To produce chicks from hatching eggs, the eggs are incubated in a hatcher incubator. After hatching, chicks of lesser quality are screened out, and the remaining chicks are transferred to a poultry barn. During the first week in the barn, a number of chicks are lost. When the loss rate exceeds a certain value, treatment with antibiotics is usually applied. Methods and compositions for reducing the loss rate during the first week and thus the number of antibiotic treatments are disclosed. The methods include providing in the air of the hatcher incubator at least during a final stage of the incubation and hatching of the eggs in the hatcher incubator, an active amount of a pheromone composition with the appeasing effect of the mother hen pheromone. The pheromone composition can be applied in the hatcher incubator at a specific height in the form of a formulation.
