IL2 and infection: The slight increase in the IL-2 concentration in the milk in the experimental and control groups between 24 and 72 h postpartum may have been due to infection of the mammary gland with bacteria from the animals’ living environment, but is not associated with inflammatory processes in the mammary gland, as clinical examination showed no pathological changes in the mammary gland of the sows (no changes in milk secretion, increase in the temperature of the tissues in the area, redness, swelling, or soreness).