Proceedings of the 10th International Colloquium on Paratuberculosis

#126
The National Sheep Health Statement - a tool for assessing Johne’s disease
risk in <strong>the</strong> sheep industries
Rodney Watt 1 , David Kennedy 2, Lorna Citer 3
1. Sheepmeat Council <strong>of</strong> Australia. 2. Technical Adviser National Johne’s Disease Control
Program Animal Health Australia 3. Manager Endemic Disease, Animal Health Australia
ABSTRACT
Ovine Johne's disease (OJD) has spread widely in Australia since its detection in 1980 and is
now established in higher rainfall areas in south-eastern and south-western Australia.
Initially <strong>the</strong> national program was based on traditional tools <strong>of</strong> zoning, quarantine and
attempted eradication from individual farms, and was complemented by <strong>the</strong> Market
Assurance Program to promote low risk flocks. However, without financial support for <strong>the</strong>
owners <strong>of</strong> infected flocks, producers actively sought to avoid detection <strong>of</strong> <strong>the</strong> disease.
A mid-term review <strong>of</strong> <strong>the</strong> program provided <strong>the</strong> impetus to evaluate <strong>the</strong> risk factors in
<strong>the</strong> spread <strong>of</strong> <strong>the</strong> disease and to undertake a quantitative risk assessment that could be form
<strong>the</strong> basis <strong>of</strong> an assurance declaration form. This was developed into <strong>the</strong> Assurance Based
Credit (ABC) Scheme which has been incorporated into <strong>the</strong> National Sheep Health
Statement (SHS) to encourage prospective purchasers to obtain <strong>the</strong> NHS before purchasing
sheep. The declaration provides producers with <strong>the</strong> ability to assess <strong>the</strong> risk associated with
<strong>the</strong> flock <strong>of</strong> origin and activities undertaken to reduce <strong>the</strong> risk. The SHS also includes
declarations for o<strong>the</strong>r important production diseases <strong>of</strong> sheep.
The current national program was developed and implemented through a partnership
between industry and governments and is largely funded by <strong>the</strong> national sheep industries. It
provides trading opportunities for both infected and not assessed flocks using a risk based
trading system underpinned by surveillance information, a readily available vaccine and a
uniform vendor declaration which is supported by government regulation.
BACKGROUND
Ovine Johne's disease has spread widely since its detection in central New South Wales in
1980 and is now established in higher rainfall production systems in south-eastern and
south-western Australia. Sheep are regularly traded across state borders in Australia and,
depending on local pastoral conditions, may move several hundred kilometres. This has <strong>the</strong>
potential to seed disease to areas not previously infected with OJD.
Initially <strong>the</strong> national program was based on traditional tools <strong>of</strong> zoning, quarantine and
attempted eradication from individual farms, and was complemented by <strong>the</strong> Market
Assurance Program to promote low risk flocks. State authorities regulated <strong>the</strong> program
which led to different requirements for disease control and certification between states, and
an increasing reliance on state borders to control disease.
Producers were required to complete a state based OJD declaration form each time
sheep moved or were traded, which fur<strong>the</strong>r impacted <strong>the</strong> sheep trade. Producers were also
required to complete additional documentation for movement requirements and for o<strong>the</strong>r
disease conditions.
Since 2004 <strong>the</strong>re has been a progressive de-regulation <strong>of</strong> OJD and <strong>the</strong> adoption <strong>of</strong> an
industry initiated program that has been developed with <strong>the</strong> support <strong>of</strong> state animal health
authorities. This change <strong>of</strong> direction in national policy is consistent with similar approaches
developed for <strong>the</strong> management <strong>of</strong> bovine Johne's disease by o<strong>the</strong>r livestock industries.
The National Sheep Health Statement was developed by national industry groups,
livestock agents and state governments to provide a standard for <strong>the</strong> voluntary declaration <strong>of</strong>
sheep health risk across Australia. Prospective buyers <strong>of</strong> sheep are able to assess <strong>the</strong> risk a
line <strong>of</strong> sheep represents to <strong>the</strong>ir own flock and in some states, is used for declaration <strong>of</strong>
interstate movements.
218