The Tale of Stress: An Exploratory Analysis of Cortisol Levels in the Tail Hair of Captive Asian Elephants

January 2021 in “ PeerJ ”

Sanjeeta Sharma Pokharel, Hiroki Yoneda, Moe Yanagi, Raman Sukumar, Kodzue Kinoshita

cortisol stress biomarker physiological health

Studysummary This study observed that high levels of immunoreactive cortisol in the tail hair of captive Asian elephants were often associated with stressful or distinct behavioral events, suggesting its potential for reconstructing their physiological history.

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The study investigated cortisol levels in the tail-hair of six captive Asian elephants to assess stress. By analyzing hair samples and correlating cortisol levels with recorded stressful events, researchers found significant individual variations influenced by factors like age, sex, and environmental conditions. High cortisol levels were linked to stressors such as illness, social changes, and husbandry practices. The findings suggested that tail-hair cortisol could serve as a non-invasive biomarker for long-term stress monitoring, offering a retrospective calendar of an elephant's physiological health and providing valuable insights for improving their welfare in captivity.

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