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Egg yolk androgen levels increase with breeding density in the European Starling, Sturnus vulgaris

Pilz, K M and Smith, Henrik LU (2004) In Functional Ecology 18(1). p.58-66
Abstract
1. High breeding density can cause elevated plasma androgen levels in adult birds. Since maternal androgens are deposited into egg yolk, high breeding density may result in elevated yolk androgen levels as well. 2. The relationship between breeding density and yolk androgen levels was examined in the European Starling, Sturnus vulgaris. The concentration and total content of yolk androstenedione and yolk testosterone were measured in eggs from 24 clutches distributed across nine different colonies of nestboxes. 3. Yolk androstenedione and testosterone levels were significantly higher in colonies where a greater proportion of nestboxes had active nests. 4. Yolk testosterone levels were significantly higher, and yolk androstenedione levels... (More)
1. High breeding density can cause elevated plasma androgen levels in adult birds. Since maternal androgens are deposited into egg yolk, high breeding density may result in elevated yolk androgen levels as well. 2. The relationship between breeding density and yolk androgen levels was examined in the European Starling, Sturnus vulgaris. The concentration and total content of yolk androstenedione and yolk testosterone were measured in eggs from 24 clutches distributed across nine different colonies of nestboxes. 3. Yolk androstenedione and testosterone levels were significantly higher in colonies where a greater proportion of nestboxes had active nests. 4. Yolk testosterone levels were significantly higher, and yolk androstenedione levels were marginally higher, in colonies with a greater absolute number of active nests. 5. Yolk androgen levels were not related to the number of active nests in adjacent nestboxes. 6. We conclude that female starlings nesting in colonies with higher breeding densities transfer more androgen to their eggs. 7. This relationship may be mediated by increased interfemale aggression, particularly towards floater females searching for mates or nests to brood parasitize, in high-density colonies. Such a relationship between maternal environment and maternal yolk androgens may represent adaptive maternal modification of offspring phenotype or a non-adaptive physiological constraint which females cannot avoid. (Less)
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author
organization
publishing date
type
Contribution to journal
publication status
published
subject
in
Functional Ecology
volume
18
issue
1
pages
58 - 66
publisher
Wiley-Blackwell
external identifiers
  • wos:000188821200007
  • scopus:1342311357
ISSN
1365-2435
DOI
10.1111/j.1365-2435.2004.00811.x
language
English
LU publication?
yes
id
f73b9956-6663-48bf-aec7-5863d8969f08 (old id 137086)
date added to LUP
2007-06-25 13:50:42
date last changed
2017-05-21 03:34:28
@article{f73b9956-6663-48bf-aec7-5863d8969f08,
  abstract     = {1. High breeding density can cause elevated plasma androgen levels in adult birds. Since maternal androgens are deposited into egg yolk, high breeding density may result in elevated yolk androgen levels as well. 2. The relationship between breeding density and yolk androgen levels was examined in the European Starling, Sturnus vulgaris. The concentration and total content of yolk androstenedione and yolk testosterone were measured in eggs from 24 clutches distributed across nine different colonies of nestboxes. 3. Yolk androstenedione and testosterone levels were significantly higher in colonies where a greater proportion of nestboxes had active nests. 4. Yolk testosterone levels were significantly higher, and yolk androstenedione levels were marginally higher, in colonies with a greater absolute number of active nests. 5. Yolk androgen levels were not related to the number of active nests in adjacent nestboxes. 6. We conclude that female starlings nesting in colonies with higher breeding densities transfer more androgen to their eggs. 7. This relationship may be mediated by increased interfemale aggression, particularly towards floater females searching for mates or nests to brood parasitize, in high-density colonies. Such a relationship between maternal environment and maternal yolk androgens may represent adaptive maternal modification of offspring phenotype or a non-adaptive physiological constraint which females cannot avoid.},
  author       = {Pilz, K M and Smith, Henrik},
  issn         = {1365-2435},
  language     = {eng},
  number       = {1},
  pages        = {58--66},
  publisher    = {Wiley-Blackwell},
  series       = {Functional Ecology},
  title        = {Egg yolk androgen levels increase with breeding density in the European Starling, Sturnus vulgaris},
  url          = {http://dx.doi.org/10.1111/j.1365-2435.2004.00811.x},
  volume       = {18},
  year         = {2004},
}