Influence of External Factors on Hair Cortisol Concentrations

The study investigated the impact of external factors on hair cortisol concentrations in sheep, highlighting the potential for local cortisol production in the skin to affect these measurements. Eight sheep were subjected to various treatments, including extensive brushing and the application of a synthetic glucocorticoid, over three weeks. Results showed that hair cortisol concentrations significantly increased in areas treated with brushing or glucocorticoid, while no significant changes were observed with other treatments. The study concluded that caution should be exercised when using hair cortisol as a marker for chronic stress, as external factors can significantly influence the results.