Laboratory animals are animals on which a variety of medical, biological, veterinary, space, and other laboratory studies are conducted.
Research in some sections of medicine and biology is carried out on laboratory animals of certain species that have become "traditional." So, in experimental surgery dogs are used, in histology - cats, in physiology - dogs, rabbits, frogs and other animals, in virology - mice, monkeys, etc.
Laboratory animals must be healthy, have specific properties (susceptibility to test infections, sensitivity to test poisonous substances, etc.), and also have a small size, accessibility when handling them, low cost breeding and maintenance.
Special requirements are imposed on laboratory animals, which reveal the nature and causes of human hereditary diseases, malignant tumors, and experiments are carried out to overcome tissue incompatibility during organ and tissue transplants . For all these experiments, the need arose for breeding laboratory animals of pure lines (see). The number of known mouse lines now exceeds 400, the lines of rats are several dozen.
Lists of lines of all types of laboratory animals and sources of their receipt are published annually by the International Committee on Laboratory Animals for General Information. Contain laboratory animals in special rooms - vivariums (see).
For the experimental solution of individual problems of biology and medicine, in addition to vertebrates, various invertebrates are used. Most often these are protozoa - ciliates (eg, shoes), amoebas, flagellates, etc. Such insects as the fruit fly Drosophila are used to solve questions of variability, heredity, patterns of the mutation process, etc. In addition, laboratories widely use mosquitoes, mosquitoes , fleas , lice, flies; when studying the transfer of pathogens of human and animal diseases - Ixodes and argas mites; in the study of issues related to the prevention and treatment of helminth infections, roundworm, schistosomes and other helminths.