Effects of Small Increases in Corticosterone Levels on Morphology, Immune Function, and Feather Development

Authors

Michael W. Butler, Boise State University
Lynda L. Leppert, Alaska Sea Life Center
Alfred M. Dufty Jr., Boise State UniversityFollow

Document Type

Article

Publication Date

1-15-2010

DOI

http://dx.doi.org/10.1086/648483

Abstract

Stressors encountered during avian development may affect an individual’s phenotype, including immunocompetence, growth, and feather quality. We examined effects of simulated chronic low-level stress on American kestrel (Falco sparverius) nestlings. Continuous release of corticosterone, a hormone involved in the stress response, can model chronic stress in birds. We implanted 13-d-old males with either corticosterone-filled implants or shams and measured their growth, immune function, and feather coloration.We found no significant differences between groups at the end of the weeklong exposure period in morphometrics (mass, tarsus, wing length, and asymmetry), immunocompetence (cutaneous immunity, heterophil/lymphocyte ratio, and humoral immunity), or feather coloration. One week subsequent to implant removal, however, differences were detected. Sham-implanted birds had significantly longer wings and a reduced level of cutaneous immune function compared with those of birds given corticosterone-filled implants. Therefore, increases of only 2 ng/mL in basal corticosterone titer can have small but measurable effects on subsequent avian development.

Copyright Statement

This document was originally published by University of Chicago Press in Physiological and Biochemical Zoology. Copyright restrictions may apply. DOI: 10.1086/648483

Publication Information

Butler, Michael W.; Leppert, Lynda L.; and Dufty, Alfred M. Jr.. (2010). "Effects of Small Increases in Corticosterone Levels on Morphology, Immune Function, and Feather Development". Physiological and Biochemical Zoology, 83(1), 78-86.