Hibernation is a crucial strategy of winter survival used by many mammals. During hibernation, thirteen-lined ground squirrels, Ictidomys tridecemlineatus, cycle through a series of torpor bouts, each lasting more than a week, during which the animals are largely immobile. Previous hibernation studies have demonstrated that such natural models of skeletal muscle disuse cause limited or no chang...

Hibernation is a complex physiological response that some mammalian species employ to evade energetic demands. Previous work in mammalian hibernators suggests that hibernation is activated not by a set of genes unique to hibernators, but by differential expression of genes that are present in all mammals. This question of universal genetic mechanisms requires further investigation and can only ...

Polyunsaturated fatty acids (PUFAs) can have strong effects on hibernation and daily torpor in mammals. High dietary PUFA contents were found to increase proneness for torpor, decrease body temperatures, prolong torpor bout duration, and attenuate hibernation mass loss. The mechanism by which PUFAs enhance torpor and hibernation is unknown, however. On the basis of a review of the literature, a...

Ortmann, Sylvia, and Gerhard Heldmaier. Regulation of body temperature and energy requirements of hibernating Alpine marmots (Marmota marmota). Am. J. Physiol. Regulatory Integrative Comp. Physiol. 278: R698–R704, 2000.— Body temperature and metabolic rate were recorded continuously in two groups of marmots either exposed to seasonally decreasing ambient temperature (15 to 0°C) over the entire ...

Survival probability is predicted to underlie the evolution of life histories along a slow-fast continuum. Hibernation allows a diverse range of small mammals to exhibit seasonal dormancy, which might increase survival and consequently be associated with relatively slow life histories. We used phylogenetically informed GLS models to test for an effect of hibernation on seasonal and annual survi...

Torpor in hibernating mammals defines the nadir in mammalian metabolic demand and body temperature that accommodates seasonal periods of reduced energy availability. The mechanism of metabolic suppression during torpor onset is unknown, although the CNS is a key regulator of torpor. Seasonal hibernators, such as the arctic ground squirrel (AGS), display torpor only during the winter, hibernatio...

Garden Dormouse ( Eliomys quercinus ) populations have shown a drastic decline over the last 20-30 years, reasons for this are still unknown. In wild animals, body mass is good indicator of fitness and survival probability, especially in hibernating species like dormice. Fat accumulation before onset hibernation juvenile growth crucial to survive following winter. We conducted capture-mark-reca...