Humane Endpoints for Guinea Pigs Used for Mycobacterium tuberculosis Vaccine Research

Area of Science:

• Veterinary Medicine
• Infectious Diseases
• Animal Models

Background:

• Guinea pigs are vital models for tuberculosis vaccine research.
• Current humane endpoints, primarily body weight loss, may not fully capture animal distress.
• Labored breathing was observed in tuberculosis-infected guinea pigs during chronic studies.

Purpose of the Study:

• To develop and validate consistent, refined humane endpoints for guinea pigs in tuberculosis research.
• To integrate multiple clinical signs for more accurate endpoint determination.
• To improve animal welfare by establishing precise euthanasia criteria.

Main Methods:

• An observational study was conducted using multiple clinical signs in tuberculosis-infected guinea pigs.
• Key indicators monitored included body weight loss, breathing effort, and activity levels.
• Histologic severity scores of lung lesions were used to support clinical endpoint assessments.

Main Results:

• A combination of body weight loss, labored breathing, and reduced activity reliably estimated the time to euthanasia within approximately 7 days.
• Histologic scores of lung lesions correlated with the established clinical endpoints.
• The refined endpoints provide a more comprehensive assessment of animal welfare.

Conclusions:

• The developed humane endpoints, integrating clinical signs and supported by histology, offer a more refined approach for tuberculosis vaccine studies.
• These endpoints enhance the consistency and accuracy of euthanasia decisions, improving animal welfare.
• This refinement is crucial for ethical considerations in preclinical tuberculosis research using guinea pigs.