The study aims to identify genetic variants that influence ovine stress responsiveness. Increased stress induced glucocorticoid (cortisol) levels have been shown to negatively impact animal growth, production and health. Identifying specific genes that influence these stress responses in sheep could benefit the improvement of existing and alternative treatment and management strategies to support ovine health, welfare and production. This is particularly important in Australia where climate change (increased heat, drought, parasites etc) are already causing significant losses to the animal production industry, and there is a need to develop strategies to adapt to these changes.