The aim of this Master’s project was to assess the acute effects of hatchery stress on day old commercial laying chickens through blood corticosterone analysis and behavioural tests up to one week of age. A secondary aim of this project was to assess whether the impacts of hatchery stress continue to negatively impact chickens throughout developmental stages such as puberty and sexual maturation. Another aim of this project was to compare the impact of hatchery routines on male and female white leghorn commercial chickens.