Farm Sheep Johnes Disease Welfare

Johnes disease is a chronic wasting condition in sheep caused by bacterial infection that causes prolonged suffering and is difficult to detect and control.

Key Facts

Johnes disease is caused by Mycobacterium avium subspecies paratuberculosis
Sheep are infected as lambs but clinical signs appear at 2-5 years of age
The disease causes progressive weight loss, diarrhea, and bottle jaw from protein deficiency
No treatment is available and infected animals decline until death or slaughter
Diagnosis is difficult as the organism is shed intermittently and tests have low sensitivity
Herd control requires identification and culling of positive animals and biosecurity measures
The economic impact of Johnes disease on affected flocks can be severe

Welfare Considerations

Johnes disease causes prolonged suffering over months as infected animals progressively lose weight and condition despite adequate nutrition. The inability to absorb nutrients from the inflamed gut causes a form of starvation even in animals with food access. The gradual nature of the decline means animals may live in a deteriorating welfare state for an extended period before slaughter or death. Early identification and removal of positive animals prevents transmission to younger animals but does not help identified individuals. Prevention through purchasing from clean flocks and maintaining strict biosecurity is the most welfare-positive approach.

What You Can Do

Support flock health programs providing Johnes disease testing and biosecurity guidance
Purchase sheep only from flocks with negative Johnes disease status where possible
Advocate for testing requirements before movement of sheep between flocks
Choose lamb and wool from producers with documented Johnes disease management programs
Support research on improved diagnostic tests enabling earlier disease detection
Learn about Johnes disease transmission to understand biosecurity requirements in sheep management