FIELD: agriculture, veterinary science. SUBSTANCE: invention proposes method of improvement of animals health that involves selection of at least one strain L. reuteri. The latter produces β-hydroxy-propionic aldehyde. Selected strain(s) in combination with antibiotic gentamycin are used for treatment of animal, for example, just now hatched poultry. EFFECT: increased growth gain, decreased lethality of poultry. 6 cl, 1 tbl, 1 ex
