Which animals make up about 95% of research animals?

Which animals make up about 95% of research animals?

• A. Mice & rats
• B. Dogs & cats
• C. Non-human primates
• D. Zebrafish

Answer: (A)

Most experimental animals come from mice and rats, which together account for about 95% of research animals. This large share comes from practical advantages: they are small, easy and inexpensive to house and breed, reach maturity quickly, and there are extensive genetic tools and well-established disease models for them. This combination makes them the go-to species for a wide range of studies and supports strong, comparable baseline data across many fields. Zebrafish are also widely used and valuable, especially for genetics and developmental work, but they do not reach the same overall scale as mice and rats. Dogs and cats, and particularly non-human primates, are used far less due to higher maintenance needs and stricter ethical and regulatory considerations.

Most experimental animals come from mice and rats, which together account for about 95% of research animals. This large share comes from practical advantages: they are small, easy and inexpensive to house and breed, reach maturity quickly, and there are extensive genetic tools and well-established disease models for them. This combination makes them the go-to species for a wide range of studies and supports strong, comparable baseline data across many fields. Zebrafish are also widely used and valuable, especially for genetics and developmental work, but they do not reach the same overall scale as mice and rats. Dogs and cats, and particularly non-human primates, are used far less due to higher maintenance needs and stricter ethical and regulatory considerations.