Results 91 to 100 of about 3,636 (171)

Curse of the black spot: spotting negatively correlate with fitness in black grouse Lyrurus tetrix [PDF]

, 2016
There is growing evidence that achromatic plumage can act as honest indicators of male quality. In some species with areas of white plumage, black melanin spots can be found on parts of the feathers.
Badyaev, Bates, Bryant, Carl D. Soulsbury, Christophe Lebigre, Haase, Johnstone, Matti Kervinen, Mennill, Møller, Prum, Rintamäki, Stein, Stewart   +13 more
core   +1 more source

Head Color Morph‐ and Sex‐Specific Differences in Follistatin Gene Expression in the Gouldian Finch Brain

Journal of Comparative Neurology, Volume 533, Issue 10, October 2025.
Using highly sensitive and specific RNAscope in situ hybridization, we revealed that black‐headed morphs displayed higher follistatin (FST) mRNA levels across multiple brain regions associated with aggression, stress responses, and parental care compared to red‐headed morphs.
Changjiu Zhao, Farrah N. Madison
wiley   +1 more source

Parents and early life environment affect behavioral development of laying hen chickens. [PDF]

PLoS ONE, 2014
Severe feather pecking (SFP) in commercial laying hens is a maladaptive behavior which is associated with anxiety traits. Many experimental studies have shown that stress in the parents can affect anxiety in the offspring, but until now these effects ...
Elske N de Haas, J Elizabeth Bolhuis, Bas Kemp, Ton G G Groothuis, T Bas Rodenburg   +4 more
doaj   +1 more source

Assessing the effects of repeated handling on physiology and condition of semi-precocial nestlings [PDF]

, 2016
Repeated exposure to elevated levels of glucocorticoids during development can have long-term detrimental effects on survival and fitness, potentially associated with increased telomere attrition.
Davis P., Larsen W.A., R Core Team, Sapolsky R.M., Starck J.M., Zeichner S.L.   +5 more
core   +1 more source

Noninvasive assessment of corticosterone and triiodothyronine levels in the endangered Pyrenean Capercaillie (Tetrao urogallus aquitanicus)

Journal of Zoology, Volume 327, Issue 2, Page 183-195, October 2025.
Feathers are useful in the study of glucocorticoid and thyroid hormones in Pyrenean Capercaillies. Samples from the Northern Pyrenees and Pre‐Pyrenees contained lower corticosterone concentrations, and a negative correlation was found between corticosterone levels and the distance from cycling trails.
O. Nicolás de Francisco, A. Carbajal, O. Grau, I. Sacristán, A. C. Ewbank, A. Bellmunt, A. Moreno, I. Afonso Jordana, M. F. Martínez, J. Nadal, M. López‐Béjar, E. Ménoni, A. Margalida, C. Sacristán   +13 more
wiley   +1 more source

Corticosterone in feathers is a long‐term, integrated measure of avian stress physiology

Functional Ecology, 2008
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.
Bortolotti, Gary R., Marchant, Tracy A., Blas, Julio, German, T.   +3 more
openaire   +2 more sources

Effects of Forest Fragmentation on Feather Corticosterone Levels in an Amazonian Avian Community

Ardeola, 2020
Summary . In the Amazon, the construction of hydroelectric dams is an emergent driver of biodiversity loss, creating numerous land-bridge islands, most of them unable to sustain an assemblage of bird species comparable to the intact forest. Although we understand the effects of forest fragmentation on species richness and distribution, we still need to
Bicudo, Thiago, Anciães, Marina, Arregui, Lucia, Gil, Diego   +3 more
openaire   +3 more sources

Stocking Density Affects Stress and Anxious Behavior in the Laying Hen Chick During Rearing

Animals, 2019
The recent increases in stocking density, in extreme cases resulting in ‘crowding’, have a major impact on poultry welfare. In contrast to available research on adult laying hens, there is a gap in the literature studying the rearing phase ...
Kaya von Eugen, Rebecca E. Nordquist, Elly Zeinstra, Franz Josef van der Staay   +3 more
doaj   +1 more source

Sex-specific phenotypic integration: Endocrine profiles, coloration, and behavior in fledgling boobies [PDF]

, 2015
The intensity of color expression in animals plays a key role in social environments as a mechanism to signal individual capacities in competitive contests. Selective pressures for resource competition differ at different stages of life and between sexes;
Fargallo, Juan A., Gañán, Natalia, Lifshitz, Natalia, López-Rull, Isabel, Torres, Roxana, Velando, Alberto, Wakamatsu, Kazumasa   +6 more
core   +1 more source

Kortikosteron i fjær - en mulig velferdsindikator? [PDF]

, 2018
I dette prosjektet har vi utredet om kortikosteron målinger i fjær fra fjørfe kan være egnet som velferdsindikator.Vi har sammenligna tre besetninger: En liten økologisk eggproduksjonsbesetning og to slaktekyllingbesetninger med ordinære kyllinghus, syv ...
Johanssen, Juni Rosann E., Sørheim, Kristin   +1 more
core