Физиология и биохимия гидробионтов UDC 597.554.3-154.31 A. A. Filippov, V. V. Krylov, I. L. Golovanovа EFFECT OF MAGNETIC STORMS ON THE TEMPERATURE CHARACTERISTICS OF DIGESTIVE GLYCOSIDASES IN ROACH FINGERLINGS1 Abstract. <...> The aftereffects of a typical geomagnetic storm (the duration 24 h, in the frequency range 0–5 Hz) on the activity of glycosidase (maltase, amylolytic activity) in the intestine of a 4-month juvenile roach Rutilus rutilus (L.) have been studied. <...> Temperature characteristics of glycosidase in fish of the experimental and the control groups are similar. <...> Temperature optimum of amylolytic activity was observed at 40 ºC, the temperature optimum of maltase was found at 60 ºC. The Eact values of maltase at the temperature 0−30 °C are similar in both groups of yearlings. <...> The Eact values of amylolytic activity at feeding temperature 10−20 °C were significantly lower (the efficiency of the process is higher) than at lower temperatures in both groups of yearlings. <...> Introduction The geomagnetic storm (GMS) is a disturbance of the geomagnetic field, associated with an interaction of the perturbed flow of the solar wind and the Earth's magnetosphere. <...> The intensity of geomagnetic fluctuations during GMS does not often exceed 1 % of the intensity of the geomagnetic field. <...> Aftereffects of a real GMS reproduced in experimental conditions, on the early stages of roach development manifested as an increase in the mitotic activity in prelarvae cells [2], the decrease in size-weight characteristics and in vertebral phenotypes diversity in juveniles [3]. <...> Multidirectional changes in the activity of glycosidase (enzyme hydrolyzing carbohydrate) were previously found in the gut of juvenile roach subjected to the effect of lowfrequency magnetic field during its embryogenesis [4, 5]. <...> At the same time, there is no information about the aftereffect of the magnetic storm on the digestive function of fish. <...> The goal of the present work is to study the prolonged effects of GMS exposure during embryogenesis upon activities and temperature characteristics of intestinal glycosidase in roach fingerlings. <...> Materials and methods of research The fertilized eggs obtained from the parental roach Rutilus rutilus (L.) (8 females and 6 males) caught in May 2012 at the Rybinsk Reservoir spawning grounds were used for the experiments. <...> The geomagnetic storm (happened on 30–31 October 2003 and recorded at the latitude of the experiments) was reproduced in the experimental setup that allows compensating <...>