, Volume 94, Issue 4, pp 319–325

Photoperiod affects daily torpor and tissue fatty acid composition in deer mice

  • Fritz Geiser
  • B. M. McAllan
  • G. J. Kenagy
  • Sara M. Hiebert
Short Communication

DOI: 10.1007/s00114-006-0193-z

Cite this article as:
Geiser, F., McAllan, B.M., Kenagy, G.J. et al. Naturwissenschaften (2007) 94: 319. doi:10.1007/s00114-006-0193-z


Photoperiod and dietary lipids both influence thermal physiology and the pattern of torpor of heterothermic mammals. The aim of the present study was to test the hypothesis that photoperiod-induced physiological changes are linked to differences in tissue fatty acid composition of deer mice, Peromyscus maniculatus (∼18-g body mass). Deer mice were acclimated for >8 weeks to one of three photoperiods (LD, light/dark): LD 8:16 (short photoperiod), LD 12:12 (equinox photoperiod), and LD 16:8 (long photoperiod). Deer mice under short and equinox photoperiods showed a greater occurrence of torpor than those under long photoperiods (71, 70, and 14%, respectively). The duration of torpor bouts was longest in deer mice under short photoperiod (9.3 ± 2.6 h), intermediate under equinox photoperiod (5.1 ± 0.3 h), and shortest under long photoperiod (3.7 ± 0.6 h). Physiological differences in torpor use were associated with significant alterations of fatty acid composition in ∼50% of the major fatty acids from leg muscle total lipids, whereas white adipose tissue fatty acid composition showed fewer changes. Our results provide the first evidence that physiological changes due to photoperiod exposure do result in changes in lipid composition in the muscle tissue of deer mice and suggest that these may play a role in survival of low body temperature and metabolic rate during torpor, thus, enhancing favourable energy balance over the course of the winter.


Torpor boutsFatHeterothermyThermal energeticsThermoregulation



monounsaturated fatty acids


polyunsaturated fatty acids


saturated fatty acids


air temperature


body temperature


unsaturated fatty acids

\({\mathop {\text{V}}\limits^{\text{.}} }{\text{O}}_{{\text{2}}} \)

rate of oxygen consumption


white adipose tissue

Copyright information

© Springer-Verlag 2006

Authors and Affiliations

  • Fritz Geiser
    • 1
  • B. M. McAllan
    • 1
    • 2
  • G. J. Kenagy
    • 3
  • Sara M. Hiebert
    • 1
    • 4
  1. 1.Centre for Behavioural and Physiological Ecology, ZoologyUniversity of New EnglandArmidaleAustralia
  2. 2.Discipline of Physiology, School of Medicine (F13)University of SydneySydneyAustralia
  3. 3.Burke Museum and Department of BiologyUniversity of WashingtonSeattleUSA
  4. 4.Department of BiologySwarthmore CollegeSwarthmoreUSA