It was shown that, depending on the ways of breeding and living conditions, realization of food-seeking and defensive behavioural reactions as well as single biochemical indexes (pattern of neurotransmitters and levels of free amino acids in the brain) in the wild type and hatchery-bred sturgeon juveniles differ significantly. Basing on the studied indexes, the juveniles, bred in the ponds, are close to the wild type juveniles, whereas the juveniles, bred by pool technique, are quite different from them.