Over het archief
Het OWA, het open archief van het Waterbouwkundig Laboratorium heeft tot doel alle vrij toegankelijke onderzoeksresultaten van dit instituut in digitale vorm aan te bieden. Op die manier wil het de zichtbaarheid, verspreiding en gebruik van deze onderzoeksresultaten, alsook de wetenschappelijke communicatie maximaal bevorderen.
Dit archief wordt uitgebouwd en beheerd volgens de principes van de Open Access Movement, en het daaruit ontstane Open Archives Initiative.
Basisinformatie over ‘Open Access to scholarly information'.
one publication added to basket [257666] |
Yolk androgen deposition in rockhopper penguins, a species with reversed hatching asynchrony
Poisbleau, M.; Demongin, L.; Chastel, O.; Eens, M.; Quillfeldt, P. (2011). Yolk androgen deposition in rockhopper penguins, a species with reversed hatching asynchrony. Gen. Comp. Endocrinol. 170(3): 622-628. https://dx.doi.org/10.1016/j.ygcen.2010.11.027
In: General and Comparative Endocrinology. Elsevier: New York,. ISSN 0016-6480; e-ISSN 1095-6840, meer
| |
Trefwoord |
|
Author keywords |
Yolk testosterone (T); Yolk androstenedione (A4); Yolk 5alpha-dihydrotestosterone (DHT); Reversed hatching asynchrony; Layingsequence; Laying date |
Auteurs | | Top |
- Poisbleau, M., meer
- Demongin, L., meer
- Chastel, O.
|
- Eens, M., meer
- Quillfeldt, P.
|
|
Abstract |
To maximize fitness, females should invest optimally in the siblings within a litter or brood and adapt this investment to environmental conditions. Chick mass and yolk androgens have been shown to influence the outcome of sibling competition. In birds, asynchronous hatching plays a major role in this process and often leads to brood reduction. We studied maternal deposition of yolk androgens in eggs of southern rockhopper penguins (Eudyptes chrysocome chrysocome). Contrary to other avian models, laying and hatching sequences do not coincide in this species, which exhibits reversed hatching asynchrony. This provides a unique model to test whether the first egg to hatch (B-egg), which is the most likely to survive, differs in composition from the second egg to hatch (A-egg). We found that B-eggs had higher egg masses, yolk masses, yolk androgen concentrations and total yolk androgen amounts than A-eggs. This was observed consistently for the three androgens analyzed (testosterone, androstenedione and 5a-dihydrotestosterone). Laying date affected androgen deposition into A- and B-eggs differently. Interestingly, late clutches had proportionally higher androgen levels in the B-egg compared to the A-egg than early clutches. We discuss these results in relation to the chronology of egg formation and the potential effect of the observed differences on embryo development and brood reduction. |
IMIS is ontwikkeld en wordt gehost door het VLIZ.