Do cortisol and corticosterone play the same role incoping with stressors? Measuring glucocorticoid serum in free‐ranging guanacos (Lama guanaco).

OVEJERO R, NOVILLO A, SOTO‐GAMBOA M, MOSCA‐TORRES ME, CUELLO P,GREGÓRIO P, JAHN G, CARMANCHAHI P

JOURNAL OF EXPERIMENTAL ZOOLOGY PART A-ECOLOGICAL GENETICS AND PHYSIOLOGY

WILEY-LISS, DIV JOHN WILEY & SONS INC

Lugar: New York; Año: 2013 vol. 319 p. 539 - 547

1932-5223

Habitat can constrain and shape successful ecological and physiological strategies, thus providingthe context for the evolution of life‐history traits. However, unpredictable challenges, such asstorms, natural disasters, and human activities can also have great effects on stress. Glucocorticoids(GCs) are adrenal steroid hormones that play an important role in how vertebrates cope with thesepredictable and unpredictable environmental challenges. Although assessing GCs levels can havemany applications in the study of wildlife and/or captive animals, with or without capturingindividuals, it requires a species‐speci fic complete validation (analytical and biological) before itsuse. In this work, our aim was to: (a) validate a radioimmunoassay (RIA) for measuring GCs levels inL. guanicoe serum; (b) assess cortisol and corticosterone levels (if present) in serum of wildL. guanicoe individuals; and (c) compare the response to acute stressors (handling, shearing, andrelease). Our results successfully: (a) validated RIA for asses GCs levels in wild ungulates;(b) confirmed the presence for cortisol and corticosterone and showed that both GCs are differentlyaffected by environmental stimuli in L. guanicoe; and (c) showed that GCs exhibit differentpatterns in the field and in response to acute stressors, making these camelids an interestingendocrinological model when seeking the adaptive functions of a given variation and furtheremphasizing the complexity of GC physiology in wild mammals.