[Corticosteroid concentration in the blood of the Russian sturgeon, Acipenser güldenstädti, at different stages in its life cycle].

Corticosteroid content of the blood has been measured during upstream and downstream migrations as well as during sea period of life of the sturgeon A. galdenstädti. It was shown that during anadromous migration before spawing, the level of corticosteroids in the blood increases, the increases beginning already during the sea period.