EN
In this short review the presence, relative concentrations of the plasma, and a possible physiological role of hormones in the cow’s milk have been discussed. On the basis of available data, three categories of hormones in milk have been differentiated: 1 — hormones which exist in trace amounts originated from circulation, 2 — hormones which occur in milk during some phases of lactation in higher concentrations than those in the blood, 3 — hormones synthesized by the mammary gland. The possible biological significance of the hormones for the mammary gland, for the mother and offspring has been emphasized.