The authors present a survey of the Soviet and foreign literature and findings of their own experimental studies. On the basis of these data the pathologo-anatomic picture of listerosis in laboratory animals (white mice, guinea-pigs and rabbits) is given in dynamics and histogenesis of focal changes in this disease in elucidated. The most typical feature of listerosis in animals is lesions of the kidney where focal changes in the form of granulems could be detected macroscopically at an early period and with great consistency. Several stages in its histogenesis may be discerned: I. focal necroses of hepatic cells associated with their invasion with lister Listeria; 2. appearance of cellular elements around the foci of necroses with subsequent formation of granulemas consisting mainly of leucocytes and lymphoid cells; 3. development of necrobiotic changes in the central areas of granulemas with concomitance of exudative processes; 4. organization of necrotic foci with subsequent scarring.