title: Is torpor only an advantage? Effect of thermal environment on torpor use in the Siberian hamsters (Phodopus sungorus).
abstract: The aim of our study was determine torpor use in the Siberian hamsters (Phodopus sungorus) tested in a wide gradient of ambient temperatures (T(a)). Experiments were done on fed and food-deprived animals acclimated to winter-like and summer-like conditions. We found that neither fed nor unfed hamsters acclimated to winter-like or summer-like conditions selected low T(a)'s and entered torpor. Instead, food deprivation led to selection of higher T(a)'s and slight lowering of body temperature (T(b)), especially during the rest-phase of the day. Our calculations show that this strategy may lead to higher energy savings than torpor would. We argue that torpor use is not a fixed strategy but is determined primarily by a thermal conditions available in the environment.
authors.affiliation: Department of Animal Physiology, Institute of General and Molecular Biology, Nicolaus Copernicus University, Toruń, Poland. mwoje@uni.torun.pl
authors.forename: M S
authors.initials: MS
authors.lastname: Wojciechowski
authors.forename: M
authors.initials: M
authors.lastname: Jefimow
mesh_terms: D000064:Acclimatization; D000222:Adaptation, Physiological / Q000502:physiology*; D000818:Animals; D001522:Behavior, Animal / Q000502:physiology*; D001833:Body Temperature Regulation / Q000502:physiology; D006224:Cricetinae; D004956:Estivation / Q000502:physiology; D005508:Food Deprivation; D006605:Hibernation / Q000502:physiology; D008297:Male; D017111:Phodopus; D017440:Photoperiod; D012621:Seasons; D013696:Temperature