Department of Physics, Chemistry and Biology (IFM)

Disruptions during early development can induce both short and long-term effects. Studies have shown that postnatal stress can affect an organism’s response to stress and induce anxiety and fear-related behaviors later on in life. Domestic White Leghorn chickens (Gallus gallus) that came from a commercial egg hatchery, where they were exposed to many potential stressors on their first day of life were compared to a control group, which were hatched at Linköping University and did not under go commercial hatchery procedures. When the chicks reached sexual maturity, various behaviors were measured and analyzed by a series of behavioral tests that included an emergence test, a social regrouping test and a novel object test to assess long-term behavioral effects. In the emergence test, no significant differences were found between hatchery stress (HS) and control birds although, females emerged significantly more than males (p = 0.02). In the social regrouping test, no treatment effects were found, but several behaviors were significantly affected by the social regrouping of the birds. Females were also generally more active than males. In the novel object test, no treatment effects were found, although males fed and foraged more than females (p = 0). These results indicate that exposure to stress on the first day of life has no long-term behavioral effects in domestic chickens.