few weeks of pasture growth. Due to the need to limit stocking rates to levels sustainable year-round, in these times of plentiful feed cattle tend to spread out and manure is quickly covered by pasture growth. Dung beetle activity is high, pats of manure are broken down within days, and exposure of calves to faecal material from adults other than their mother is quite limited. Pats are usually broken down quickly by dung beetles unless the weather is too dry for dung beetle activity, in which case the pats dry to hard lumps within days.
These factors mean that JD in the North Burnett is unlikely to spread quickly, if it does at all. If it does spread, factors favourable to it include:
- Prolonged wet winter weather (although without the correct pastures for winter growth, sloppy manure for long periods is unlikely).
- Management practices that group calves with adults other than their mother for prolonged periods (feeding grain, silage etc in small yards, camping behaviour around supplement feeders)
- High stocking rates on irrigated, improved pastures (where faecal material does not dry)
- Entry into the herd of JD carriers shedding high numbers of organisms.
- Failure of dung beetle populations to break down pats of manure during wet weather.
Given that, until recently, beef herds in Queensland were JD free, or at least well controlled, the risk of introducing JD onto a property by purchasing cattle born and raised in Qld is negligible. This may not be the case in a few years. Simply ensuring good boundary fences and only purchasing cattle from other JD-BAS 7 properties should be all that is required to prevent incursions. We should mention effluent/manure/run off contamination of waterways here. Overseas, and in southern Australia, this is a big issue, and is the reason waterways/dams/etc. are supposed to be fenced off from stock as part of a JD biosecurity plan, with water supplied through troughs and pipelines. Given the low (non-existent) prevalence of JD in Qld and our climate and typical cattle grazing practices in the North Burnett, this is not an issue at present. It may become a problem, but not in the near future.
Not all Qld stud Brahman and Droughtmaster breeders export stud bulls to WA, so there will be breeders with high quality stud genetics not meeting the requirements for JD-BAS7, and producers who do meet the requirements for JD-BAS7 may, on occasion, wish to purchase stock from these breeders. Using AI or ET would eliminate this risk, but increases management inputs and costs. It is difficult/impossible at present to put numbers against the risk of importing JD in these situations, and the risk is expected to change with time, although how quickly and how much is impossible to even guess. It is accepted in the previous JD management scheme (Cattle MAP) that the status of a herd is not affected by up to 5% of the total herd being introduced from lower score herds. Quarantining these imported animals away from cattle under 18 months old for at least 2 years, while including introduced animals in yearly check tests for 4 years from date of introduction should almost eliminate the risk of spreading or maintaining JD in the herd. Ensuring young cattle under 18 months of age have no access to pastures, laneways and yards grazed by these ‘higher risk’ imports in the previous 12 months meets the ‘quarantine’ requirement (Contaminated/decontaminated land). If an imported animal was found to have JD, either by a check test or individual testing because of clinical symptoms of JD (and the reason for testing is important, see below), for practical purposes it should be possible to have a part of the property (a separate herd) still free of JD and able to export to WA.
Unfortunately, WA Department of Agriculture certainly would take a different view on this and claim that ANY diagnosis of JD on the property removes the property to a JD – BAS level 2 IF clinical signs of infection were present in the animal. The only way around this would be to run imported animals on a separate property/paddock, and treat the two properties as two separate entities (preferably with separate PIC), with double testing and all the associated extra costs. This would have to be in place BEFORE the diagnosis of JD was made, and all cattle movements from the quarantining property with the confirmed case to the exporting property would need to cease immediately.
To move from JD – BAS 2 to 7 requires removal of all infected animals, a Sample Test (ST) of all animals on the property over 2 years old 5 years after all infected animals have been removed, and three yearly Check Tests (CT, 50 animals over 2 years old). A diagnosis of JD with clinical symptoms on a property exporting to WA would eliminate the WA market for a MINIMUM of 5 years.
If an animal was diagnosed with JD on a JD – BAS 7 property and had NO clinical symptoms, the property only drops to JD – BAS 6, and can retest with a Sample Test (ST) two years later. If this Sample Test is negative, the herd regains its JD-BAS 7 status, providing the requirements for triennial check tests and the biosecurity plan have been maintained.
