Farmed Cattle Johnes Disease Welfare and Biosecurity

Johnes disease is a chronic, progressive wasting disease affecting cattle and other ruminants. Its prolonged course causes sustained suffering and is preventable through biosecurity and testing.

Key Facts

Johnes disease (paratuberculosis) is caused by Mycobacterium avium subspecies paratuberculosis (MAP)
Cattle are typically infected as calves but clinical signs may not appear for 2-10 years
Clinical disease causes progressive protein-losing enteropathy, weight loss, bottle jaw, and death
No effective treatment exists — affected cattle are typically culled when clinical signs appear
Johnes disease is estimated to cost the US cattle industry over $200 million annually
Vaccination reduces disease severity but does not prevent infection completely

Welfare Considerations

Johnes disease causes prolonged suffering in affected cattle — the protein loss and malnutrition of advanced disease lead to visible emaciation, chronic diarrhea, and progressive weakness over weeks to months before death or culling. Because the disease has a long subclinical period, cattle may be spreading infection for years before showing signs. The welfare cost is thus distributed across both individual suffering in clinical animals and the production-system harm of endemic infection. Prevention through biosecurity measures and calves exposure management is the primary welfare intervention, as treatment cannot restore health once clinical disease develops.

What You Can Do

Support cattle operations with active Johnes disease testing and control programs
Advocate for welfare standards that include regular MAP testing in dairy and beef herds
Choose dairy products from farms with documented Johnes disease control programs where available
Support research into effective Johnes disease vaccines and early diagnostic tools
Reduce dairy and beef consumption to decrease demand from operations with poor disease management