Related Experiment Videos
Mycobacterium avium subsp. paratuberculosis: pathogen, pathogenesis and diagnosis
1School of Veterinary Medicine, University of Wisconsin, 2015 Linden Drive West, Madison, Wisconsin 53706, USA.
Summary
Johne's disease (paratuberculosis) is a chronic intestinal infection in ruminants caused by Mycobacterium avium subsp. paratuberculosis. This often fatal disease leads to significant economic losses and is challenging to manage due to its subclinical nature and ineffective treatments.
Area of Science:
- Veterinary Medicine
- Infectious Diseases
- Ruminant Health
Background:
- Johne's disease, also known as paratuberculosis, is a chronic intestinal infection caused by Mycobacterium avium subsp. paratuberculosis.
- It affects domestic and free-ranging ruminants, with potential impacts on other species, and is characterized by a long pre-clinical phase, cachexia, and sometimes diarrhea.
- The disease is often subclinical, leading to suspected under-reporting despite being notifiable in many countries.
Purpose of the Study:
- To provide an overview of Johne's disease (paratuberculosis) in ruminants.
- To highlight the prevalence, economic impact, and challenges associated with this infection.
- To underscore the risks to both domestic livestock and wildlife populations.
Main Methods:
- Literature review and synthesis of existing data on paratuberculosis prevalence and impact.
- Analysis of reported herd prevalence in different geographical regions (Europe, USA, Australia).
- Discussion of economic factors contributing to losses and challenges in disease management.
Main Results:
- Herd prevalence of bovine paratuberculosis in Europe varies widely (7%-55%).
- In the USA, prevalence is linked to herd size, with 40% of large herds infected.
- Australian dairy herds report infection rates between 9% and 22%.
Conclusions:
- Paratuberculosis causes substantial economic losses in domestic livestock through reduced production, culling, and veterinary expenses.
- The ineffectiveness and economic impracticality of treatment make disease control challenging.
- Both domestic livestock and wildlife populations (free-ranging and captive) are susceptible to paratuberculosis, necessitating ongoing surveillance and management strategies.