Unless producers exporting to WA are prepared to risk a 2 to 5 year minimum halt to trading, they should only allow animals from JD – BAS 7 properties to enter their property, or run two separate properties with separate PICs and biosecurity plans, both maintaining JD – BAS 7. One property would be the exporting property, and the other property would be the receiving property. Good testing of all imported animals to pick up infected animals early, on the receiving property, would allow animals to move between properties again within 2 years, while exports continue from the property which has remained a Score 7 during this time.
Producers will need to decide what level of risk they are prepared to run. At present, it would be reasonable to accept animals from any ‘Beef Only’ property in Queensland regardless of JD BAS (bearing in mind that all Qld properties were provisionally Score 7 until June 30, 2017 ). In the long term, the risks associated with this may increase. Purchasers may opt for an interim period where they will accept cattle from lower JD BAS properties, for example a 6. They may opt for the ‘two property’ approach, or go for the most security possible and only accept animals from Score 7 properties. One of the difficulties in determining the best course of action is the lack of knowledge applicable to the North Burnett regarding time to ‘decontaminate’ pastures. In other words, how long does it take from removing an animal shedding JD organisms in manure before young cattle (less than 18 months age) can safely graze that pasture? At present, we can only use the “worst case” official recommendation of 12 months. Common sense tells us that in the North Burnett environment it would certainly be less, but this is not proven and cannot be assumed.
The sheep strain of Johne’s Disease is of LITTLE or NO concern to cattle producers in the North Burnett. It should be noted that this template is NOT suitable to properties grazing sheep and cattle together, or with sheep in adjoining paddocks. Producers using this plan should avoid buying cattle from properties also running sheep, unless the property of origin is JD – BAS 7. In general, there are no commercial flocks of sheep in the North Burnett. There are three main reasons for this:
- Wild dog/dingo predation
- Intestinal worms in summer rainfall areas
- Black Speargrass (Heteropogon contortus) damage to carcases
Producers using this template must understand that they are responsible for the plan and level of risk they choose. While every effort has been made preparing this template, keeping information up to date, and then consulting with producers to finalise the plan for individual properties, the veterinarian can only advise, not guarantee. In fact, it is only possible to advise of the existence of these risks described above, not to quantify how large or small the risks actually are at any point in time. As compliance with the plan is beyond the veterinarian’s control or knowledge, and relies on the producer acting in good faith, any liability of the veterinarian in the event of JD entering a property using this biosecurity template, prepared and reviewed annually by that veterinarian, is denied. Using this template acknowledges this denial of liability.
The template takes form in sections:
- Introduction (which you are reading) setting out general principles of the disease and relationships between producers, veterinarians and WA in general.
- Main Biosecurity Plan, which should include:
- Contact details of relevant parties (Owners, Managers, Veterinarians and Stock Agents)
- List of reviews and changes made to the plan, by date.
- List of persons to be advised of changes to the plan
- Description, including sketch map, of the property, showing fences, laneways, feed and water points, areas (acres/Ha) of paddocks, yards,
- Contact details of owners and managers of adjoining properties with common fencing
- Description of the business operation, including stud/commercial numbers, routine health/management operations including vaccines, and a description of “flow” of cattle through the property (movements from paddock to paddock, and when these occur), including purchased cattle.
- A yearly planner of routine management operations, including the yearly review of the biosecurity plan (which comes under “Training” and “Auditing” in other templates).
- A supplementary section including a second copy of points 5, 6, 7 and 8 to be filled in and added as a temporary appendix describing short to medium term leased/agisted land.
- A list of ways biological matter can be introduced to the herd/property (risks), and a list of strategies the manager of the herd/property will use to mitigate these specific risks.
- Appendices dealing with specific Diseases/Pests
- Bovine Johnes Disease
- Others as added later.
- A “tick and flick” checklist used by the manager, and then the veterinarian, to evaluate the plan (and document the evaluation process).