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Your Environment. Your Health.

Comparative Medicine Branch

The NIH intramural research program has shifted all non-mission-critical laboratory operations to a maintenance phase in order to promote physical distancing and diminished transmission risk of COVID-19. Effective Monday, March 23, 2020, only mission-critical functions within NIH research laboratories will be supported.

The NIEHS Comparative Medicine Branch ensures the judicious and humane use of rodents for biomedical research that benefits human and animal health. We provide a broad range of services and collaborative support for the NIEHS intramural research program and National Toxicology Program. Highly trained professionals provide laboratory animal care, veterinary medical care, animal research project support, and genetically-engineered model development and preservation.

The NIEHS Comparative Medicine Branch maintains a rigorous Animal Care and Use Program, which has been fully accredited by the Association for Assessment and Accreditation of Laboratory Animal Care International since 1972. The program is led by a licensed veterinarian and technologists are certified by the American Association for Laboratory Animal Science.

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