Limits to sustained energy intake. XXIII. Does heat dissipation capacity limit the energy budget of lactating bank voles?

Edyta T. Sadowska, Elzbieta Krol, Katarzyna M. Chrzascik, Agata M. Rudolf, John R. Speakman, Paweł Koteja

Research output: Contribution to journalArticlepeer-review

24 Citations (Scopus)
7 Downloads (Pure)

Abstract

Understanding factors limiting sustained metabolic rate (SusMR) is a central issue in ecological physiology. According to the heat dissipation limit (HDL) theory, the SusMR at peak lactation is constrained by the maternal capacity to dissipate body heat. To test that theory, we shaved lactating bank voles (Myodes glareolus) to experimentally elevate their capacity for heat dissipation. The voles were sampled from lines selected for high aerobic exercise metabolism (A; characterized also by increased basal metabolic rate) and unselected control lines (C). Fur removal significantly increased the peak-lactation food intake (mass-adjusted least square means±s.e.; shaved: 16.3±0.3 g day(-1), unshaved: 14.4±0.2 g day(-1); P<0.0001), average daily metabolic rate (shaved: 109±2 kJ day(-1), unshaved: 97±2 kJ day(-1); P<0.0001) and metabolisable energy intake (shaved: 215±4 kJ day(-1), unshaved: 185±4 kJ day(-1); P<0.0001), as well as the milk energy output (shaved: 104±4 kJ day(-1); unshaved: 93±4 kJ day(-1); P=0.021) and litter growth rate (shaved: 9.4±0.7 g 4 days(-1), unshaved: 7.7±0.7 g 4 days(-1); P=0.028). Thus, fur removal increased both the total energy budget and reproductive output at the most demanding period of lactation, which supports the HDL theory. However, digestive efficiency was lower in shaved voles (76.0±0.3%) than in unshaved ones (78.5±0.2%; P<0.0001), which may indicate that a limit imposed by the capacity of the alimentary system was also approached. Shaving similarly affected the metabolic and reproductive traits in voles from the A and C lines. Thus, the experimental evolution model did not reveal a difference in the limiting mechanism between animals with inherently different metabolic rates.

Original languageEnglish
Pages (from-to)805-815
Number of pages11
JournalJournal of Experimental Biology
Volume219
Issue number6
Early online date8 Jan 2016
DOIs
Publication statusPublished - 16 Mar 2016

Bibliographical note

Acknowledgements
We are grateful to our technicians and several students for their help during this
study and for animal care. We thank Catherine Hambly and Peter Thompson for
technical assistance for the isotope analysis for the DLW measurements. We thank
Ulf Bauchinger for stimulating discussion and his comments, and two anonymous
referees for comments on the manuscript.

Funding
This project was supported by grants from the Polish Ministry of Science and Higher
Education [0595/B/P01/2011/40 to E.T.S. and 8167/B/P01/2011/40 to P.K.], and
Jagiellonian University [DS/WBINOZ/INOS/757 to P.K.].

Keywords

  • artificial selection
  • doubly labelled water
  • food consumption
  • maternal investment
  • milk energy output
  • thermal conductance

Fingerprint

Dive into the research topics of 'Limits to sustained energy intake. XXIII. Does heat dissipation capacity limit the energy budget of lactating bank voles?'. Together they form a unique fingerprint.

Cite this