Advanced

Reduced immune responsiveness contributes to winter energy conservation in an Arctic bird

Nord, Andreas LU ; Hegemann, Arne LU and Folkow, Lars P. (2020) In Journal of Experimental Biology 223(8).
Abstract
Animals in seasonal environments must prudently manage energy
expenditure to survive the winter. This may be achieved through
reductions in the allocation of energy for various purposes (e.g.
thermoregulation, locomotion, etc.). We studied whether such tradeoffs
also include suppression of the innate immune response, by
subjecting captive male Svalbard ptarmigan (Lagopus muta
hyperborea) to bacterial lipopolysaccharide (LPS) during exposure
to either mild temperature (0°C) or cold snaps (acute exposure to
−20°C), in constant winter darkness when birds were in energyconserving
mode, and in constant daylight in spring. The innate
immune response was mostly unaffected by temperature. However,
energy... (More)
Animals in seasonal environments must prudently manage energy
expenditure to survive the winter. This may be achieved through
reductions in the allocation of energy for various purposes (e.g.
thermoregulation, locomotion, etc.). We studied whether such tradeoffs
also include suppression of the innate immune response, by
subjecting captive male Svalbard ptarmigan (Lagopus muta
hyperborea) to bacterial lipopolysaccharide (LPS) during exposure
to either mild temperature (0°C) or cold snaps (acute exposure to
−20°C), in constant winter darkness when birds were in energyconserving
mode, and in constant daylight in spring. The innate
immune response was mostly unaffected by temperature. However,
energy expenditure was below baseline when birds were immune
challenged in winter, but significantly above baseline in spring. This
suggests that the energetic component of the innate immune
response was reduced in winter, possibly contributing to energy
conservation. Immunological parameters decreased (agglutination,
lysis, bacteriostatic capacity) or did not change (haptoglobin/PIT54)
after the challenge, and behavioural modifications (anorexia, mass
loss) were lengthy (9 days). While we did not study the mechanisms
explaining these weak, or slow, responses, it is tempting to speculate
they may reflect the consequences of having evolved in an
environment where pathogen transmission rate is presumably low
for most of the year. This is an important consideration if climate
change and increased exploitation of the Arctic would alter pathogen
communities at a pace outwith counter-adaption in wildlife. (Less)
Abstract (Swedish)
Animals in seasonal environments must prudently manage energy
expenditure to survive the winter. This may be achieved through
reductions in the allocation of energy for various purposes (e.g.
thermoregulation, locomotion, etc.). We studied whether such tradeoffs
also include suppression of the innate immune response, by
subjecting captive male Svalbard ptarmigan (Lagopus muta
hyperborea) to bacterial lipopolysaccharide (LPS) during exposure
to either mild temperature (0°C) or cold snaps (acute exposure to
−20°C), in constant winter darkness when birds were in energyconserving
mode, and in constant daylight in spring. The innate
immune response was mostly unaffected by temperature. However,
energy... (More)
Animals in seasonal environments must prudently manage energy
expenditure to survive the winter. This may be achieved through
reductions in the allocation of energy for various purposes (e.g.
thermoregulation, locomotion, etc.). We studied whether such tradeoffs
also include suppression of the innate immune response, by
subjecting captive male Svalbard ptarmigan (Lagopus muta
hyperborea) to bacterial lipopolysaccharide (LPS) during exposure
to either mild temperature (0°C) or cold snaps (acute exposure to
−20°C), in constant winter darkness when birds were in energyconserving
mode, and in constant daylight in spring. The innate
immune response was mostly unaffected by temperature. However,
energy expenditure was below baseline when birds were immune
challenged in winter, but significantly above baseline in spring. This
suggests that the energetic component of the innate immune
response was reduced in winter, possibly contributing to energy
conservation. Immunological parameters decreased (agglutination,
lysis, bacteriostatic capacity) or did not change (haptoglobin/PIT54)
after the challenge, and behavioural modifications (anorexia, mass
loss) were lengthy (9 days). While we did not study the mechanisms
explaining these weak, or slow, responses, it is tempting to speculate
they may reflect the consequences of having evolved in an
environment where pathogen transmission rate is presumably low
for most of the year. This is an important consideration if climate
change and increased exploitation of the Arctic would alter pathogen
communities at a pace outwith counter-adaption in wildlife. (Less)
Please use this url to cite or link to this publication:
author
; and
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
immune function, thermoregulation, bird, winter, season, Arctic, polar, bird, Arctic, polar, thermoregulation, immune response, anorexia, season, winter
in
Journal of Experimental Biology
volume
223
issue
8
article number
jeb219287
pages
11 pages
publisher
The Company of Biologists Ltd
external identifiers
  • pmid:32341183
  • scopus:85085255627
ISSN
1477-9145
DOI
10.1242/jeb.219287
language
English
LU publication?
yes
id
17e57296-9ef7-49c9-a268-0052bf2037e8
date added to LUP
2020-04-24 16:17:38
date last changed
2021-01-28 01:24:24
@article{17e57296-9ef7-49c9-a268-0052bf2037e8,
  abstract     = {Animals in seasonal environments must prudently manage energy<br/>expenditure to survive the winter. This may be achieved through<br/>reductions in the allocation of energy for various purposes (e.g.<br/>thermoregulation, locomotion, etc.). We studied whether such tradeoffs<br/>also include suppression of the innate immune response, by<br/>subjecting captive male Svalbard ptarmigan (Lagopus muta<br/>hyperborea) to bacterial lipopolysaccharide (LPS) during exposure<br/>to either mild temperature (0°C) or cold snaps (acute exposure to<br/>−20°C), in constant winter darkness when birds were in energyconserving<br/>mode, and in constant daylight in spring. The innate<br/>immune response was mostly unaffected by temperature. However,<br/>energy expenditure was below baseline when birds were immune<br/>challenged in winter, but significantly above baseline in spring. This<br/>suggests that the energetic component of the innate immune<br/>response was reduced in winter, possibly contributing to energy<br/>conservation. Immunological parameters decreased (agglutination,<br/>lysis, bacteriostatic capacity) or did not change (haptoglobin/PIT54)<br/>after the challenge, and behavioural modifications (anorexia, mass<br/>loss) were lengthy (9 days). While we did not study the mechanisms<br/>explaining these weak, or slow, responses, it is tempting to speculate<br/>they may reflect the consequences of having evolved in an<br/>environment where pathogen transmission rate is presumably low<br/>for most of the year. This is an important consideration if climate<br/>change and increased exploitation of the Arctic would alter pathogen<br/>communities at a pace outwith counter-adaption in wildlife.},
  author       = {Nord, Andreas and Hegemann, Arne and Folkow, Lars P.},
  issn         = {1477-9145},
  language     = {eng},
  number       = {8},
  publisher    = {The Company of Biologists Ltd},
  series       = {Journal of Experimental Biology},
  title        = {Reduced immune responsiveness contributes to winter energy conservation in an Arctic bird},
  url          = {http://dx.doi.org/10.1242/jeb.219287},
  doi          = {10.1242/jeb.219287},
  volume       = {223},
  year         = {2020},
}