What happens to the majority of animals when the experiment in which they are being used has ended?
A majority of the animals used in experiments are euthanized (killed) during or after the experiment. (There are no accurate statistics available on exactly how many animals are euthanized in laboratories every year.) In some cases, animals are not euthanized, but die as a result of the research for which they were used. For example, the LD50 (lethal dose 50) test involves determining the dose of a substance that kills 50 percent of the animals tested. Some animals in laboratories, depending on the research protocol, can be used in additional experiments. It is extremely rare that animals are either adopted out or placed into a sanctuary after research is conducted on them. In 2000, however, a national sanctuary system was established for chimpanzees who were used in research. Click here for more information on the national sanctuary system and the CHIMP Act.
