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Glucocorticoid response to food availability in breeding barn swallows (Hirundo rustica).

Authors :
Jenni-Eiermann S
Glaus E
Grüebler M
Schwabl H
Jenni L
Source :
General and comparative endocrinology [Gen Comp Endocrinol] 2008 Feb 01; Vol. 155 (3), pp. 558-65. Date of Electronic Publication: 2007 Aug 25.
Publication Year :
2008

Abstract

Parents feeding altricial nestlings have to trade-off the competing demands of self-maintenance and reproductive investment over their lifetime. Corticosterone, a glucocorticoid hormone released by birds in response to stressors, might play a key role in regulating parental investment when conditions unexpectedly deteriorate. However, birds breeding in unpredictable environmental conditions have been shown not to increase circulating levels of corticosterone as a response to bad weather to avoid nest abandonment when investment in offspring is high or when the probability of re-nesting is low. We investigated whether parent barn swallows Hirundo rustica, a passerine bird whose aerial insect food varies greatly in abundance depending on weather, also belongs to those species or whether it responds with an activation of the hypothalamo-pituitary-adrenal axis to natural variation in insect availability. We correlated plasma corticosterone levels of parents with weather conditions, the availability of aerial insects and parental body condition. Plasma corticosterone concentrations increased when mean daytime temperature declined, and consequently insect availability decreased and body condition of the parents deteriorated. Low temperatures also had a negative effect on body mass of the nestlings and there was a negative relationship between circulating corticosterone of parents and body mass of nestlings. We conclude that corticosterone is probably involved in the regulation of parental investment.

Details

Language :
English
ISSN :
0016-6480
Volume :
155
Issue :
3
Database :
MEDLINE
Journal :
General and comparative endocrinology
Publication Type :
Academic Journal
Accession number :
17904557
Full Text :
https://doi.org/10.1016/j.ygcen.2007.08.011