After the II. World War central breedings of laboratory animals, mainly small laboratory rodents were established in Czechoslovakia. For the increasing needs of pharmaceutical industry there was as one of the first established the breeding facility of the Research Institute for Pharmacy and Biochemistry. Further development of scientific-research basis led in 1953 to establishing the breeding units of Czechoslovak Academy of Sciences (CSAV) and in 1956 to an independent enterprise of commercial character VELAZ, and in 1957 moreover is established the department of gnotobiology in the Institute of Microbiology CSAV. Laboratory animal breeding in Czechoslovakia underwent the same developmental characteristics as in the states with advanced scientific research and pharmaceutical industry, i.e. from the first demands for quantity of production to high quality of animals, definition and standardization. Which means from the conventional breeding to isolators and barrier units with a more effective laboratory control of animals and environmental factors. By establishing specialized breeding units in research institutes which ensured the demands of their own workplaces and developed research of the laboratory animals and fulfilling the demands from the part of VELAZ enterprise there was formed the production of usual species of laboratory animals.