Research Progress on Hair Cortisol as Evaluation Indicators of Chronic Stress

Making hair cortisol as the gold standard of reflecting chronic stress level is prospective and innovative.Hair cortisol not only can be used in detecting and estimating the chronic stress level of animals, but also can be benefit for understanding the body's physiological and pathological process and making effective health management strategy in time.Blood, saliva, urine and milk cortisol concentrations can be regarded as matrices for reflecting acute stress level as well, they have been used in detecting and establishing the diurnal profile of circulating cortisol studying.But hair which is a good supplementary matric can reflect the chronic stress level retrospectively.Hair cortisol as a reflection of the biochemical markers of chronic stress has the advantages of no invasive, relatively sensitive detection and convenient sampling stress, and hair cortisol is a heritable trait (h²=0.31).The utility of hair cortisol as a maker for HPA activity, and a useful tool for identifying genetic variation influences on long term individual differences in HPA activity.This article summarized the relationship between the cortisol and animal's healthy, the regulating mechanism and genetic adaptation change under chronic stress and the research progress of evaluation indicators during chronic stress, the research progress of hair as a matric of cortisol, the limitations and challenge of regarding hair cortisol as the biochemical marker to reflect the chronic stress level in the future.