Corticosterone in feathers is a long-term, integrated measure of avian stress physiology
1. Stress has pervasive consequences for the well-being of animals. Currently, understanding how individuals cope with stressors is typically accomplished via short-term quantification of blood glucocorticoids released after activation of the hypothalamic–pituitary–adrenal (HPA) axis. 2. We investigated whether the amount of corticosterone (CORT) deposited in growing feathers provides a long-term, integrated measure of HPA activity […]
Stress in free-ranging mammals: integrating physiology, ecology, and natural history
We review developments in the study of stress in free-ranging mammals and summarize the physiological and behavioral components of the stress response. Both the sympathetic nervous system response and the regulation and reactivity of the hypothalamic–pituitary–adrenal (HPA) axis are discussed. In particular, we describe how the activity of the HPA axis at baseline levels follows […]
Early Environmental Regulation of Glucocorticoid Feedback Sensitivity in Young Adult Monkeys
Variations in maternal care induce in neonatal rodents life-long changes in glucocorticoid feedback regulation of the hypothalamic-pituitary-adrenal axis. This aspect of plasticity in neuroendocrine development has not been established in primates. We assessed, in young adult squirrel monkeys, postnatal rearing effects on cortisol-induced suppression of corticotropin-releasing factor (CRF) stimulated secretion of adrenocorticotropic hormone (ACTH). Offspring […]
Early social isolation alters behavioral and physiological responses to an endotoxin challenge in piglets
Psychosocial stress in the form of maternal deprivation and social isolation during early postnatal life induces persistent alterations in behavioral and physiological mechanisms of adaptation. One consequence may be an increased susceptibility to diseases in later life. Therefore, the aim of the present study was to investigate in domestic piglets the effects of a repeated […]
Stress, captivity, and reproduction in a wild bird species
In seasonal species, glucocorticoid concentrations are often highest during the breeding season. However, the role of increased hypothalamic–pituitary–adrenal (HPA) activity in the regulation of reproduction remains poorly understood. Our study is the first, to our knowledge, to document reproductive consequences of a non-pharmacological hindrance to seasonal HPA fluctuations. Using wild-caught male and female European starlings […]
Maternal stress and plural breeding with communal care affect development of the endocrine stress response in a wild rodent
Maternal stress can significantly affect offspring fitness. In laboratory rodents, chronically stressed mothers provide poor maternal care, resulting in pups with hyperactive stress responses. These hyperactive stress responses are characterized by high glucocorticoid levels in response to stressors plus poor negative feedback, which can ultimately lead to decreased fitness. In degus (Octodon degus) and other […]
Does corticosterone regulate the onset of breeding in free-living birds?: The CORT-Flexibility Hypothesis and six potential mechanisms for priming corticosteroid function
For many avian species, the decision to initiate breeding is based on information from a variety of environmental cues, including photoperiod, temperature, food availability, and social interactions. There is evidence that the hormone corticosterone may be involved in delaying the onset of breeding in cases where supplemental cues, such as low food availability and inclement […]