Laboratory Animals

animals used in laboratory experiments for scientific and practical purposes.

Laboratory animals must, first of all, be healthy. In addition, they must possess certain special features (for example, susceptibility to the infections or sensitivity to the substances being investigated) and be inexpensive to breed and keep. In experiments, the species characteristics are taken into account (for example, rodents are nocturnal). Purebred and sterile animals (those free of bacteria, fungi, protozoans, viruses) are used with growing frequency. White mice and rats are used most often for research in genetics, microbiology, virology, toxicology, and radiobiology. Dogs, cats, rabbits, monkeys, frogs, hamsters, cotton rats, voles, gerbils, Siberian polecats, muishonds, and moles are used for physiological studies. Experiments are also often performed on turtles, fish, birds, many invertebrates (for example, worms; insects, such as Drosophila; and ticks), and protozoans. The laboratory animals are kept in vivaria or insectaries. The experimental use of embryos (for example, of birds), tissue cultures, and isolated organs is increasing.