Dealing with Johnne's disease
BIOSECURITY agencies are reminding all beef and dairy cattle producers that a new national bovine Johne’s disease (BJD) strategic plan is now in effect, following a comprehensive review of the national approach to managing and preventing BJD.
The new plan is based on risk management of Johne’s disease and divides Australia into four BJD areas and zones:
•Western Australia will continue as a Free Zone
•Queensland, Northern Territory and the northern pastoral area of South Australia will remain Protected Zones
•New South Wales and the southern agricultural area of South Australia will become Beef Protected Areas (BPAs)
•Victoria and Tasmania will be classified as Management Areas.
The main changes will affect NSW and SA, in which the current Control and Protected Zones will be replaced by the BPA.
Within the BPA there will be a separate dairy compartment, which is defined as farms that supply milk to a dairy factory, and includes any land the dairy cattle have run on.
Biosecurity Queensland principal veterinary officer Dr Lawrence Gavey said although Queensland was fortunate to maintain its Protected Zone status, it was essential that all cattle owners - and others wanting to introduce cattle from other states - were aware of the new strict entry requirements for each state and zone or area.
“With the introduction of the new zones/areas, cattle producers should familiarise themselves with the requirements for introducing both beef and dairy cattle into other states,” he said.
“Producers need to protect their herd, by educating themselves on the disease, knowing the entry requirements and making detailed enquiries regarding the herd history before introducing new animals to their herd.
“BJD can have a serious welfare and financial impact if it is not controlled, as it affects production and market access, seriously disrupting farm businesses.
“Johne’s disease is one of those situations where an ounce of prevention is worth a tonne of cure.”
BJD is a serious wasting disease of cattle which can lead to loss of production and death and is seen more often in dairy herds than beef herds. BJD is also an infectious disease of goats, deer and alpacas.
Dr Gavey said the disease affected animals by causing thickening of the intestinal wall resulting in a reduction in the normal absorption of food.
“The disease is caused by a bacterium (Mycobacterium avium paratuberculosis) that lives mainly in animal intestines, but can also survive in the outside environment for several months,” he said.
“The bacteria causing BJD can be brought onto a property by purchasing infected animals, agisting infected stock of unknown status or from straying animals.
“Cattle acquire infection at an early age through eating contaminated pasture or drinking contaminated milk or water.”