HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) All Versions of this Article: 71/3/979    most recent biolreprod.104.029751v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Sockman, K. W. Articles by Ball, G. F. Search for Related Content PubMed PubMed Citation Articles by Sockman, K. W. Articles by Ball, G. F. Agricola Articles by Sockman, K. W. Articles by Ball, G. F.

Prior Experience with Photostimulation Enhances Photo-Induced Reproductive Development in Female European Starlings: A Possible Basis for the Age-Related Increase in Avian Reproductive Performance¹

Department of Psychological and Brain Sciences,³ Johns Hopkins University, Baltimore, Maryland 21218 Department of Biological Sciences,⁴ Simon Fraser University, Burnaby, British Columbia, Canada V5A 1S6 Centre for Ecology and Hydrology,⁵ Monks Wood, Abbots Ripton, Huntingdon, Cambridgeshire PE28 2LS, United Kingdom

Reproductive performance in female birds improves with age, and this is generally attributed to experiences obtained during breeding. In temperate-zone species, experience with photostimulation during the first breeding year may prime the hypothalamo-pituitary-gonadal axis to respond to photic cues more rapidly or robustly in subsequent years. To test this idea, we captured 32 photorefractory juvenile (hence naive to photostimulation) female European starlings (Sturnus vulgaris) and held half of them (naive group) on a photoperiod of 8L:16D for 32 wk and the other half (experienced group) on 8L:16D for 12 wk, 16L:8D for 12 wk, and then 8L:16D for 8 wk. When we subsequently transferred all birds to 16L:8D, the increase in body mass, which may presage egg laying in the wild, was more robust in experienced than in naive females. Experienced females also showed a more robust elevation in plasma concentrations of the yolk-precursor protein vitellogenin, although naive females showed an initial rapid but transient rise in vitellogenin that we attribute to their extended exposure to short-day photoperiods prior to photostimulation. Finally, the photo-induced increase in diameter of the largest ovarian follicle, in plasma concentrations of luteinizing hormone, and in the number of septo-preoptic fibers relative to the number of cell bodies immunoreactive to GnRH was greater in experienced than in naive females. Thus, prior experience with photostimulation enhances some initial phases of photo-induced reproductive development and may explain, in part, why reproductive performance improves with age in temperate-zone birds.

¹ Funding was provided by NIH/NICHD Individual NRSA 41854 to K.W.S. and NIH/NINDS R01 35467 to G.F.B.

² Correspondence and current address: Keith W. Sockman, Department of Biology, Coker Hall CB 3280, University of North Carolina, Chapel Hill, NC 27599. FAX: 919 962 1625; kwsockman{at}unc.edu

This article has been cited by other articles:

				L. Asher and M. Bateson Use and husbandry of captive European starlings (Sturnus vulgaris) in scientific research: a review of current practice Lab Anim, April 1, 2008; 42(2): 111 - 126. [Abstract] [Full Text] [PDF]