[Participation of the fear reaction in limiting the period of primary socialization in silver foxes].

Administration of chloditan, an inhibitor of adrenal cortex function, at the terminal stage of the sensitive period of socialization of foxes reduced the cortisol concentration in blood as compared with control and intact animals aged 45 and 60 days. Simultaneously, the weakening of fear reaction and an enhancement of exploratory and motor activities in an unknown surrounding were observed. However, administration of chloditan did not affect the duration of the sensitive period of socialization, since the aggressive defensive reactions changed neither at the age of 45 and 60 days, nor at the age of 7 months.