WoolProducers Australia (WPA) and Sheep Producers Australia (SPA) are seeking sheep and wool grower feedback on the future management of Ovine Johne’s Disease (OJD), with the 2013-2018 National Ovine Johne’s Disease Management Plan (NOJDMP) due to finish this year.
OJD is a wasting disease, caused by the sheep strain of the bacterium Mycobacterium paratuberculosis. Infection by the bacterium causes slow thickening of the intestinal wall, inhibiting the absorption of nutrients. Infected animals continue to eat and drink normally but lose condition, and can eventually waste away and die.
OJD is often not diagnosed until there is a distinct ‘tail’ in the mob where sheep can range in condition from good to very poor, before the ‘tail’ sheep start dying. For the first few years there is often no sign of the disease but infected sheep can be shedding the bacteria in their manure and contaminating the pasture and water supplies. Infection can spread to other sheep even though the flock still looks healthy.
The presence of OJD may only be noticed when there are large differences in adult sheep counts. Scouring may occur but is not common with Johne’s disease in sheep. Economic losses from OJD will result from sheep deaths, but also lost production of sheepmeat, lambs and wool and trading restrictions when the disease is not managed.
Once a flock is infected, eradication is difficult. There is no successful treatment or cure for infected sheep. The Gudair vaccine is a valuable tool that will significantly reduce the mortalities and shedding of OJD bacteria in infected flocks, but won’t entirely prevent OJD infection.
OJD is endemic in some high rainfall / sheep wheat production areas of Australia, but in others the disease hasn’t been detected or exists at a very low level. Due to very low to nil prevalence of OJD in NW Victoria, the North Western Victoria Regional Biosecurity Area was established to enable easier trading with South Australia.
The current NOJDMP will be reviewed to ensure OJD continues to be effectively managed and its spread is minimised. Review feedback will be used to determine if there is a need for a national OJD management framework in Australia, as well as refining current management strategies.
To seek feedback on the NOJDMP, and specifically the tools and elements that underpin the NOJDMP, a Discussion Paper – Future National Management of OJD has been developed.
To have your say about future management of OJD, complete the online producer survey available at: www.surveymonkey.com/r/ojdplan by 12 March 2018.
Further information is available via https://www.animalhealthaustralia.com.au/ojd-review/