The main objective of the scientific and economic experiments was to determine the animal production feasibility and cost-effectiveness of early use of probiotic feed additives "Monosporin", "Prolam" and "Bacell". Introduction of beneficial microorganisms in the digestive tract of poultry at the earliest stages of life and in subsequent periods of growth has a positive effect on the survival rate and quality of the future laying hens, allowing grow replacement and fattened young chickens without the use of antibiotics with a higher body weight and lower unit cost. Tests have confirmed the economic feasibility of the complex application of probiotic feed additives "Monosporin", "Prolam" and "Bacell" during the growing period of the replacement and fattened young poultry, ranging from a very early stage even in the hatchery, and continuing to introduce "Bacell" in laying hens’ feed during the production period.