FIELD: biotechnology. SUBSTANCE: bacterial preparation is designed for preventing and treating animal and poultry diseases and as well for preparing gnotobiotic organisms. To isolate natural bacterial complexes, native biomaterial is selectively decontaminated by diluting it with liquid lactic bacterium-selective nutrient medium. This procedure allows removing accidentally occurring in biomaterial microorganisms foreign for given animal and poultry species. Subsequent treatment of diluted biomaterial with blood serum (or with immunoglobulin preparations) from the same animal or poultry family enables most complete removal of foreign microflora. Once fried of all contaminating microorganisms, biomaterial is cultured under anaerobic conditions. Resulting biomass is then reseeded, without isolating pure cultures into nutrient medium, and recultured under anaerobic conditions. EFFECT: more efficiently reduced mortality in chickens upon oral administration under industrial poultry keeping. 3 tbl, 4 ex
