AGE-RELATED-CHANGES OF BEHAVIOR AND STATE OF THE CATECHOLAMINE SYSTEMIN THE EUROPEAN GRAYLING FRY

Age-related changes in behavior of the European grayling (Thymallus th ymallus L.) fry and the functional state of the catecholaminergic horm onal system have been studied in the laboratory from the moment of egg fertilization until the period of fry development. The pattern of age -related changes in behavioral reactions was preserved in different ye ars of observations. Several behavioral stereotypes have been identifi ed on the basis of analysis of these changes. Their successive alterna tion determines changes in migration of fish from the spawning grounds The results of biochemical testing are considered with respect to phy siological mechanisms of behavior.