Abstract
The influence of embryonic microclimate on the behavioural development of birds remains unexplored. In this study, we experimentally tested whether chronic exposure to suboptimal temperatures engendered plasticity in the expression of fear-related behaviours and in the expression of the corticotropin-releasing factor in the brains of domestic chicks (Gallus g. domesticus). We compared the neurobehavioural phenotypes of a control group of chicks incubated in an optimal thermal environment (37.8 °C) with those of a group of experimental chicks exposed chronically in ovo to suboptimal temperatures (27.2 °C for 1 hour twice a day). Chronic exposure to a suboptimal temperature delayed hatching and decreased growth rate and experimental chicks had higher neophobic responses than controls in novel food and novel environment tests. In addition, experimental chicks showed higher expression of corticotropin-releasing factor than did controls in nuclei of the amygdala, a structure involved in the regulation of fear-related behaviours. In this study, we report the first evidence of the strong but underappreciated role of incubation microclimate on the development of birds’ behaviour and its neurobiological correlates.
Highlights
The influence of embryonic microclimate on the behavioural development of birds remains unexplored
We examined whether chronic exposure to a suboptimal temperature created conditions for the phenotypes of young birds to be shaped by the hypothetical parental environment
We evaluated the expression of the corticotropin-releasing factor in neonate brains in different nuclei of the arcopallium/amygdala, a brain region involved in fear-related behaviours
Summary
The influence of embryonic microclimate on the behavioural development of birds remains unexplored. We experimentally tested whether chronic exposure to suboptimal temperatures engendered plasticity in the expression of fear-related behaviours and in the expression of the corticotropin-releasing factor in the brains of domestic chicks Chronic exposure to a suboptimal temperature delayed hatching and decreased growth rate and experimental chicks had higher neophobic responses than controls in novel food and novel environment tests. Most studies considering the development of behaviour of avian species have focused on maternal effects mediated by egg quality, egg components, yolk hormones or post-hatching parental care[4]. Far less is known regarding the direct influence of embryos’ thermal environment This gap in our knowledge is surprising because avian embryos are poikilotherms, and their development relies entirely on parental incubation behaviour. We hypothesized that the temperature during incubation would influence the developmental plasticity of young birds’ behaviour
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
