From Big Medical Encyclopedia

HIBERNATION (synonym catalepsy) — the form of adaptation of animals to seasonal changes of living conditions consisting in temporary delay of vital processes. The page allows an animal to endure the adverse period, napr, considerable fall of temperature and a lack of fodder in the winter (winter S.), drying of reservoirs, the soil and plants used as food, in the summer (summer S.).

Preparation of an organism of an animal for S. consists in reorganization of many fiziol. and biochemical processes, to-rye are under influence and control of the neurohumoral system reflecting endogenous rhythmics and reacting to changes of living conditions (first of all on deterioration in opportunities of getting of food). Before S. in body tissues of an animal there is an accumulation of considerable reserves of fat, ascorbic to - you, a glycogen and vitamin E. During S. respiration intensity and blood circulations at mammals decreases by 10 — 20 times, a metabolism — by 20 — 40 times, and body temperature usually goes down to 5 — 1 °. Body weight during S. decreases by 30 — 40%. Deep S. is followed by falloff of body temperature to 0 ° below. At the same time ice in fabrics is not formed, and liquids are in the overcooled state; intensity of metabolic processes is very close to intensity of the metabolism which is able anabiosis (see).

In S., sometimes very deep and long, bats, many rodents (groundhogs, gophers, jerboas, etc.), insectivorous (hedgehogs, etc.), nek-ry predatory mammals (bears, badgers), and also nek-ry bird species fall (goatsuckers, martins, etc.).

Shifts fiziol. functions during S. are expressed at poikilothermic animals (see) in much bigger degree, than at gomoyotermny animals (see); at nek-ry mammals (e.g., at bears) body temperature practically does not change, animals are capable «to wake up», change a shelter etc.

Seasonal frequency of activity of many species of rodents, blood-sicking insects and mites is close to S. Therefore S. of many animal species serving by prokormitel of insects and mites, and also seasonal frequency of their activity define substantially a seasonal confinedness of distribution of many inf. and invasive diseases (plague, tularemia, arboviral infections, rickettsioses etc.), and also terms of holding the relevant preventive activities.

Studying fiziol. and the biochemical mechanisms which are the cornerstone of S. promoted development of methods of so-called artificial S. by deep cooling (see. Hibernation artificial ), and also methods of revival of the organism subjected to strong cooling.

Bibliography: Kalabukhov N. I. Hibernation of animals, Kharkiv, 1956; Naumov N. P. and Kartashev H. N. Zoologiya of vertebrata, p. 2, M., 1979; Slonim A. D. Fundamentals of the general ecological zoophysiology, M. — L., 1961.

V. F. Orlova.