Why are there increasing numbers of mice and fish used in research?
It is important to note that more than 95% of all animals used in biomedical research are rodents. According to the U.S. Department of Agriculture (USDA), the number of research animals that are covered under the Animal Welfare Act (all animals except rats, mice and birds) have decreased by over 33% since 1973. This is largely because of scientists’ quest for alternatives to animal-based research. In some of the smaller species, such as mice and zebrafish, the numbers have increased due to the development of transgenic research. In this type of research, scientists are able to identify and produce specific breeding characteristics, enabling them to pinpoint and study a particular gene deficiency or trait.
