Skin temperature reveals the intensity of acute stress.
Bottom Line: We used established behavioural and hormonal markers: activity level and corticosterone level, to validate a mild and more severe form of an acute restraint stressor in hens (Gallus gallus domesticus).In the comb and wattle, two skin regions with a known thermoregulatory role, stressor intensity predicted the extent of initial skin cooling, and also the occurrence of a more delayed skin warming, providing two opportunities to quantify stress.With the present, cost-effective availability of IRT technology, this non-invasive and continuous method of stress assessment in unrestrained animals has the potential to become common practice in pure and applied research.
Affiliation: Institute of Biodiversity, Animal Health and Comparative Medicine College of Medical, Veterinary & Life Sciences, University of Glasgow, Glasgow, UK. Electronic address: firstname.lastname@example.org.Show MeSH
Related in: MedlinePlus
Mentions: Skin temperature measurement by IRT requires bare skin . Different regions of the skin vary in whether exhibit temperature changes under acute stress, for example in humans, cooling occurs on the nose but not the cheeks . The naturally bare face, comb and wattle, in addition to the eye, make the chicken an excellent model for comparing amongst potential skin regions in the development of this method. In chickens, gentle ÔÇścradleÔÇÖ handling (Fig. 1A) is stressful: previous work has shown that catecholamine levels rise immediately , and comb and eye temperature drop within a minute by around 2┬á┬░C and 0.8┬á┬░C, respectively , whilst core temperature increases around 0.5┬á┬░C over 9ÔÇô12┬ámin . This is distinct from thermal changes under heat stress, where catecholamine and corticosterone levels also increase  but facial- and core temperature are positively correlated . More physically restrictive forms of handling than cradling elicit a proportionately stronger acute hormonal stress response . We examined behavioural activity level and corticosterone levels in the 20┬ámin following exposure to cradling or a more restrictive hold: side-pinning (Fig. 1A), to demonstrate that these constitute a mild and more stressful handling technique respectively. Accordingly, we measured skin temperature using IRT after applying these handling techniques to test whether skin temperature changes differed between the two levels of acute stressor intensity.
Affiliation: Institute of Biodiversity, Animal Health and Comparative Medicine College of Medical, Veterinary & Life Sciences, University of Glasgow, Glasgow, UK. Electronic address: email@example.com.