- Rats, mice and other rodents: 90-95% · The remainder is mostly guinea pigs, hamsters, and rabbits.
- Pigs, sheep, nonhuman primates, cats, dogs, and other animals are needed far less often.
- Dogs and cats: less than 1%
- Non-human primates: less than 0.3%.
Mammals have been widely used, because of their obvious similarities in both structures and function to man. Rats, mice, guinea pigs, and hamsters came into favor because of their small size, short life span, ease of handling, high reproductive rate.
Mice in research:
- Along with rats and other rodents, mice make up the majority of animals used in medical research.
- Their small size and low cost makes them ideal for laboratory experiments. In addition, scientists can breed different strains of mice with natural genetic deficiencies to achieve specific models of human diseases.
- Cancer: Through breeding, researchers have developed mice with leukemia, breast cancer and many other types of cancer, allowing new treatments to be tested on animal models, instead of humans. Cells from human cancer tumors can be placed into immunologically deficient mice without rejection. This allows the study of human cancer without risking human lives. Studies with mice have shown that the immune system can be stimulated by genetically altered tumors, leading to hopes that gene therapy can be used to fight cancer.
- Immunology: Scientists are searching continuously for a best animal model for the study of AIDS. Much that we know about the devastating disease has come from research using mice, allowing scientists to apply information gained from mice to humans suffering from AIDS.
- Product safety: Mice, along with other rodents, are used in product safety tests, including measurements of the effects of long-term exposure of a product. Mice are also used to test a product’s safety on pregnant women and nursing babies.
- Research with mice helped develop vaccines to counter influenza, polio, yellow fever and rabies.
- Mice were also used in studies that show that the host, as well as the agent, plays a major role in viral infections.
Fertility treatments: The successful transfer of human embryos is possible today because of experiments in mice. This technique can also be used to improve reproduction in domestic and endangered species.