TLDR Hair cortisol is a reliable stress indicator in cattle but may not be valid for pigs.
The study examined the effect of repeated ACTH administrations on hair cortisol concentrations (HCCs) in 34 cattle and 38 pigs to validate HCC as a stress indicator. In cattle, HCCs in natural, regrown, and segmented hair significantly increased after ACTH treatment, indicating heightened HPA axis activity and making HCC a promising stress indicator. In contrast, pigs showed no significant differences in HCCs between treated and control groups, likely due to a blunted cortisol response, seasonal hair growth, and contamination, suggesting HCC is less reliable for stress assessment in pigs under commercial conditions. The study emphasized the importance of considering external contamination and species-specific factors when using hair cortisol as a biomarker for stress.
296 citations
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October 2018 in “General and Comparative Endocrinology” Hair cortisol is a reliable way to measure long-term stress in animals.
118 citations
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October 2014 in “Journal of Dairy Science” Tail switch hair is best for measuring cortisol in Holstein cows, with white hair and multiparous cows showing higher levels.
501 citations
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October 2008 in “Psychoneuroendocrinology” Hair cortisol levels can show increased stress during late pregnancy but only for up to six months.
86 citations
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January 1996 in “Clinics in dermatology” Hair can be damaged by daily routines, but protein-based products can protect and improve it.
24 citations
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October 2018 in “Addiction Biology” Alcohol dependence affects stress hormone levels more than childhood maltreatment.
5 citations
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May 2021 in “Veterinary medicine and science” Injecting cosyntropin into grizzly bears increases blood cortisol but doesn't change hair cortisol levels.
May 2023 in “Animal Reproduction Update” High levels of cortisol in hair show long-term stress which can lower fertility in animals.
90 citations
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July 2014 in “Conservation Physiology” Hair cortisol levels in brown bears can be affected by both long-term and short-term stress.
16 citations
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January 2021 in “Frontiers in veterinary science” Pigs in farrowing crates and loose-housing systems showed no difference in chronic stress levels as measured by hair cortisol.
