Biomaterial Database

Metabolism, thermogenesis and daily rhythm of body temperature in the wood lemming, Myopus schisticolor. 1993

S Saarela, and R Hissa

University of Oulu, Department of Zoology, Finland.

Wood lemmings (Myopus schisticolor) were captured during their autumnal migration in September and October. The animals were maintained at 12 degrees C and under 12L:12D photoperiod. Basal metabolic rate and thermogenic capacity of the wood lemming were studied. Basal metabolic rate was 3.54 ml O2.g-1.h-1, which is 215-238% of the expected value. The high basal metabolic rate seems to be typical of rodents living in high latitudes. The body temperature of the wood lemming was high (38.0-38.8 degrees C), and did not fluctuate much during the 24-h recording. The high basal metabolic rate and the high body temperature are discussed with regard to behavioural adaptation to a low-quality winter diet. Thermogenic capacity, thermal insulation and non-shivering thermogenesis of the wood lemming displayed higher values than expected: 53.0 mW.g-1, 0.53 mW.g-1.degrees C-1 and 53.2 mW.g-1, respectively. Brown adipose tissue showed typical thermogenic properties, although its respiratory property was fairly low, but mitochondrial protein content was high compared to other small mammals. The 24-h recording of body temperature and motor activity did not reveal whether the wood lemming is a nocturnal animal. Possibly, the expression of a circadian rhythm was masked by peculiar feeding behaviour. It is concluded that the wood lemming is well adapted to living in cold-temperature climates.

UI	MeSH Term	Description	Entries
D009043	Motor Activity	Body movements of a human or an animal as a behavioral phenomenon.	Activities, Motor,Activity, Motor,Motor Activities
D001833	Body Temperature Regulation	The processes of heating and cooling that an organism uses to control its temperature.	Heat Loss,Thermoregulation,Regulation, Body Temperature,Temperature Regulation, Body,Body Temperature Regulations,Heat Losses,Loss, Heat,Losses, Heat,Regulations, Body Temperature,Temperature Regulations, Body,Thermoregulations
D002001	Adipose Tissue, Brown	A thermogenic form of adipose tissue composed of BROWN ADIPOCYTES. It is found in newborns of many species including humans, and in hibernating mammals. Brown fat is richly vascularized, innervated, and densely packed with MITOCHONDRIA which can generate heat directly from the stored lipids.	Brown Fat,Hibernating Gland,Brown Adipose Tissue,Fat, Brown,Tissue, Brown Adipose
D002940	Circadian Rhythm	The regular recurrence, in cycles of about 24 hours, of biological processes or activities, such as sensitivity to drugs or environmental and physiological stimuli.	Diurnal Rhythm,Nyctohemeral Rhythm,Twenty-Four Hour Rhythm,Nycthemeral Rhythm,Circadian Rhythms,Diurnal Rhythms,Nycthemeral Rhythms,Nyctohemeral Rhythms,Rhythm, Circadian,Rhythm, Diurnal,Rhythm, Nycthemeral,Rhythm, Nyctohemeral,Rhythm, Twenty-Four Hour,Rhythms, Circadian,Rhythms, Diurnal,Rhythms, Nycthemeral,Rhythms, Nyctohemeral,Rhythms, Twenty-Four Hour,Twenty Four Hour Rhythm,Twenty-Four Hour Rhythms
D003081	Cold Climate	A climate characterized by COLD TEMPERATURE for a majority of the time during the year.	Polar Regions,Climate, Cold,Climates, Cold,Cold Climates,Polar Region,Region, Polar,Regions, Polar
D003411	Arvicolinae	A subfamily of MURIDAE found nearly world-wide and consisting of about 20 genera. Voles, lemmings, and muskrats are members.	Clethrionomys,Cricetidae,Dicrostonyx,Lemmings,Lemmus,Mice, Red-Backed,Microtinae,Microtus,Muskrats,Ondatra,Voles,Arvicolines,Microtines,Mouse, Red-Backed,Myodes,Ondatra zibethicus,Arvicoline,Lemming,Mice, Red Backed,Microtine,Mouse, Red Backed,Muskrat,Red-Backed Mice,Red-Backed Mouse,Vole
D000064	Acclimatization	Adaptation to a new environment or to a change in the old.	Acclimation
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D001481	Basal Metabolism	Metabolism (e.g., heat production) of an organism in an inactive, awake, fasting state. It may be determined directly by means of a calorimeter or indirectly by calculating the end products of oxidation within the organism or from the amount of oxygen utilized.	Metabolism, Basal,Basal Metabolic Rate,Metabolic Rate, Basal,Resting Metabolic Rate,Basal Metabolic Rates,Metabolic Rate, Resting,Rate, Basal Metabolic,Rate, Resting Metabolic,Resting Metabolic Rates
D012377	Rodentia	A mammalian order which consists of 29 families and many genera.	Beavers,Capybaras,Castor Beaver,Dipodidae,Hydrochaeris,Jerboas,Rodents,Beaver,Capybara,Hydrochaeri,Jerboa,Rodent,Rodentias