Footrot is a bacterial disease of the feet of sheep. While the number of flocks with virulent (severe) strains of footrot has been reduced considerably over the last 20 years, footrot remains a serious disease with significant welfare and economic impacts.

Virulent footrot can be eradicated from flocks but at considerable expense and dependent on the season for success. Less virulent strains may not be eradicable but can cause considerable lameness and production loss. There is no simple way to assess the virulence of a given strain of footrot in the field, especially in the absence of optimal seasonal conditions, which creates problems for State-based control programs.

Better diagnosis and control of footrot should result in:

• Healthier, more productive sheep
• Easier trading between flocks
• Lower treatment and labour costs
• Increased confidence in State-based control programs.

AWI funded a project at the University of New England developed a DNA-based test to distinguish virulent and non-virulent strains. Specifically, the test discriminates between strains that are classed as ‘stable’ from the gelatin gel test but behave as either virulent or non-virulent in the field.

Other projects are currently under review.